阅读说明：本技术 可移动平台的导航方法、设备、计算机可读存储介质 (Navigation method, device and computer readable storage medium for movable platform ) 是由 刘寒颖 李星河 邱凡 于 2019-04-18 设计创作，主要内容包括：一种可移动平台的导航方法、设备、计算机可读存储介质,所述可移动平台上设有多个超声波传感器,该方法包括：获取所述多个超声波传感器的探测数据(S100)；依据所述探测数据生成探测区域描述地图,所述探测区域描述地图与所述多个超声波传感器的探测区域内的场景相关(S200)；依据所述探测区域描述地图确定所述可移动平台在所述场景中的行驶路线(S300)。可解决可移动平台在相机、激光雷达和毫米波雷达等传感器盲区内的导航问题。(A navigation method, equipment and a computer readable storage medium of a movable platform, wherein a plurality of ultrasonic sensors are arranged on the movable platform, and the method comprises the following steps: acquiring detection data of the plurality of ultrasonic sensors (S100); generating a detection area description map from the detection data, the detection area description map relating to a scene within detection areas of the plurality of ultrasonic sensors (S200); determining a driving route of the movable platform in the scene according to the detection area description map (S300). The navigation problem of the movable platform in sensor blind areas such as cameras, laser radars, millimeter wave radars and the like can be solved.)

1. A navigation method of a movable platform is characterized in that a plurality of ultrasonic sensors are arranged on the movable platform, and the method comprises the following steps:

acquiring detection data of the plurality of ultrasonic sensors;

generating a detection area description map according to the detection data, wherein the detection area description map is related to scenes in detection areas of the plurality of ultrasonic sensors;

determining a travel route of the movable platform in the scene from the probe area description map.

2. The method for navigating a movable platform according to claim 1, wherein generating a probe area description map from the probe data comprises:

for each ultrasonic sensor, determining a target distance related to a scene in a detection area of the ultrasonic sensor according to detection data of the ultrasonic sensor;

and generating the detection area description map according to the target distance of each ultrasonic sensor.

3. The method for navigating a movable platform according to claim 2, wherein the probe area description map comprises a status description map;

generating the detection area description map according to the target distance of each ultrasonic sensor, wherein the method comprises the following steps:

constructing a first map to be processed;

determining an unavailable state in a detection area of each ultrasonic sensor in the first map according to the target distance; the non-passable state indicates that the movable platform is not passable;

determining the passable state in each detection area in the first map with the determined non-passable state according to the target distance to obtain a state description map; the passable state indicates that the movable platform is passable.

4. The method for navigating a movable platform according to claim 3, wherein determining the non-passable condition in the detection area of each ultrasonic sensor in the first map based on the target distance comprises:

traversing the target distance of each ultrasonic sensor;

and if the target distance of the traversed ultrasonic sensor is the distance when the obstacle is detected, determining a sub-area corresponding to the target distance in the detection area of the ultrasonic sensor in the first map, and modifying the state of the sub-area in the first map from the identified unknown state to the non-passing state.

5. The method for navigating a movable platform according to claim 3,

the detection areas of the adjacent ultrasonic sensors in the first map have intersection areas;

determining a passable state in each detection area in the first map in which the non-passable state is determined according to the target distance, including:

traversing the target distance of each ultrasonic sensor;

if the target distance of the traversed ultrasonic sensor is the distance when the obstacle is detected, determining a sub-area corresponding to the target distance in the detection area of the ultrasonic sensor in the first map, determining a first local area in the sub-area, wherein the first local area is located in a specified intersection area of the detection area, and determining the passable state of the specified intersection area according to the first local area.

6. The method for navigating a movable platform according to claim 5, wherein determining the passable status of the designated intersection area in dependence of the first local area comprises:

checking whether a target local area with a state of being unable to pass outside the first local area exists in the designated intersection area;

if yes, comparing the distance from the first local area to the first coordinate with the distance from the target local area to the first coordinate, determining a first area Z1 to be adjusted in the designated intersection area by taking the local area with a farther comparison result as a reference position, and adjusting the state of the first area Z1 to be a passable state;

if not, determining a second area Z2 to be adjusted in the designated intersection area by taking the first local area as a reference position, and modifying the state of the second area Z2 from an unknown state to a passable state;

wherein the first coordinates are coordinates of the ultrasonic sensor in a first map.

7. The method for navigating a movable platform according to claim 6, wherein the adjusting the state of the first zone Z1 to a passable state comprises:

the state of the local region closer to the comparison result in the first region Z1 is modified from the non-passable state to the passable state, and the states of the regions other than the local region closer to the comparison result in the first region Z1 are modified from the unknown state to the passable state.

8. The method for navigating a movable platform according to claim 5, wherein after determining the sub-area corresponding to the target distance within the probe area of the corresponding ultrasonic sensor in the first map, further comprising:

determining a second local region in the sub-regions, the second local region being located in a non-intersection region within the detection region;

and determining a third area Z3 to be adjusted in the non-intersection area by taking the second local area as a reference position, and modifying the state of the third area Z3 from an unknown state to a passable state.

9. The method for navigating a movable platform according to claim 5, wherein the passing state in each detection area in the first map in which the non-passing state has been determined is determined according to the target distance, further comprising:

and if the target distance of the traversed ultrasonic sensor is the distance when no obstacle is detected, adjusting the detection area state of the ultrasonic sensor in the first map into a passing state.

10. The method of claim 9, wherein adjusting the detection zone status of the ultrasonic sensor in the first map to a passable status comprises:

checking whether the detection area has a fourth area Z4 identified as a non-passable state;

if so, modifying the state of the fourth zone Z4 in the detection zone from an unobstructable state to a passable state, and modifying the state of the zone outside the fourth zone Z4 in the detection zone from an unknown state to a passable state;

if not, the state of the detection area is modified from an unknown state to a passing state.

11. The method for navigating a movable platform according to claim 4 or 5, wherein determining a sub-area corresponding to the target distance within the detection area of the ultrasonic sensor in the first map comprises:

determining at least one coordinate corresponding to the target distance in a preset corresponding relation between the distance and the coordinate;

and determining the area positioned by all the determined coordinates in the detection area in the first map as the sub-area.

12. The method of navigating a movable platform of claim 2, wherein the probe region description map comprises a distance field description map;

generating the detection area description map according to the target distance of each ultrasonic sensor, wherein the method comprises the following steps:

constructing a second map to be processed;

determining distance information of coordinates in each detection area in the second map according to the target distance of each ultrasonic sensor; wherein the distance information indicates one of a closest distance of the coordinates from the obstacle and a closest distance of the coordinates from a specified boundary of the detection area;

a second map of distance information for which coordinates are determined is taken as the distance field description map.

13. The method for navigating a movable platform according to claim 12, wherein determining distance information of coordinates within each detection area in the second map based on the target distance of each ultrasonic sensor comprises:

traversing the target distance of each ultrasonic sensor;

if the target distance of the traversed ultrasonic sensor is the distance when the obstacle is detected, determining at least one obstacle coordinate corresponding to the target distance in a detection area of the ultrasonic sensor on the second map, and determining a fifth area Z5 needing to determine distance information in the detection area by taking all the obstacle coordinates as reference positions;

for each coordinate in the fifth area Z5, the current distance information of the coordinate is determined according to the historical distance information of the coordinate and the position relationship between the coordinate and all the obstacle coordinates.

14. The method of claim 13, wherein determining the current distance information of the coordinates according to the historical distance information of the coordinates and the position relationship between the coordinates and the coordinates of all obstacles comprises:

if the historical distance information is equal to a first set value representing unknown distance, determining target distance information according to the closest distance between the coordinate and the coordinates of all the obstacles, and determining the target distance information as the current distance information of the coordinate;

if the historical distance information is larger than a first set value and smaller than or equal to a second set value, determining target distance information according to the closest distance between the coordinate and all the coordinates of the obstacle, selecting the optimal distance information S1 from the target distance information and the historical distance information, and determining the optimal distance information S1 as the current distance information of the coordinate;

and if the historical distance information is larger than the second set value, determining the historical distance information as the current distance information of the coordinate.

15. The method of claim 14, wherein determining the target distance information based on the closest distance between the coordinates and all obstacle coordinates comprises:

calculating the distance between the coordinate and the second coordinate; the second coordinates are coordinates of the ultrasonic sensor in a second map;

a first difference between the traversed target distance and the calculated distance; the first difference is the closest distance between the coordinate and the coordinates of all the obstacles;

determining the target distance information according to the first difference, wherein the smaller the first difference is, the smaller the target distance information is;

the optimal distance information S1 is the smaller distance information of the target distance information and the historical distance information.

16. The method for navigating a movable platform according to claim 12, wherein the determining distance information of coordinates within each detection area in the second map based on the target distance of each ultrasonic sensor further comprises:

and if the target distance of the traversed ultrasonic sensor is the distance when no obstacle is detected, determining the current distance information of the coordinate according to the historical distance information of the coordinate and the position relation between the coordinate and the specified boundary of the detection area aiming at each coordinate in the detection area of the ultrasonic sensor of the second map.

17. The method of claim 16, wherein determining the current distance information for the coordinates based on historical distance information for the coordinates and a positional relationship between the coordinates and the specified boundary of the probe region comprises:

if the historical distance information is smaller than or equal to a second set value, determining target distance information according to the closest distance between the coordinate and the specified boundary of the detection area, and determining the target distance information as the current distance information of the coordinate;

if the historical distance information is greater than the second set value, determining target distance information according to the closest distance between the coordinate and the specified boundary of the detection area, selecting optimal distance information S2 from the target distance information and the historical distance information, and determining the optimal distance information S2 as the current distance information of the coordinate.

18. The method for navigating a movable platform of claim 17,

the specified boundary is the boundary of the maximum measuring range of the ultrasonic sensor, wherein the shortest distance between the specified boundary and the second coordinate in the detection area is the maximum measuring range of the ultrasonic sensor; the second coordinates are coordinates of the ultrasonic sensor in a second map;

determining target distance information greater than the second set value according to the closest distance between the coordinate and the specified boundary of the detection area, including:

calculating the distance between the coordinate and the second coordinate;

calculating a second difference between the maximum measuring range and the calculated distance, wherein the second difference is the closest distance between the coordinate and the specified boundary of the detection area;

determining the target distance information according to the second difference, wherein the smaller the second difference is, the smaller the target distance information is, and the target distance information is larger than the second set value;

the optimal distance information S2 is the smaller distance information of the target distance information and the historical distance information.

19. The method for navigating a movable platform according to claim 12, wherein determining the travel route of the movable platform in the scene from the probe area description map comprises:

determining a coordinate with maximum distance information as a target coordinate in the distance field description map;

searching coordinates of distance information of which the distance information is larger than a second set value and smaller than the target coordinates in coordinates around the target coordinates of the distance field description map;

if the distance field description map is found, determining the found coordinates as target coordinates, and returning to the operation of finding the coordinates of the distance information of which the distance information is larger than a second set value and smaller than the target coordinates in the coordinates around the target coordinates of the distance field description map;

and if the mobile platform is not found, determining the driving route of the mobile platform by using the determined target coordinates.

20. The method of claim 2, wherein determining a target distance associated with the scene within the detection zone of the ultrasonic sensor based on the detection data of the ultrasonic sensor comprises:

acquiring M pieces of historical detection data detected by the ultrasonic sensor before the detection data, wherein M is more than or equal to 1;

calculating median values of the probe data and the M historical probe data;

determining a median value as the target distance.

21. The method of claim 2, wherein determining a target distance associated with the scene within the detection zone of the ultrasonic sensor based on the detection data of the ultrasonic sensor comprises:

acquiring M pieces of historical detection data detected by the ultrasonic sensor before the detection data, wherein M is more than or equal to 1;

calculating median values of the probe data and the M historical probe data;

if the median is the distance when the obstacle is detected, performing smooth filtering processing on the median;

and determining the smooth filtering processing result as the target distance.

22. The method of claim 21, wherein the smoothing filter processing the median value comprises:

acquiring N historical median values of the ultrasonic sensor determined before the median value, wherein N is greater than or equal to 1;

calculating the mean value of the median value and N historical median values;

determining a result of the smoothing filter processing as the target distance, including:

determining the mean as the target distance.

23. An electronic device, comprising: a memory and a processor;

the memory for storing program code;

the processor, configured to invoke the program code, when the program code is executed, is configured to perform the following:

acquiring detection data of a plurality of ultrasonic sensors; the ultrasonic sensors are arranged on the movable platform;

generating a detection area description map according to the detection data, wherein the detection area description map is related to scenes in detection areas of the plurality of ultrasonic sensors;

determining a travel route of the movable platform in the scene from the probe area description map.

24. The electronic device of claim 23, wherein the processor, when generating a probe region description map based on the probe data, is specifically configured to:

for each ultrasonic sensor, determining a target distance related to a scene in a detection area of the ultrasonic sensor according to detection data of the ultrasonic sensor;

and generating the detection area description map according to the target distance of each ultrasonic sensor.

25. The electronic device of claim 24, wherein the probe area description map comprises a status description map;

when the processor generates the detection area description map according to the target distance of each ultrasonic sensor, the processor is specifically configured to:

constructing a first map to be processed;

determining an unavailable state in a detection area of each ultrasonic sensor in the first map according to the target distance; the non-passable state indicates that the movable platform is not passable;

determining the passable state in each detection area in the first map with the determined non-passable state according to the target distance to obtain a state description map; the passable state indicates that the movable platform is passable.

26. The electronic device of claim 25, wherein the processor, when determining the non-passable condition within the detection area of each ultrasonic sensor in the first map based on the target distance, is specifically configured to:

traversing the target distance of each ultrasonic sensor;

and if the target distance of the traversed ultrasonic sensor is the distance when the obstacle is detected, determining a sub-area corresponding to the target distance in the detection area of the ultrasonic sensor in the first map, and modifying the state of the sub-area in the first map from the identified unknown state to the non-passing state.

27. The electronic device of claim 25,

the detection areas of the adjacent ultrasonic sensors in the first map have intersection areas;

when the processor determines, according to the target distance, a passable state in each detection area in the first map in which the non-passable state is determined, the processor is specifically configured to:

traversing the target distance of each ultrasonic sensor;

if the target distance of the traversed ultrasonic sensor is the distance when the obstacle is detected, determining a sub-area corresponding to the target distance in the detection area of the ultrasonic sensor in the first map, determining a first local area in the sub-area, wherein the first local area is located in a specified intersection area of the detection area, and determining the passable state of the specified intersection area according to the first local area.

28. The electronic device of claim 27, wherein the processor, when determining the passable state of the designated intersection region in dependence on the first local region, is specifically configured to:

checking whether a target local area with a state of being unable to pass outside the first local area exists in the designated intersection area;

if yes, comparing the distance from the first local area to the first coordinate with the distance from the target local area to the first coordinate, determining a first area Z1 to be adjusted in the designated intersection area by taking the local area with a farther comparison result as a reference position, and adjusting the state of the first area Z1 to be a passable state;

if not, determining a second area Z2 to be adjusted in the designated intersection area by taking the first local area as a reference position, and modifying the state of the second area Z2 from an unknown state to a passable state;

wherein the first coordinates are coordinates of the ultrasonic sensor in a first map.

29. The electronic device of claim 28, wherein the processor, when adjusting the state of the first zone Z1 to the pass state, is specifically configured to:

the state of the local region closer to the comparison result in the first region Z1 is modified from the non-passable state to the passable state, and the states of the regions other than the local region closer to the comparison result in the first region Z1 are modified from the unknown state to the passable state.

30. The electronic device of claim 27, wherein after the processor determines a sub-region of the first map corresponding to the target distance within the detection region of the ultrasonic sensor, the processor is further configured to:

determining a second local region in the sub-regions, the second local region being located in a non-intersection region within the detection region;

and determining a third area Z3 to be adjusted in the non-intersection area by taking the second local area as a reference position, and modifying the state of the third area Z3 from an unknown state to a passable state.

31. The electronic device of claim 27, wherein the processor determines, from the target distance, a passable state within each detection area in the first map for which the non-passable state has been determined, and is further configured to:

and if the target distance of the traversed ultrasonic sensor is the distance when no obstacle is detected, adjusting the detection area state of the ultrasonic sensor in the first map into a passing state.

32. The electronic device of claim 31, wherein the processor is configured to, when adjusting the detection area status of the ultrasonic sensor in the first map to a passable status, in particular:

checking whether the detection area has a fourth area Z4 identified as a non-passable state;

if so, modifying the state of the fourth zone Z4 in the detection zone from an unobstructable state to a passable state, and modifying the state of the zone outside the fourth zone Z4 in the detection zone from an unknown state to a passable state;

if not, the state of the detection area is modified from an unknown state to a passing state.

33. The electronic device according to claim 26 or 27, wherein the processor, when determining a sub-area corresponding to the target distance within the detection area of the ultrasonic sensor in the first map, is specifically configured to:

determining at least one coordinate corresponding to the target distance in a preset corresponding relation between the distance and the coordinate;

and determining the area positioned by all the determined coordinates in the detection area in the first map as the sub-area.

34. The electronic device of claim 24, wherein the probe region description map comprises a distance field description map;

when the processor generates the detection area description map according to the target distance of each ultrasonic sensor, the processor is specifically configured to:

constructing a second map to be processed;

determining distance information of coordinates in each detection area in the second map according to the target distance of each ultrasonic sensor; wherein the distance information indicates one of a closest distance of the coordinates from the obstacle and a closest distance of the coordinates from a specified boundary of the detection area;

a second map of distance information for which coordinates are determined is taken as the distance field description map.

35. The electronic device of claim 34, wherein the processor, when determining distance information for coordinates within each detection area in the second map based on the target distance of each ultrasonic sensor, is specifically configured to:

traversing the target distance of each ultrasonic sensor;

if the target distance of the traversed ultrasonic sensor is the distance when the obstacle is detected, determining at least one obstacle coordinate corresponding to the target distance in a detection area of the ultrasonic sensor on the second map, and determining a fifth area Z5 needing to determine distance information in the detection area by taking all the obstacle coordinates as reference positions;

for each coordinate in the fifth area Z5, the current distance information of the coordinate is determined according to the historical distance information of the coordinate and the position relationship between the coordinate and all the obstacle coordinates.

36. The electronic device of claim 35, wherein the processor, when determining the current distance information of the coordinate according to the historical distance information of the coordinate and the position relationship between the coordinate and all obstacle coordinates, is specifically configured to:

if the historical distance information is equal to a first set value representing unknown distance, determining target distance information according to the closest distance between the coordinate and the coordinates of all the obstacles, and determining the target distance information as the current distance information of the coordinate;

if the historical distance information is larger than a first set value and smaller than or equal to a second set value, determining target distance information according to the closest distance between the coordinate and all the coordinates of the obstacle, selecting the optimal distance information S1 from the target distance information and the historical distance information, and determining the optimal distance information S1 as the current distance information of the coordinate;

and if the historical distance information is larger than the second set value, determining the historical distance information as the current distance information of the coordinate.

37. The electronic device of claim 36, wherein the processor, when determining the target distance information based on the closest distance between the coordinate and all of the obstacle coordinates, is further configured to:

calculating the distance between the coordinate and the second coordinate; the second coordinates are coordinates of the ultrasonic sensor in a second map;

a first difference between the traversed target distance and the calculated distance; the first difference is the closest distance between the coordinate and the coordinates of all the obstacles;

determining the target distance information according to the first difference, wherein the smaller the first difference is, the smaller the target distance information is;

the optimal distance information S1 is the smaller distance information of the target distance information and the historical distance information.

38. The electronic device of claim 34, wherein the processor, when determining distance information for coordinates within each detection area in the second map based on the target distance of each ultrasonic sensor, is further configured to:

and if the target distance of the traversed ultrasonic sensor is the distance when no obstacle is detected, determining the current distance information of the coordinate according to the historical distance information of the coordinate and the position relation between the coordinate and the specified boundary of the detection area aiming at each coordinate in the detection area of the ultrasonic sensor of the second map.

39. The electronic device of claim 38,

when the processor determines the current distance information of the coordinate according to the historical distance information of the coordinate and the position relationship between the coordinate and the specified boundary of the detection area, the processor is specifically configured to:

if the historical distance information is smaller than or equal to the second set value, determining target distance information according to the closest distance between the coordinate and the specified boundary of the detection area, and determining the target distance information as the current distance information of the coordinate;

if the historical distance information is greater than the second set value, determining target distance information according to the closest distance between the coordinate and the specified boundary of the detection area, selecting optimal distance information S2 from the target distance information and the historical distance information, and determining the optimal distance information S2 as the current distance information of the coordinate.

40. The electronic device of claim 39, wherein the specified boundary is a boundary in the probe region having a closest distance to the second coordinate that is a maximum range of the ultrasonic sensor; the second coordinates are coordinates of the ultrasonic sensor in a second map;

when the processor determines the target distance information greater than the second set value according to the closest distance between the coordinate and the specified boundary of the detection area, the processor is specifically configured to:

calculating the distance between the coordinate and the second coordinate;

calculating a second difference between the maximum measuring range and the calculated distance, wherein the second difference is the closest distance between the coordinate and the specified boundary of the detection area;

determining the target distance information according to the second difference, wherein the smaller the second difference is, the smaller the target distance information is, and the target distance information is larger than the second set value;

the optimal distance information S2 is the smaller distance information of the target distance information and the historical distance information.

41. The electronic device of claim 34, wherein the processor, when determining the travel route of the movable platform in the scene from the probe area description map, is specifically configured to:

determining a coordinate with maximum distance information as a target coordinate in the distance field description map;

searching coordinates of distance information of which the distance information is larger than a second set value and smaller than the target coordinates in coordinates around the target coordinates of the distance field description map;

if the distance field description map is found, determining the found coordinates as target coordinates, and returning to the operation of finding the coordinates of the distance information of which the distance information is larger than a second set value and smaller than the target coordinates in the coordinates around the target coordinates of the distance field description map;

and if the mobile platform is not found, determining the driving route of the mobile platform by using the determined target coordinates.

42. The electronic device of claim 24, wherein the processor, when determining the target distance associated with the scene within the detection area of the ultrasonic sensor based on the detection data of the ultrasonic sensor, is specifically configured to:

acquiring M pieces of historical detection data detected by the ultrasonic sensor before the detection data, wherein M is more than or equal to 1;

calculating median values of the probe data and the M historical probe data;

determining a median value as the target distance.

43. The electronic device of claim 24, wherein the processor, in determining the target distance associated with the scene within the detection area of the ultrasonic sensor based on the detection data of the ultrasonic sensor, is specifically configured to:

acquiring M pieces of historical detection data detected by the ultrasonic sensor before the detection data, wherein M is more than or equal to 1;

calculating median values of the probe data and the M historical probe data;

if the median is the distance when the obstacle is detected, performing smooth filtering processing on the median;

and determining the smooth filtering processing result as the target distance.

44. The electronic device of claim 43, wherein the processor, when performing the smoothing filtering on the median value, is specifically configured to:

acquiring N historical median values of the ultrasonic sensor determined before the median value, wherein N is greater than or equal to 1;

calculating the mean value of the median value and N historical median values;

determining a result of the smoothing filter processing as the target distance, including:

determining the mean as the target distance.

45. A computer-readable storage medium, characterized in that,

the computer-readable storage medium having stored thereon computer instructions which, when executed, implement the method of navigation of a movable platform of any of claims 1-22.

Technical Field

The present disclosure relates to the field of navigation technologies, and in particular, to a navigation method, a navigation device, and a computer-readable storage medium for a mobile platform.

Background

Maps are an indispensable part of a mobile platform to enable navigation. The movable platform comprises an unmanned aerial vehicle, a robot and the like, and can realize path planning by using a map and further move according to the planned path to avoid obstacles. Taking an unmanned aerial vehicle as an example, in the flight process, obstacles may exist in the environment, particularly in the indoor flight environment, various obstacles such as walls, devices and the like may exist, and thus a map describing the environment needs to be formed to perform path planning so as to realize obstacle avoidance in flight.

Sensors such as cameras, lidar and millimeter wave radar play an important role in navigation. However, because the installation position and the characteristics of the sensors are limited, a detection blind area with a large range exists, and the detection performance in a range close to the movable platform cannot be guaranteed, so that the technical problem of how to realize the navigation of the movable platform in the sensor blind area still needs to be solved.

Disclosure of Invention

The specification provides a navigation method, a navigation device and a computer readable storage medium for a movable platform, which can solve the problem of navigation of the movable platform in dead zones of sensors such as a camera, a laser radar and a millimeter wave radar.

In a first aspect of the embodiments of the present specification, there is provided a navigation method for a movable platform, where the movable platform is provided with a plurality of ultrasonic sensors, the method including:

acquiring detection data of the plurality of ultrasonic sensors;

generating a detection area description map according to the detection data, wherein the detection area description map is related to scenes in detection areas of the plurality of ultrasonic sensors;

determining a travel route of the movable platform in the scene from the probe area description map.

In a second aspect of embodiments herein, an electronic device includes: a memory and a processor;

the memory for storing program code;

the processor, configured to invoke the program code, when the program code is executed, is configured to perform the following:

acquiring detection data of a plurality of ultrasonic sensors; the ultrasonic sensors are arranged on the movable platform;

generating a detection area description map according to the detection data, wherein the detection area description map is related to scenes in detection areas of the plurality of ultrasonic sensors;

determining a travel route of the movable platform in the scene from the probe area description map.

In a third aspect of the embodiments of the present specification, a computer-readable storage medium is provided, on which computer instructions are stored, and when the computer instructions are executed, the method for navigating a movable platform according to the first aspect of the embodiments of the present specification is implemented.

Based on the above technical solution, in the navigation method of the movable platform in the embodiments of the present specification, a plurality of ultrasonic sensors are used to detect a situation in a scene where the movable platform is located, a detection area description map is determined according to detection data of each ultrasonic sensor, and since the detection area description map is related to a scene in detection areas of the plurality of ultrasonic sensors, it is described that the detection area description map can determine an obstacle situation in the scene, so that a driving route of the movable platform in the scene is determined according to the detection area description map, navigation of the movable platform is realized, an obstacle can be avoided in time during driving, since the ultrasonic sensors can detect in a range less than 0.3m, compared with the sensors such as a camera, a laser radar, and a millimeter wave radar, etc., a shorter-distance detection can be realized, and the movable platform can be navigated in a detection blind area of the sensors, making up for the deficiencies of these sensors.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present specification, the drawings needed to be used in the embodiments of the present specification will be briefly described below, it is obvious that the drawings in the following description are only some embodiments described in the present specification, and it is obvious for a person skilled in the art that other drawings can be obtained according to the drawings of the embodiments of the present specification.

FIG. 1 is a flow diagram illustrating a method for navigating a movable platform according to one embodiment of the disclosure;

FIG. 2 is a schematic diagram of a detection zone of an ultrasonic sensor according to one embodiment of the present disclosure;

FIG. 3 is a schematic illustration of three detection zones for which a no-pass condition has been determined in one embodiment of the present description;

FIG. 4 is a schematic diagram of a distance field description map according to an embodiment of the specification;

fig. 5 is a block diagram of an electronic device according to an embodiment of the present specification.

Detailed Description

The technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the drawings in the embodiments of the present disclosure, and it is obvious that the described embodiments are only a part of the embodiments of the present disclosure, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments in the present specification without any creative effort belong to the protection scope of the present specification. In addition, the features in the embodiments and the examples described below may be combined with each other without conflict.

The terminology used in the description herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the description. As used in this specification and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should be understood that the term "and/or" as used herein is meant to encompass any and all possible combinations of one or more of the associated listed items.

Although the terms first, second, third, etc. may be used herein to describe various information, the information should not be limited to these terms. These terms are used to distinguish one type of information from another. For example, the first information may also be referred to as second information, and similarly, the second information may also be referred to as first information, without departing from the scope of the present specification. Depending on the context, moreover, the word "if" is used may be interpreted as "at … …," or "when … …," or "in response to a determination.

The following describes the navigation method of the movable platform in more detail, but should not be limited thereto.

A method for navigating a movable platform provided with a plurality of ultrasonic sensors, see fig. 1, comprising the steps of:

s100: acquiring detection data of the plurality of ultrasonic sensors;

s200: generating a detection area description map according to the detection data, wherein the detection area description map is related to scenes in detection areas of the plurality of ultrasonic sensors;

s300: determining a travel route of the movable platform in the scene from the probe area description map.

An execution subject of the navigation method of the movable platform of the embodiments of the present specification may be an electronic device, and more specifically, may be a processor of the electronic device. The electronic device may be, for example, a movable platform or a device mounted on and communicatively coupled to a movable platform via a wired or wireless connection.

The movable platform can be an unmanned aerial vehicle, a robot and the like, and the map obtained by the navigation method of the movable platform in the embodiment of the specification can realize autonomous navigation functions such as path planning and the like.

A plurality of ultrasonic sensors (alternatively referred to as ultrasonic probes) are disposed on the movable platform. The number of the ultrasonic sensors disposed on the movable platform may be 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 or more, and the specific number of the ultrasonic sensors is not limited in the embodiments of the present specification. As an alternative embodiment, the ultrasonic sensors are present in pairs, symmetrically mounted to the movable platform.

For example, each ultrasonic sensor may be disposed around the movable platform with its transmitting probe facing the outside of the movable platform. The detection range of all the ultrasonic sensors may cover all or part of the periphery of the movable platform, and the part of the periphery includes the front, the left side, the right side, the upper side, the lower side and the like of the movable platform.

Each ultrasonic sensor is also electrically connected with the electronic equipment, can process the received reflection echo to obtain detection data, and transmits the detection data to the electronic equipment.

Taking the movable platform as an example of a vehicle, a plurality of ultrasonic sensors are arranged on the vehicle and used for transmitting ultrasonic waves to a specified direction and detecting the condition around the vehicle according to reflected echoes. In the plurality of ultrasonic sensors, the detection ranges of two adjacent ultrasonic sensors may or may not partially overlap, and may specifically depend on the relative position relationship of the ultrasonic sensors.

The plurality of ultrasonic sensors may emit ultrasonic waves for detection simultaneously or sequentially, and determine corresponding detection data according to the reflected echoes, and generally, if the ultrasonic sensors receive the reflected echoes, it is indicated that an obstacle has been detected in the effective range of the ultrasonic sensors, the detection data calculated according to the flight time of the ultrasonic waves may be regarded as the detected distance of the surrounding object, and if the ultrasonic sensors do not receive the echoes, it is indicated that an obstacle has not been detected in the effective range of the ultrasonic sensors, and the detection data is the distance at which an obstacle has not been detected (may be represented by a value exceeding the effective range, and may also be represented by other data).

In step S100, probe data of the plurality of ultrasonic sensors is acquired.

The detection data can be the result of synchronous detection of a plurality of ultrasonic sensors during the movement of the movable platform. When the movable platform moves to a certain position, the detection data of the ultrasonic sensors can represent the obstacle condition around the movable platform when the movable platform is at the position.

In step S200, a detection area description map is generated according to the detection data, and the detection area description map is related to the scenes in the detection areas of the plurality of ultrasonic sensors.

For the acquired detection data of each ultrasonic sensor, if the detection data is the distance when no obstacle is detected, it is indicated that no obstacle exists in the detection range of the ultrasonic sensor, if the detection data is the distance when an obstacle is detected, it is indicated that an obstacle exists in the detection range of the ultrasonic sensor, and the detection data is the distance between the obstacle and the ultrasonic sensor.

In other words, the detection data may account for conditions in the scene within the detection area of the ultrasonic sensor, such as the presence or absence of an obstacle, the distance of the obstacle, and so forth. Thus, a detection area description map required for the travel route of the movable platform can be determined from the detection data, the detection area description map relating to the scene within the detection areas of the plurality of ultrasonic sensors, so that the movable platform can avoid obstacles in the scene while traveling.

The shape of the detection regions of the ultrasonic sensors may be as shown in fig. 2, and the overlapping of the detection regions of a plurality of ultrasonic sensors may be as shown in fig. 3, which will be described in the following embodiments.

For example, the detection zone description map may be used to describe which locations in the scene within the detection zone of the ultrasonic sensor are passable by the movable platform and which locations are not passable by the movable platform. Illustratively, as shown in FIG. 3, X2 is impassable by a movable platform, while the area between X2 and U2 is traversable by a movable platform.

For another example, the detection area description map may be used to describe distances between various positions in the scene in the detection area of the ultrasonic sensor and obstacles (in the case of an obstacle in the detection area), and if a certain position is close to the obstacle, the position is not suitable for the movable platform to pass through, and if the certain position is far from the obstacle, the position is suitable for the movable platform to pass through. For example, as shown in fig. 4, the detection area description map is divided into grids, values in the grids describe the distance between the grids and the obstacle, the larger the value is, the farther the grid is from the obstacle is, and when the value is less than or equal to a certain value, the grid is too close to the obstacle and is not suitable for the movable platform to pass through.

In step S300, a driving route of the movable platform in the scene is determined according to the detection area description map.

After the detection area description map is obtained, the condition of the obstacles in the scene can be determined according to the detection area description map, accordingly, a driving route required by driving in the scene can be determined for the movable platform, and the determined driving route can be an optimal route or more than two optional routes. The movable platform may travel according to the determined travel route.

If the probe area description map describes which locations in the scene are passable by the movable platform and which locations are not passable by the movable platform, the passable locations may be used to form a driving route.

In an alternative embodiment, the optimal path of the movable platform may be determined using a survey area description map. The detection area description map is used for describing the distance between each position in a scene in the detection area of the ultrasonic sensor and the obstacle, and the optimal path can be determined through the gradient change condition of the distance between the optimal path and the obstacle, which is described in the detection area state diagram. Referring to fig. 4, starting from the grid of 255 above U1, the next grid where the value having the smallest difference with 255 and having the difference larger than the specified value is located is found, such as the grid of 254 above the grid of 255 in the figure, and so on, the subsequent grids are found, and the found grids are used to form the optimal route.

In the embodiment of the specification, a plurality of ultrasonic sensors are adopted to detect the condition in the scene of the movable platform, a detection area description map is determined according to the detection data of each ultrasonic sensor, since the detection area description map is related to the scene in the detection areas of the plurality of ultrasonic sensors, it is explained that the detection area description map can determine the condition of the obstacles in the scene, therefore, the driving route of the movable platform in the scene is determined according to the detection area description map, the navigation of the movable platform is realized, the obstacle can be avoided in time during the driving process, because the ultrasonic sensor can detect within the range of less than 0.3m, the ultrasonic sensor can realize the detection at a shorter distance compared with the sensors such as a camera, a laser radar, a millimeter wave radar and the like, navigation is carried out on the movable platform in the detection blind areas of the sensors, and the defects of the sensors are overcome.

In one embodiment, in step S200, generating a probe area description map according to the probe data includes the following steps:

for each ultrasonic sensor, determining a target distance related to a scene in a detection area of the ultrasonic sensor according to detection data of the ultrasonic sensor;

and generating the detection area description map according to the target distance of each ultrasonic sensor.

Due to the fact that the ultrasonic sensor has flickering characteristics in the using process, abnormal detection data can occur, the abnormal detection data are not suitable for determining the state of the detection area, otherwise, the state of the detection area is wrong or has large deviation, and navigation problems can occur.

Thus, for each ultrasonic sensor, the probe data is processed to obtain a target distance associated with the scene within the probe region of that ultrasonic sensor. And generating a detection area description map according to the target distance of each ultrasonic sensor. Since the target distance is more suitable for determining the state of the detection region than the detection data, the problem of detection region state error or large deviation caused by abnormal detection data can be reduced.

The detection data of the ultrasonic sensor is a one-dimensional distance value, and two-dimensional or even three-dimensional data is usually needed to describe the distribution of the obstacles in the space clearly, so that the distribution of the obstacles in the space cannot be described clearly by only depending on the target distance. In fact, although the ultrasonic sensor detects a one-dimensional distance value, the actual detection range of the ultrasonic sensor is planar, and the specification establishes a detection area model of the ultrasonic sensor in a two-dimensional plane for more clearly describing the distribution situation of the obstacles in the space.

In an alternative embodiment, a two-dimensional plane as shown in FIG. 2 is created as a model of the probe region of the ultrasonic sensor. The detection area of the ultrasonic sensor has a shape which is narrow at the top and wide at the bottom, and is similar to a pear shape. The detection area model is used for describing the detection range of the ultrasonic sensor and describing the detection area of the map in the detection area. In fig. 2, the COB is a sector area with O as the center, the ultrasonic sensor U is approximately simplified into a point, the detection area of the U is defined as an area sequentially enclosed by line segments BA, AU, UD, DC and an arc line segment CB, the shape of the area is similar to a pear shape and is a part of the COB, and the maximum range of the U is the nearest distance from the U to the CB.

In one embodiment, the probe area description map includes a status description map.

The method for generating the detection area description map according to the target distance of each ultrasonic sensor comprises the following steps:

s210: constructing a first map to be processed;

s220: determining an unavailable state in a detection area of each ultrasonic sensor in the first map according to the target distance; the non-passable state indicates that the movable platform is not passable;

s230: determining the passable state in each detection area in the first map with the determined non-passable state according to the target distance to obtain a state description map; the passable state indicates that the movable platform is passable.

In step S210, the first map may be a map in which the states of all coordinates are unknown, and the detection area of each ultrasonic sensor is already planned in the first map. The shape and size of each detection region may be the same, and as long as the coordinates and detection direction of the ultrasonic sensor are determined in the first map, the detection region of the ultrasonic sensor may be determined therein, and the shape of the detection region may be as shown in fig. 2. The coordinates and probing direction of the ultrasonic sensor can be determined according to the installation position and orientation of the ultrasonic sensor on the movable platform.

The obstacle situation around the movable platform can be determined according to the target distance, and therefore the passing state and the non-passing state in each detection area in the first map can be determined according to the target distance. The non-passing state indicates that the movable platform is occupied by an obstacle and cannot pass through the corresponding area. The passing state indicates that the movable platform is not occupied by the obstacle and can pass through the corresponding area.

In some cases, there may be a partial overlap of the detection ranges of the ultrasonic sensors, and thus there may be an intersection area between the detection areas in the first map, respectively. If the passing state and the failing state in one detection region are determined first, then the passing state and the failing state in the next detection region are determined, and so on, to determine the states in all the detection regions, an error state may exist in the intersection region, for example, two regions whose states are the failing state exist in the intersection region, and a region whose state is the passing state is sandwiched between the two regions.

In this embodiment, the non-passable states of the detection regions in the first map are determined, and after all the non-passable states are determined, the passable states of the detection regions in the first map are determined, and the first map after the passable states are determined is used as the state description map. Since, when the passable state is determined, the region which is erroneously marked as the non-passable state in the intersection region can be found and corrected, the erroneous state in each intersection region of the first map is avoided.

Of course, in the case where there is no overlap in the detection ranges of the ultrasonic sensors, after the non-passable state and the passable state of one detection region are determined, the non-passable state and the passable state of the next detection region may be determined.

In one embodiment, the step S220 of determining the non-passable state in the detection area of each ultrasonic sensor in the first map according to the target distance includes the following steps:

s221: traversing the target distance of each ultrasonic sensor;

s222: and if the target distance of the traversed ultrasonic sensor is the distance when the obstacle is detected, determining a sub-area corresponding to the target distance in the detection area of the ultrasonic sensor in the first map, and modifying the state of the sub-area in the first map from the identified unknown state to the non-passing state.

In step S221, the traversal may be performed according to a position order of the ultrasonic sensors on the movable platform, such as a clockwise order or a counterclockwise order. For example, if the target distance of a certain ultrasonic sensor is the first traversed target distance, the next traversed target distance is the target distance of the ultrasonic sensor adjacent to the ultrasonic sensor which is not traversed.

Every time an object distance is traversed, whether the traversed object distance is the distance when the obstacle is detected can be checked. The detection can be carried out by judging whether the target distance exceeds the maximum range of the ultrasonic sensor, if the target distance exceeds the maximum range, the condition that distance observation does not exist is indicated, the target distance is the distance when the obstacle is not detected, otherwise, the condition that distance observation exists is indicated, and the target distance is the distance when the obstacle is detected. For example, if the traversed target distance is 2m and the maximum range is 5m, the target distance is the distance when the obstacle is detected.

In step S222, if the traversed target distance is the distance when the obstacle is detected, it indicates that the obstacle exists in the detection range of the ultrasonic sensor, and the closest distance between the obstacle and the ultrasonic sensor is the target distance.

At this time, a sub-area corresponding to the target distance in the detection area of the ultrasonic sensor in the first map may be determined, the sub-area is an area where the obstacle is located, and the state of the sub-area in the first map is modified from the identified unknown state to the non-passable state.

For example, the sub-region may be an arc region centered around O within the "pear-shaped" detection region as shown in fig. 2, and the closest distance between the arc on the arc region closest to the coordinates of the ultrasonic sensor and the coordinates of the ultrasonic sensor is the target distance. The sub-region may be specifically a region composed of X1, X2, and X3 in fig. 3.

The corresponding relation between each distance and the sub-region can be pre-established according to the detection region model, and after the target distance is determined, the sub-region corresponding to the target distance can be determined in the corresponding relation.

In one embodiment, there is an intersection region of the detection regions of adjacent ultrasonic sensors in the first map.

In steps S221 and S222, when the non-passable state is determined, the situation that an error state may exist in the intersection region is not considered, and after the non-passable state is determined, the following situations may exist as shown in fig. 3: in the intersection region, there are both the region X3 in which one state is the non-passing state and the region X4 in which the other state is the non-passing state, and thus there are two regions in the intersection region in which the states are the non-passing state, which needs to be corrected. In the embodiment of the present specification, when the passable state is determined, the error state in that case may be corrected together.

In step S230, the determining, according to the target distance, a passable state in each detection area in the first map in which the non-passable state is determined includes the following steps:

s231: traversing the target distance of each ultrasonic sensor;

s232: if the target distance of the traversed ultrasonic sensor is the distance when the obstacle is detected, determining a sub-area corresponding to the target distance in the detection area of the ultrasonic sensor in the first map, determining a first local area in the sub-area, wherein the first local area is located in a specified intersection area of the detection area, and determining the passable state of the specified intersection area according to the first local area.

The traversal manner of the target distance in step S231 may be the same as or similar to that in step S221, and is not described herein again. Every time an object distance is traversed, whether the traversed object distance is the distance when the obstacle is detected can be checked.

In step S232, if the traversed target distance of the ultrasonic sensor is the distance when the obstacle is detected, a sub-area corresponding to the target distance in the detection area of the ultrasonic sensor in the first map is determined, and the passable state of the designated intersection area is determined according to the first local area. The sub-region is determined in the same or similar manner as in the aforementioned step S222.

In this embodiment, a first local region in the sub-region is determined, the first local region being located within a designated intersection region of the probe region. As shown in fig. 3, a sub-region is composed of X1, X2, and X3, X1 is located at the intersection between the detection regions of U1 and U2, X2 is located at the non-intersection, X3 is located at the intersection between the detection regions of U2 and U3 (for the detection region of U2, the intersection is the designated intersection described in the present embodiment), and X3 is the first local region of the sub-region and is located in the designated intersection with X4.

In one embodiment, the step S232 of determining the passable status of the designated intersection region according to the first local region includes the following steps:

s2321: checking whether a target local area with a state of being unable to pass outside the first local area exists in the designated intersection area;

s2322: if yes, comparing the distance from the first local area to the first coordinate with the distance from the target local area to the first coordinate, determining a first area Z1 to be adjusted in the designated intersection area by taking the local area with a farther comparison result as a reference position, and adjusting the state of the first area Z1 to be a passable state.

S2323: if not, determining a second area Z2 to be adjusted in the designated intersection area by taking the first local area as a reference position, and modifying the state of the second area Z2 from an unknown state to a passable state;

wherein the first coordinates are coordinates of the ultrasonic sensor in a first map.

In step S2321, it is checked whether there are other regions in the designated intersection region whose states are not passable states, except that the state of the first local region is a non-passable state, and if so, the region is the target local region. The target local region and the first local region may have no intersection or a partial intersection as long as the two are not regions on the same arc region.

As shown in fig. 3, with respect to the detection region of the ultrasonic sensor U2, the intersection region between the detection region of the ultrasonic sensor U2 and the detection region of the ultrasonic sensor U3 is a designated intersection region, and a state in which two regions of X3 and X4 exist in the intersection region is designated as a non-passing state, where X3 is a first local region and X4 is a target local region. At this time, the status of the designated intersection region needs to be corrected, and the status of only one region is guaranteed to be the status of the non-passable region.

In step S2322, in the case where the target local area exists in the designated intersection area, which of the first local area and the target local area is farther from the first coordinate of the ultrasonic sensor in the first map is compared, the first area Z1 to be adjusted in the designated intersection area is determined with the farther local area as a reference position, and the state of the first area Z1 is adjusted to the passable state. The first region Z1 is a region on one side of the specified intersection region located at the farther local region near the first coordinate.

In the comparison of the distances, the distance between the coordinates of the designated point on the first local area and the first coordinates and the distance between the coordinates of the designated point on the target local area and the first coordinates may be compared, and the designated point may be, for example, an intersection of the first local area and the same boundary between the target local area and the designated intersection area.

As shown in fig. 3, the distance from X3 to the first coordinate of U2 is shorter than the distance from X4 to the first coordinate, and thus, a first region Z1 is determined with X4 as a reference position, and Z1 is a region on one side of the designated intersection region which is located near the first coordinate of X4.

In step S2323, when the target local region does not exist in the designated intersection region, it is described that the state of only one region, i.e., the first local region, in the designated intersection region is the non-passable state, and in this case, the non-passable state in the designated intersection region is not corrected.

And determining a second area Z2 to be adjusted in the designated intersection area by taking the first local area as a reference position, and modifying the state of the second area Z2 from an unknown state to a passable state. The second region Z2 is a region on the side of the designated intersection region that is located near the first coordinate in the first local region.

In step S2322, since the first region Z1 includes a region in an unknown state and a region in an inaccessible state, both of these states need to be adjusted to an accessible state. In one embodiment, in step S2322, the adjusting the state of the first zone Z1 to the passable state includes:

the state of the local region closer to the comparison result in the first region Z1 is modified from the non-passable state to the passable state, and the states of the regions other than the local region closer to the comparison result in the first region Z1 are modified from the unknown state to the passable state.

In one embodiment, after determining the sub-area corresponding to the target distance in the detection area of the corresponding ultrasonic sensor in the first map in step S232, the method further includes the following steps:

s2324: determining a second local region in the sub-regions, the second local region being located in a non-intersection region within the detection region;

s2325: and determining a third area Z3 to be adjusted in the non-intersection area by taking the second local area as a reference position, and modifying the state of the third area Z3 from an unknown state to a passable state.

The second partial region is a region of the sub-regions located at a non-intersection region, and the third region Z3 may be a region of the non-intersection region located on a side of the second partial region close to the first coordinate. The state in the third region Z3 is not modified and remains as an unknown state, and thus the state of the third region Z3 is modified from an unknown state to a passable state.

In one embodiment, in step S230, determining a passable state in each detection area in the first map in which the non-passable state is determined according to the target distance further includes:

s233: and if the target distance of the traversed ultrasonic sensor is the distance when no obstacle is detected, adjusting the detection area state of the ultrasonic sensor in the first map into a passing state.

If the target distance of the traversed ultrasonic sensor is the distance when no obstacle is detected, it indicates that no obstacle exists in the detection area of the ultrasonic sensor, and the states in the detection area should all be the passing states, so that the detection area state of the ultrasonic sensor in the first map is adjusted to be the passing state.

Since the state in the intersection region of the detection region of the ultrasonic sensor may have been modified, an impassable state and an unknown state may exist in the intersection region; the non-intersection region of the detection region of the ultrasonic sensor is not modified, and only an unknown state exists.

In one embodiment, the step S233 of adjusting the detection area state of the ultrasonic sensor in the first map to a passable state includes:

s2331: checking whether the detection area has a fourth area Z4 identified as a non-passable state;

s2332: if so, modifying the state of the fourth zone Z4 in the detection zone from an unobstructable state to a passable state, and modifying the state of the zone outside the fourth zone Z4 in the detection zone from an unknown state to a passable state;

s2333: if not, the state of the detection area is modified from an unknown state to a passing state.

It is possible to check whether the detection area has the fourth area Z4 according to the processing result when the non-passable state is determined. The state of the region other than the fourth region Z4 in the detection region is modified from the unknown state to the passable state.

In this embodiment, the coordinates in the detection region may also be traversed, if the state of the traversed coordinates is an unknown state, the unknown state is modified into a passable state, and if the state of the traversed coordinates is an impassable state, the impassable state is modified into a passable state.

In one embodiment, determining a sub-region of the first map corresponding to the target distance within the detection region of the ultrasonic sensor comprises:

determining at least one coordinate corresponding to the target distance in a preset corresponding relation between the distance and the coordinate;

and determining the area positioned by all the determined coordinates in the detection area in the first map as the sub-area.

In the detection region model of the ultrasonic sensor shown in fig. 2, with U as the starting point, an arc line with O as the center can be determined by one distance, so that the preset corresponding relationship between each distance and all coordinates on the corresponding arc line can be established in advance. When determining the sub-region, all coordinates corresponding to the target distance may be determined from the preset correspondence, and all coordinates may form a corresponding arc.

In this embodiment, an arc determined by all coordinates may be expanded in the width direction to form a sub-region with a width, and the width of the sub-region is, for example, 0.02m, and is not limited specifically. The preset corresponding relation can be presented in a form of a table, and all coordinates corresponding to the target distance can be searched in the table.

After obtaining the state description map, the driving route of the movable platform may be determined according to the state description map, for example, the driving route may be determined from an area in the state description map where the state is the passable state.

In one embodiment, the probe region description map includes a distance field description map;

the method for generating the detection area description map according to the target distance of each ultrasonic sensor comprises the following steps:

s240: constructing a second map to be processed;

s250: determining distance information of coordinates in each detection area in the second map according to the target distance of each ultrasonic sensor; wherein the distance information indicates one of a closest distance of the coordinates from the obstacle and a closest distance of the coordinates from a specified boundary of the detection area;

s260: a second map of distance information for which coordinates are determined is taken as the distance field description map.

In step S240, the second map may be a map in which distance information of all coordinates is a first set value, the first set value indicates an unknown distance, and the detection area of each ultrasonic sensor has been determined in the second map. The shape and size of each detection region may be the same, and as long as the coordinates and detection direction of the ultrasonic sensor are determined in the second map, the detection region of the ultrasonic sensor may be determined therein, and the shape of the detection region may be as shown in fig. 2. The coordinates and probing direction of the ultrasonic sensor can be determined according to the installation position and orientation of the ultrasonic sensor on the movable platform.

In step S250, the distance information indicates the smaller of the closest distance of the coordinates from the obstacle and the closest distance of the coordinates from the specified boundary of the detection area. It is understood that the distance information is necessarily the closest distance of the coordinates from the obstacle when the obstacle exists in front of the coordinates of the detection area, and is necessarily the closest distance of the coordinates from the specified boundary if the obstacle does not exist in front of the coordinates of the detection area.

For example, if the target distance is a distance when an obstacle is detected, the target distance is a distance between the obstacle in the detection area and the ultrasonic sensor, and a position or an area of the obstacle can be determined according to the target distance, so that a distance between each coordinate in the detection area and the obstacle can be determined, that is, distance information of each coordinate, which is less than or equal to a second set value, indicating a closest distance of the coordinate to the obstacle can be determined. If the target distance is a distance at which no obstacle is detected, it may be determined that no obstacle is present in the detection area, and distance information of each coordinate, which indicates a closest distance of the coordinate to a specified boundary of the detection area, may be determined to be greater than the second set value. A boundary such as CB as shown in fig. 2 is specified.

In step S260, after the second map is processed, the obtained map is used as the distance field description map.

In one embodiment, the step S250 of determining distance information of coordinates in each detection area in the second map according to the target distance of each ultrasonic sensor includes:

s251: traversing the target distance of each ultrasonic sensor;

s252: if the target distance of the traversed ultrasonic sensor is the distance when the obstacle is detected, determining at least one obstacle coordinate corresponding to the target distance in a detection area of the ultrasonic sensor on the second map, and determining a fifth area Z5 needing to determine distance information in the detection area by taking all the obstacle coordinates as reference positions;

s253: for each coordinate in the fifth area Z5, the current distance information of the coordinate is determined according to the historical distance information of the coordinate and the position relationship between the coordinate and all the obstacle coordinates.

In step S251, the traversal may be performed according to a position order of the ultrasonic sensors on the movable platform, such as a clockwise order or a counterclockwise order. For example, if the target distance of a certain ultrasonic sensor is the first traversed target distance, the next traversed target distance is the target distance of the ultrasonic sensor adjacent to the ultrasonic sensor which is not traversed. The embodiments of the present specification do not limit the specific traversal manner.

In step S252, each time an object distance is traversed, it may be checked whether the traversed object distance is a distance at which an obstacle is detected. The detection can be carried out by judging whether the target distance exceeds the maximum range of the ultrasonic sensor, if the target distance exceeds the maximum range, the condition that distance observation does not exist is indicated, the target distance is the distance when the obstacle is not detected, otherwise, the condition that distance observation exists is indicated, and the target distance is the distance when the obstacle is detected. For example, if the traversed target distance is 2m and the maximum range is 5m, the target distance is the distance when the obstacle is detected.

If the target distance of the traversed ultrasonic sensor is the distance when the obstacle is detected, it is indicated that the obstacle exists in the detection range of the ultrasonic sensor, and the distance between the obstacle and the ultrasonic sensor is the target distance.

At least one obstacle coordinate corresponding to the target distance is determined in the detection area of the ultrasonic sensor of the second map. In the detection region model of the ultrasonic sensor shown in fig. 2, with U as the starting point, an arc line with O as the center can be determined by one distance, so that the preset corresponding relationship between each distance and all coordinates on the corresponding arc line can be established in advance. When all the coordinates of the obstacles are determined, all the coordinates corresponding to the target distance can be determined from the preset corresponding relation to be used as the coordinates of the obstacles, and all the coordinates of the obstacles are determined to be positioned on an arc line taking O as the center of a circle.

The coordinates of all the obstacles are used as reference positions to determine a fifth area Z5 of the detection area where distance information needs to be determined, and the fifth area Z5 is located at an area on one side of the arc line close to the coordinates of the ultrasonic sensor.

In step S253, for each coordinate in the fifth zone Z5, the current distance information of the coordinate is determined according to the historical distance information of the coordinate and the position relationship between the coordinate and all the obstacle coordinates.

In one embodiment, the step S253 of determining the current distance information of the coordinate according to the historical distance information of the coordinate and the position relationship between the coordinate and all the obstacle coordinates includes:

s2531: if the historical distance information is equal to a first set value representing unknown distance, determining target distance information according to the closest distance between the coordinate and the coordinates of all the obstacles, and determining the target distance information as the current distance information of the coordinate;

s2532: if the historical distance information is larger than a first set value and smaller than or equal to a second set value, determining target distance information according to the closest distance between the coordinate and all the coordinates of the obstacle, selecting the optimal distance information S1 from the target distance information and the historical distance information, and determining the optimal distance information S1 as the current distance information of the coordinate;

s2533: and if the historical distance information is larger than the second set value, determining the historical distance information as the current distance information of the coordinate.

In step S2531, the first setting value may be, for example, 0, but the numerical value here is only an example, and may also be other numerical values, such as 1 or 2, and the first setting value represents an unknown distance, and of course, the coordinate may also be regarded as the position of the obstacle. If the historical distance information in the fifth zone Z5 is equal to the first set point, indicating that the distance information for the coordinates has not been modified, the distance is still unknown.

Since an obstacle already exists in the current detection area, a target distance information may be determined according to the closest distance between the coordinate and all the coordinates of the obstacle, and the target distance information may indicate the closest distance between the coordinate and the obstacle, and the closest distance may be proportional to the target distance information, for example, the closer the closest distance, the smaller the target distance information may be, and the target distance information may be determined as the current distance information of the coordinate.

The second setting value may be 127, but the value is only an example, and other values such as 126, 125, 128, etc. if the value is less than or equal to 127, it indicates that the movable platform is too close to the obstacle and cannot pass through.

In step S2532, if the historical distance information is greater than the first setting value and less than or equal to the second setting value, and the first setting value is less than the second setting value, it indicates that the coordinates in the fifth zone Z5 have been modified by the distance information, that is, the existence of the obstacle in front has been detected before and the movable platform cannot pass through the obstacle.

And detecting the obstacle in front again, so that the determined closest distance needs to be determined, determining target distance information according to the closest distance between the coordinate and the coordinates of all the obstacles, selecting the optimal distance information S1 from the target distance information and the historical distance information, wherein the optimal distance information S1 can be the smaller of the target distance information and the historical distance information, and determining the optimal distance information S1 as the current distance information of the coordinate.

In step S2533, if the historical distance information is greater than the second setting value, it indicates that the location is passable, and there is no obstacle in front of the location, and the distance information of the coordinate is continuously maintained, that is, the historical distance information is determined as the current distance information of the coordinate.

In this embodiment, if the distance information of the coordinate is greater than the second set value, the coordinate may be determined as passable; and if the distance information of the coordinate is smaller than the second set value, the coordinate is considered to be not passed, and the smaller the distance information is, the closer the distance information to the obstacle is, the safer the distance information is.

In one embodiment, determining the target distance information equal to or less than the second set value according to the closest distance between the coordinate and all the coordinates of the obstacle includes:

calculating the distance between the coordinate and the second coordinate; the second coordinates are coordinates of the ultrasonic sensor in a second map;

a first difference between the traversed target distance and the calculated distance; the first difference is the closest distance between the coordinate and the coordinates of all the obstacles;

determining the target distance information according to the first difference, wherein the smaller the first difference is, the smaller the target distance information is;

the optimal distance information S1 is the smaller distance information of the target distance information and the historical distance information.

The distance between the coordinate in the fifth zone Z5 and the second coordinate of the ultrasonic sensor in the second map is calculated, and since the target distance is the closest distance of the obstacle to the second coordinate, the first difference between the target distance and the calculated distance is the closest distance of the coordinate to the obstacle.

In other words, the first difference is the closest distance among the distances from the coordinate to all the coordinates of the obstacle, that is, the first distance information is determined according to the closest distance from the coordinate to the obstacle, and the smaller the first difference is, the smaller the calculated target distance information can be, indicating that the target is closer to the obstacle.

For example, if the target distance information is smaller than the historical distance information, the target distance information is used as the optimal distance information S1, and it is ensured that the distance information of the coordinates represents the closest distance of the coordinates from the obstacle.

In one embodiment, in step S250, determining distance information of coordinates within each detection area in the second map according to the target distance of each ultrasonic sensor, further includes:

s254: and if the target distance of the traversed ultrasonic sensor is the distance when no obstacle is detected, determining the current distance information of the coordinate according to the historical distance information of the coordinate and the position relation between the coordinate and the specified boundary of the detection area aiming at each coordinate in the detection area of the ultrasonic sensor of the second map.

Since no obstacle is detected, the distance information for each coordinate in the detection zone should be greater than the second set value, indicating the closest distance of the coordinate from the designated boundary of the detection zone, indicating that the movable platform may pass.

Thus, for each coordinate, the current distance information of the coordinate is determined according to the historical distance information of the coordinate and the position relation between the coordinate and the specified boundary of the detection area.

In step S254, determining current distance information of the coordinate according to the historical distance information of the coordinate and the position relationship between the coordinate and the specified boundary of the detection region includes:

s2541: if the historical distance information is smaller than or equal to a second set value, determining target distance information according to the closest distance between the coordinate and the specified boundary of the detection area, and determining the target distance information as the current distance information of the coordinate;

s2542: if the historical distance information is greater than the second set value, determining target distance information according to the closest distance between the coordinate and the specified boundary of the detection area, selecting optimal distance information S2 from the target distance information and the historical distance information, and determining the optimal distance information S2 as the current distance information of the coordinate.

In step S2541, if the historical distance information of the coordinate indicates that there is an obstacle in front or is not marked but, in fact, no obstacle is detected at this time, it is necessary to modify the distance information of the coordinate, and the target distance information is determined based on the closest distance between the coordinate and the specified boundary of the detection area, the target distance information being greater than the second set value indicating that the coordinate is in a passable state indicating the closest distance of the coordinate to the specified boundary of the detection area.

In step S2542, if the historical distance information is greater than the second setting value, indicating that the distance information of the coordinate in the detection area has been modified and is in a passable state, determining target distance information based on the closest distance of the coordinate to the specified boundary of the detection area, the target distance information being greater than the second setting value indicating that the coordinate is passable, selecting the optimal distance information S2 from the target distance information and the historical distance information, and determining the optimal distance information S2 as the current distance information of the coordinate, ensuring that the distance information of the coordinate represents the closest distance of the coordinate to the specified boundary.

In one embodiment, the specified boundary is a boundary in the detection region whose closest distance to the second coordinate is a maximum measurement range of the ultrasonic sensor; the second coordinates are coordinates of the ultrasonic sensor in a second map;

determining target distance information greater than the second set value according to the closest distance between the coordinate and the specified boundary of the detection area, including:

calculating the distance between the coordinate and the second coordinate;

calculating a second difference between the maximum measuring range and the calculated distance, wherein the second difference is the closest distance between the coordinate and the specified boundary of the detection area;

determining the target distance information according to the second difference, wherein the smaller the second difference is, the smaller the target distance information is, and the target distance information is larger than the second set value;

the optimal distance information S2 is the smaller distance information of the target distance information and the historical distance information.

And calculating the distance between the coordinate and a second coordinate of the ultrasonic sensor in a second map, wherein the maximum measuring range is the nearest distance from the specified boundary to the second coordinate, and the second difference value between the maximum measuring range and the calculated distance is the nearest distance from the coordinate to the specified boundary. Referring to fig. 2, the designated boundary of the detection region of the ultrasonic sensor U is an arc CB.

In other words, the second difference is the closest distance between the coordinate and the coordinates of all points on the specified boundary, that is, the target distance information is the closest distance from the specified boundary according to the coordinate, and the smaller the second difference, the smaller the calculated target distance information is, the closer the target distance information is to the specified boundary is. Of course, the calculated target distance information is still greater than the second set value, indicating that the movable platform can pass through.

After the distance field description map is obtained, a travel route of the movable platform is determined according to the distance field description map. Since the distance information of the coordinates in the distance field description map represents the distance of the coordinates from the specified boundary or the distance of the coordinates from the obstacle, it is possible to determine whether or not the coordinates are too close to the obstacle based on the distance information, and thus it is possible to determine whether or not the respective coordinates are passable. For example, if the distance information is less than or equal to the second set value, the obstacle is considered to be too close to the obstacle and the vehicle cannot pass; and if the distance information is larger than the second set value, the user is considered to be not very close to the barrier and can pass within the safe distance range. Thus, a travel route for the movable platform can be determined from distance information describing coordinates in the map of the distance field.

In one embodiment, determining a travel route of the movable platform in the scene from the probe area description map comprises:

determining a coordinate with maximum distance information as a target coordinate in the distance field description map;

searching coordinates of distance information of which the distance information is larger than a second set value and smaller than the target coordinates in coordinates around the target coordinates of the distance field description map;

if the distance field description map is found, determining the found coordinates as target coordinates, and returning to the operation of finding the coordinates of the distance information of which the distance information is larger than a second set value and smaller than the target coordinates in the coordinates around the target coordinates of the distance field description map;

and if the mobile platform is not found, determining the driving route of the mobile platform by using the determined target coordinates.

In the above manner, the search is started from the coordinate of the maximum distance information, and according to the gradient of the distance information between the coordinates, the coordinate with smaller distance information is gradually searched, of course, the distance information of the searched coordinates is greater than the second set value, and the coordinates less than or equal to the second set value are considered to be unable to pass, and all the found target coordinates can form the driving route of the movable platform. Of course, the manner of determining the travel route is not limited to this.

Specifically, referring to FIG. 4, the distance field description map is divided into a number of grids (each as a coordinate in the map), which may range from 0-255 for distance information. It is understood that 0-255 is merely an example, and the distance from the grid to the obstacle is represented by an 8-bit binary number, but may be represented by a larger number, such as 9 bits, and the corresponding distance information is 0-511.

In this embodiment, when the distance information is smaller than the second set value, the distance is defined as an unsafe distance, the second set value is related to the maximum range of the ultrasonic sensor at that time, and the distance indicated by the second set value may be half the maximum range. For example, when the maximum range is 5m, then the second set value represents 2.5m, and in the case where the range of the distance information of the grid is 0 to 255, the second set value may be 127. The distance information is less than or equal to the second set value, namely the nearest distance is less than or equal to 2.5m, and the distance information is not a safe distance and cannot pass through; the distance information is larger than the second set value, namely the nearest distance is larger than 2.5m, and the distance information is considered to be in a safe distance and can pass through.

It is understood that the second setting value in this embodiment may also represent not half of the maximum measurement range, but one third, two thirds, etc. of the maximum measurement range, and may be used to represent a threshold value of the safety distance, if necessary.

As shown in fig. 4, a plurality of ultrasonic sensors are arranged around the movable platform C1, four ultrasonic sensors U1-U4 are schematically shown in fig. 4, which are arranged in four directions, front, back, left and right, of the platform, and a distance field description map is obtained according to detection data including, but not limited to, the ultrasonic sensors U1-U4, and numerical values in a grid are distance information thereof. Distance information for grids closer to obstacles Barrier1, Barrier2 is less than 127, indicating that movable platform C1 is not passable; and the closer to the obstacles Barrier1, Barrier2, the smaller the distance information.

In fig. 4, the distance information is greater than 127, which indicates that the movable platform C1 can pass through, and a driving route can be determined from the grid where the distance information is located, so that navigation is realized, and obstacles Barrier1 and Barrier2 can be avoided in time. For example, a grid with distance information of 255 is found as a target grid, for example, a grid 255 on the upper left of U1, a target grid with distance information of 254 is found, a target grid with distance information of 253 is found, and so on, and the driving route of the movable platform is determined by using the found grids.

It is understood that the size and density of the grid and the distance division accuracy of the ultrasonic sensor are related, for example, in the case that the maximum measurement range is 5 meters and the distance division accuracy is high, the grid is many, small and dense, and is not limited to the example shown in fig. 4.

In one embodiment, determining a target distance associated with a scene within a detection zone of the ultrasonic sensor from detection data of the ultrasonic sensor comprises:

s201: acquiring M pieces of historical detection data detected by the ultrasonic sensor before the detection data, wherein M is more than or equal to 1;

s202: calculating median values of the probe data and the M historical probe data;

s203: determining a median value as the target distance.

The detection data obtained by the ultrasonic sensor has a flicker characteristic, that is, abnormal data can appear in the detection data, but generally, the possibility of continuous appearance of the abnormal data is low, so in the embodiment, the median value between the current detection data and the M pieces of historical detection data is used as the target distance for determining the detection area state, and the abnormal data appearing in the use process of the ultrasonic sensor can be effectively removed.

Since it is generally impossible for the ultrasonic sensor to continuously generate more than 3 frames of abnormality detection data, M is preferably equal to 4 or greater than 4 in the present embodiment.

In one embodiment, determining a target distance associated with a scene within a detection region of the ultrasonic sensor from detection data of the ultrasonic sensor comprises:

s204: acquiring M pieces of historical detection data detected by the ultrasonic sensor before the detection data, wherein M is more than or equal to 1;

s205: calculating median values of the probe data and the M historical probe data;

s206: if the median is the distance when the obstacle is detected, performing smooth filtering processing on the median;

s207: and determining the smooth filtering processing result as the target distance.

In this embodiment, on the basis of removing the abnormal data, if the median is the distance when the obstacle is detected, the calculated median is further subjected to smoothing filtering, and the result of the smoothing filtering is determined as the target distance. The finally obtained target distance can be more stable, and the fluctuation is further reduced.

In one embodiment, in step S206, the smoothing filter processing is performed on the median value, and includes:

s2061: acquiring N historical median values of the ultrasonic sensor determined before the median value, wherein N is greater than or equal to 1;

s2062: calculating the mean value of the median value and N historical median values;

in step S207, determining the result of the smoothing filter processing as the target distance includes:

determining the mean as the target distance.

Preferably, N may be equal to 6, or greater than 6, and of course, N is not limited in the embodiments of the present specification. Likewise, so does M.

For a better understanding, the following is described by way of a more complete example, but not by way of limitation. In this embodiment, a movable platform is taken as an example for explanation.

After acquiring current detection data of a plurality of ultrasonic sensors, in order to eliminate the distance flicker characteristic, firstly, the following processing is carried out on the detection data of each ultrasonic sensor, and a target distance related to the detection area state of the ultrasonic sensor is obtained:

step A101, obtaining M pieces of historical detection data detected by the ultrasonic sensor before current detection data, and calculating median values of the current detection data and the M pieces of historical detection data;

step A102, if the median is the distance when the obstacle is detected, obtaining N historical median values of the ultrasonic sensor determined before the median, calculating the mean value of the median and the N historical median values, and taking the mean value as the target distance; and if the median value is the distance when no obstacle is detected, taking the median value as the target distance.

After the target distance of each ultrasonic sensor is determined, a detection area description map can be generated according to the target distance of each ultrasonic sensor, and the detection area state of each ultrasonic sensor is determined in the detection area description map. The probe region description map includes a state description map, and/or a distance field description map.

The state description map describes three discrete states of the detection area, namely an impassable state indicating occupancy by an obstacle, a passable state indicating non-occupancy by the obstacle and an unknown state, and three discrete values can be used for representing the three states, for example, 0 represents the unknown state, 127 represents the passable state, and 255 represents the impassable state.

The distance field description map may characterize the closest distance of a coordinate to an obstacle, or to a specified boundary of a detection region, by continuous distance information. For example, the distance information is less than or equal to the second set value, which indicates an impassable state, and the smaller the value, the closer the distance to the obstacle, the greater the probability of impassability; the distance information is larger than the second set value, indicating a passable state, and the larger the value is, indicating that the farther the distance from the obstacle or the specified boundary is, the larger the passable probability is.

Before the state description map and the distance field description map are generated, an ultrasonic coordinate system may be established, a detection region of each ultrasonic sensor may be determined in the ultrasonic coordinate system, coordinates corresponding to each detection data (for example, detection data 0.2 to 4m from the start point, and resolution may be 0.01m) in the detection region may be determined using the corresponding ultrasonic sensor as a start point in the ultrasonic coordinate system, and the detection data and the corresponding coordinates may be recorded in a distance coordinate table. The detection area may be shaped like a pear as shown in fig. 2, one detection datum may correspond to a plurality of coordinates, and the coordinates corresponding to the same detection datum form an arc area with the center of the circle being O.

The manner in which the state description map is generated is described in detail below:

step a103, creating a first map and initializing a coordinate state in the first map. Wherein the initializing the coordinate state in the first map comprises setting the coordinate state in the first map to an unknown state. Setting the coordinate state in the first map to an unknown state includes representing state information in the map using 0.

First, an inaccessible state in the detection area of each ultrasonic sensor in the first map is determined based on the target distance.

Step A111, traversing the target distance of each ultrasonic sensor; the plurality of ultrasonic sensors may be annularly disposed on the vehicle, and the target distances of the respective ultrasonic sensors may be traversed in a clockwise or counterclockwise order according to the positions of the respective ultrasonic sensors on the vehicle.

Step a112, if the target distance of the traversed ultrasonic sensor is the distance when the obstacle is detected, determining a sub-region corresponding to the target distance in the detection region of the ultrasonic sensor in the first map, determining all coordinates corresponding to the target distance in the distance coordinate table, locating the sub-region in the detection region from all the coordinates, where the sub-region is an arc region and may have a thickness of 0.02m (the target distance is represented by dist, and the region in the detection region within a range from the starting point dist to dist +0.02m is a sub-region), and modifying the state of the sub-region in the first map from the identified unknown state to the non-passing state.

In step a113, if the target distance of the traversed ultrasonic sensor is the distance when no obstacle is detected, no processing is performed on the detection region of the ultrasonic sensor.

Then, the passing state of the detection area of each ultrasonic sensor in the first map with the identified non-passing state is determined according to the target distance. And the detection areas of two adjacent ultrasonic sensors in the first map have an intersection area.

Step a114, the target distances of the respective ultrasonic sensors are traversed.

Step A115, if the object distance of the traversed ultrasonic sensor is the distance when the obstacle is detected, determining a sub-area corresponding to the object distance in the detection area of the ultrasonic sensor in the first map, wherein the sub-area can be determined in the same manner as the above, and determining a first local area and a second local area in the sub-area, wherein the first local area is located in a designated intersection area of the detection area, the second local area is located in a non-intersection area of the detection area, the first local area is shown as X3 in FIG. 3, the second local area is shown as X2 in FIG. 3, and X1-X3 form a sub-area; the specified intersection region may be an intersection region between the current detection region and the next detection region.

Checking whether a target local area which is out of the first local area and has a non-passing state exists in the designated intersection area or not aiming at the first local area; if so, as in fig. 3, a target local area X4 exists in the designated intersection area, the distance from the first local area to a first coordinate, which is the coordinate of the ultrasonic sensor in the first map, as in fig. 3, the distance from the target local area to the first coordinate, is compared with the distance from the target local area to the first coordinate, as in fig. 3, the coordinate of U2, the local area farther from the comparison result is used as a reference position to determine a first area Z1 to be adjusted in the designated intersection area, and the state of the first area Z1 is adjusted to a passable state, and if not, the second area Z2 to be adjusted in the designated intersection area is determined with the first local area as the reference position, and the state of the second area Z2 is modified from an unknown state to a passable state.

As shown in fig. 3, the distance of X3 from the first coordinate of the ultrasonic sensor U2 is shorter than the distance of X4 from the first coordinate, and thus, a first region Z1 is determined with X4 as a reference position, and this Z1 is a region on one side of the designated intersection region which is located on X4 near the first coordinate.

Since the first region Z1 includes the first local region, there are two states, the non-passing state and the unknown state. The state of the first zone Z1 is adjusted to a passable state, including: the state of the local region closer to the comparison result in the first region Z1 is modified from the non-passable state to the passable state, and the states of the regions other than the local region closer to the comparison result in the first region Z1 are modified from the unknown state to the passable state. Continuing with fig. 3, in a region (first region Z1) in which the designated intersection region is located on the side of the coordinates of X4 near U2, the state of the first local region X3 is modified from the non-passable state to the passable state, and the states of the regions other than X3 are modified from the unknown state to the passable state.

And for the second local area, determining a third area Z3 to be adjusted in the non-intersection area by taking the second local area as a reference position, and modifying the state of the third area Z3 from an unknown state to a passable state. With continued reference to fig. 3, the third region Z3 is a region on one side of the second local region X2 close to the first coordinate U2 in the non-intersection region of the detection region, and since all states are unknown states, the states of the coordinates in Z3 are modified from unknown states to passable states.

Step a116, if the target distance of the traversed ultrasonic sensor is the distance when no obstacle is detected, adjusting the detection area state of the ultrasonic sensor in the first map to a passable state.

Since the detection area state may exist in both an impassable state and an unknown state, or may exist in only one of the unknown states, the adjusting of the detection area state of the ultrasonic sensor in the first map to a passable state includes: checking whether the detection area has a fourth area Z4 identified as a non-passable state; if so, modifying the state of the fourth zone Z4 in the detection zone from an unobstructable state to a passable state, and modifying the state of the zone outside the fourth zone Z4 in the detection zone from an unknown state to a passable state; if not, the state of the detection area is modified from an unknown state to a passing state.

And determining the first map with the determined passable state as a state description map, and determining a driving route of the next step for the vehicle according to the state description map.

The following details the way distance field describes the map determination:

step a120, creating a second map and initializing distance information of coordinates in the second map. Wherein the initializing distance information in the second map includes setting coordinate distance information in the second map to a first setting value. Setting the coordinate distance information in the second map as the first setting value includes representing the distance information of the coordinates in the map using 0.

Step A121: traversing the target distance of each ultrasonic sensor;

step A122: if the target distance of the traversed ultrasonic sensor is the distance when the obstacle is detected, at least one obstacle coordinate corresponding to the target distance is determined in the detection area of the ultrasonic sensor on the second map, a fifth area Z5, in which the distance information of the characteristic state needs to be determined, is determined by taking all the obstacle coordinates as reference positions, and for each coordinate in the fifth area Z5, the current distance information of the coordinate is determined according to the historical distance information of the coordinate and the position relationship between the coordinate and all the obstacle coordinates.

The coordinates corresponding to the target distance can be searched in the distance coordinate table, and all the searched coordinates are determined as the coordinates of the obstacle. All the coordinates of the obstacles found are in the form of an arc in the detection area, and the fifth area Z5 is an area on one side of the detection area near the second coordinate of the ultrasonic sensor in the second map.

The second map is described by distance information, for each coordinate in the fifth zone Z5, the current distance information needs to be determined. Determining the current distance information of the coordinate according to the historical distance information of the coordinate and the position relationship between the coordinate and all the obstacle coordinates, wherein the method comprises the following three conditions:

and in the first case, if the historical distance information is equal to a first set value representing unknown distance, determining target distance information according to the closest distance between the coordinate and all the obstacle coordinates, and determining the target distance information as the current distance information of the coordinate.

The first set value, which characterizes the unknown distance, is for example 0. Assuming that the distance between the coordinate and the second coordinate is d1, and the target distance is represented by dist, the target distance information can be calculated by the following formula: 127 (dist-d 1)/4.

The first difference (dist-d 1) is the closest distance among the distances from the coordinate to the coordinates of each obstacle, i.e. the object distance information is determined according to the closest distance from the coordinate to the obstacle, the smaller the closest distance, i.e. the smaller the first difference, the smaller the first distance information. Of course, if the calculated target distance information is greater than 127, indicating that it is at a safe distance, the movable platform may pass, whereas if the calculated target distance information is less than or equal to 127, indicating that it is not at a safe distance, the movable platform may not pass.

And in the second case, if the historical distance information is larger than the first set value and smaller than or equal to a second set value, determining target distance information according to the closest distance between the coordinate and all the obstacle coordinates, selecting the optimal distance information S1 from the target distance information and the historical distance information, and determining the optimal distance information S1 as the current distance information of the coordinate.

In this case, the formula for calculating the target distance information may also be the following formula: 127 (dist-d 1)/4. The optimum distance information S1 may be the smaller value of the target distance information and the history distance information, that is, the distance information determined according to the closest distance to the obstacle is recorded on the coordinates.

And thirdly, if the historical distance information is larger than the second set value, determining the historical distance information as the current distance information of the coordinate.

The historical distance information is greater than the second set value, indicating that the movable platform is passable, and the distance information of the coordinates is maintained as the historical distance information, indicating that the movable platform is still passable.

Step A123: and if the target distance of the traversed ultrasonic sensor is the distance when no obstacle is detected, determining the current distance information of the coordinate according to the historical distance information of the coordinate and the position relation between the coordinate and the specified boundary of the detection area aiming at each coordinate in the detection area of the ultrasonic sensor of the second map.

The boundary is specified to have the nearest distance from the second coordinate as the maximum range of the ultrasonic sensor, namely, the boundary which can be detected by the maximum range of the ultrasonic sensor in the detection area.

The second map is described by distance information, and when no obstacle is detected in the detection area, the current distance information to be identified needs to be determined for each coordinate of the detection area. Determining the current distance information of the coordinate according to the historical distance information of the coordinate and the position relation between the coordinate and the specified boundary of the detection area, wherein the method comprises the following two conditions:

and in the first case, if the historical distance information is less than or equal to a second set value, determining target distance information according to the closest distance between the coordinate and the specified boundary of the detection area, and determining the target distance information as the current distance information of the coordinate.

Assuming that the coordinate is at a distance d2 from the second coordinate, and the maximum measurement range is denoted by dmax, the second distance information can be calculated by the following formula: 128+127 (dmax-d)/4.

The second difference (dmax-d) is the closest distance of the coordinate to the specified boundary, and the smaller the closest distance, i.e., the smaller the second difference, the smaller the target distance information. Of course, the calculated target distance information is necessarily greater than the second set value, indicating that the movable platform can pass through.

And in the second case, if the historical distance information is larger than the second set value, determining target distance information according to the closest distance between the coordinate and the specified boundary of the detection area, selecting the optimal distance information S2 from the target distance information and the historical distance information, and determining the optimal distance information S2 as the current distance information of the coordinate.

In this case, the formula for calculating the target distance information may also be the following formula: 128+127 (dmax-d)/4. The optimum distance information S2 may be smaller distance information of the target distance information and the history distance information, that is, distance information determined according to the closest distance to the specified boundary is recorded on the coordinates.

After traversing all the target distances, determining the processed second map as a distance field description map, and determining a next driving route for the vehicle according to the distance field description map.

Of course, the state description map and the distance field description map may be combined to determine a next travel route for the vehicle.

Based on the same concept as the method described above, referring to fig. 5, the present specification further provides an electronic device 100, including: a memory 101 and a processor 102 (e.g., one or more processors).

The memory for storing program code;

the processor is configured to call the program code, and when the program code is executed, the processor is configured to execute the navigation method of the movable platform according to the foregoing embodiment.

Based on the same inventive concept as the above method, an embodiment of the present specification further provides a computer-readable storage medium, where computer instructions are stored, and when the computer instructions are executed, the navigation method of the movable platform described in the foregoing embodiment is implemented.

The systems, devices, modules or units illustrated in the above embodiments may be implemented by a computer chip or an entity, or by an article of manufacture with certain functionality. A typical implementation device is a computer, which may take the form of a personal computer, laptop computer, cellular telephone, camera phone, smart phone, personal digital assistant, media player, navigation device, email messaging device, game console, tablet computer, wearable device, or a combination of any of these devices.

For convenience of description, the above devices are described as being divided into various units by function, and are described separately. Of course, the functions of the various elements may be implemented in the same one or more software and/or hardware implementations of the present description.

As will be appreciated by one skilled in the art, the present specification embodiments may be provided as a method, system, or computer program product. Accordingly, the description may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, embodiments of the present description may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and so forth) having computer-usable program code embodied therein.

The description has been presented with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the description. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

Furthermore, these computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

The above description is only an example of the present specification, and is not intended to limit the present specification. Various modifications and alterations to this description will become apparent to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present specification should be included in the scope of the claims of the present specification.