阅读说明：本技术 绕机检查装置及其定位方法、存储介质 (Winding inspection device, positioning method thereof and storage medium ) 是由 吕品 季博文 赖际舟 卢坤 陆建 徐扬 于 2020-07-16 设计创作，主要内容包括：本申请公开了一种绕机检查装置及其定位方法、可读存储介质。控制绕机检查装置围绕飞机运行,根据获取不同时刻的机轮的激光雷达点云建立飞机坐标系下机轮的激光雷达点云地图；在检查过程中,将在绕机检查装置坐标系下的机轮的激光雷达点云与所述激光雷达点云地图进行点云匹配,得到所述机轮的激光雷达点云在所述绕机检查装置坐标系转换至所述飞机坐标系的转换矩阵；根据所述转换矩阵确定所述绕机检查装置在飞机坐标系下的位姿。解决了现有技术中通过GPS定位方法确定绕机检查装置位姿信息存在不准确的问题。(The application discloses a winding machine inspection device, a positioning method thereof and a readable storage medium. Controlling the winding inspection device to run around the airplane, and establishing a laser radar point cloud map of the airplane wheels under an airplane coordinate system according to the obtained laser radar point clouds of the airplane wheels at different moments; in the checking process, carrying out point cloud matching on the laser radar point cloud of the airplane wheel under the coordinate system of the winding checking device and the laser radar point cloud map to obtain a conversion matrix for converting the laser radar point cloud of the airplane wheel to the airplane coordinate system in the coordinate system of the winding checking device; and determining the pose of the winding inspection device in an airplane coordinate system according to the transformation matrix. The problem of inaccurate in determining the position and orientation information of the winding inspection device through a GPS positioning method in the prior art is solved.)

1. A method of positioning a winding inspection device, the method comprising:

controlling the winding inspection device to run around the airplane, and establishing a laser radar point cloud map of the airplane wheels under an airplane coordinate system according to the obtained laser radar point clouds of the airplane wheels at different moments;

in the checking process, carrying out point cloud matching on the laser radar point cloud of the airplane wheel under the coordinate system of the winding checking device and the laser radar point cloud map to obtain a conversion matrix for converting the laser radar point cloud of the airplane wheel to the airplane coordinate system in the coordinate system of the winding checking device;

and determining the pose of the winding inspection device in an airplane coordinate system according to the transformation matrix.

2. The method of claim 1, wherein the step of point cloud matching the acquired laser radar point cloud of the wheel under the coordinate system of the inspection device to the laser radar point cloud map to obtain the transformation matrix of the laser radar point cloud of the wheel in the coordinate system of the inspection device to the coordinate system of the airplane comprises:

when the winding machine inspection device is at an initial inspection time, acquiring laser radar point cloud of the airplane wheel under a winding machine inspection device coordinate system at the initial inspection time;

and performing point cloud matching on the laser radar point cloud of the airplane wheel and the laser radar point cloud map to obtain a conversion matrix for converting the laser radar point cloud of the airplane wheel to the airplane coordinate system in the winding inspection device coordinate system at the initial inspection moment.

3. The method of claim 2, wherein the step of point cloud matching the lidar point cloud of the wheel under the onboard inspection apparatus coordinate system to the lidar point cloud map to obtain a transformation matrix for transforming the lidar point cloud of the wheel to the aircraft coordinate system under the onboard inspection apparatus coordinate system further comprises:

when the winding machine inspection device is at a non-initial inspection time, acquiring laser radar point cloud of the airplane wheel under a winding machine inspection device coordinate system at the current time;

converting the laser radar point cloud according to the pose of the winding inspection at the last moment in an airplane coordinate system to obtain an original laser radar point cloud;

and performing point cloud matching on the original laser radar point cloud and the laser radar point cloud map to obtain a conversion matrix for converting the laser radar point cloud of the airplane wheel at the current moment into the airplane coordinate system in the winding inspection device coordinate system.

4. The method of positioning a winding inspection device according to claim 3, wherein the step of determining the pose of the winding inspection device in an aircraft coordinate system from the transformation matrix comprises:

if the winding inspection device is at the initial inspection time, determining a first pose of the winding inspection device under an airplane coordinate system at the initial inspection time according to a transformation matrix of the initial inspection time;

and if the winding inspection device is at the non-initial inspection time, determining a first pose of the winding inspection device at the current time in an airplane coordinate system according to the conversion matrix at the current time.

5. The method of positioning a winding inspection device according to claim 4, wherein the step of determining the first pose of the winding inspection device in the aircraft coordinate system according to the transformation matrix is followed by:

acquiring the pose of the winding inspection device in an SLAM coordinate system;

judging whether the vehicle winding inspection device is at an initial moment or not;

if the winding inspection device is at an initial inspection time, acquiring a first pose of the initial inspection time, and converting the pose of the winding inspection device at the initial time under an SLAM coordinate system into a pose under an airplane coordinate system;

and if the winding inspection device is at the non-initial inspection time, acquiring the pose of the winding inspection device under the airplane coordinate system at the previous time of the current time, and converting the pose of the winding inspection device under the SLAM coordinate system at the current time into a second pose under the airplane coordinate system.

6. The method of positioning a winding inspection device according to claim 5, wherein the step of determining the first pose of the winding inspection device in the aircraft coordinate system according to the transformation matrix further comprises:

judging whether a first position and a second position of the winding inspection device at the current moment are accurate or not according to data information of an inertial sensor of the winding inspection device and a vehicle-mounted odometer;

if the pose of the winding inspection device is accurate, performing data fusion on the first pose and the second pose at the current moment, inertial sensor data and vehicle-mounted mileage data by using extended Kalman filtering to obtain a more accurate pose of the winding inspection device in an airplane coordinate system;

and if the attitude of the winding inspection device is inaccurate, acquiring the attitude of the winding inspection device obtained by recursion of the inertial sensor and the vehicle-mounted odometer as the attitude of the winding inspection device in the airplane coordinate system at the current moment.

7. The positioning method of the winding inspection device according to claim 6, wherein the step of determining whether the first position and the second position of the winding inspection device at the current time are accurate comprises:

and respectively comparing the first position and the second position of the winding inspection device at the current moment with the predicted position and posture of the current moment, and if the calculated difference is within a preset range, determining that the first position and the second position at the current moment are accurate.

8. The method of claim 1, wherein the step of obtaining the lidar point cloud for the wheels at different times comprises:

controlling the winding inspection device to run around the airplane and collecting laser radar points;

clustering the scanning points, and screening the clustered laser radar points according to the relative distance of the airplane wheels to obtain laser radar point cloud of the airplane wheels;

and acquiring laser radar points at different moments, executing the clustering, screening the clustered laser radar points according to the relative distance of the airplane wheels to obtain the laser radar point cloud of the airplane wheels, so as to obtain the laser radar point cloud of the airplane wheels at different moments.

9. A winder inspection apparatus, the apparatus comprising:

the acquisition module is used for acquiring a global point cloud coordinate of a scanning device of the winding inspection device for scanning the airplane wheel in an airplane coordinate system;

the conversion module is used for converting the global point cloud coordinate and a point cloud coordinate of a scanning airplane wheel based on an apparatus coordinate system in the process of winding inspection;

and the determining module is used for determining the pose of the winding inspection device in an airplane coordinate system according to the conversion result.

10. A computer-readable storage medium, on which a positioning program of a winding inspection apparatus is stored, characterized in that the positioning program of the winding inspection apparatus realizes the steps of the method of any one of claims 1 to 8 when executed by a processor.

Technical Field

The application relates to the technical field of laser radar positioning, in particular to a winding machine inspection device, a positioning method and a storage medium thereof.

Background

The airplane becomes an indispensable transportation tool for people to go out due to the characteristics of high speed, high safety and the like. In order to ensure the navigation safety of the airplane, safety inspection before flight is an essential link. However, because the safety inspection time before flight is short and the task is heavy, the manual inspection is inevitable and careless, and the efficiency and reliability of the manual inspection are also reduced due to the influence of the environment. For manual inspection, the efficiency and the reliability of inspection can be improved by using a ground unmanned vehicle or an unmanned machine for inspection, and the recorded images are convenient to reappear afterwards when the inspection is performed.

At present, in an outdoor environment, a satellite/inertial sensor fusion method is mainly adopted for positioning a ground unmanned vehicle, but in the process of passenger plane patrol inspection, a satellite refusal environment exists, so that the reliability of positioning by using a GPS is low. In a factory environment, an unmanned vehicle generally adopts a mode of paving a guide rail or a magnetic strip in advance for navigation, but the method is more complicated, the track is difficult to change, and the method is not suitable for an airport environment.

Disclosure of Invention

The embodiment of the application aims to solve the problem that when the conventional method of fusing a satellite/inertial sensor is adopted to position the flight inspection device, the positioning of the flight inspection device is inaccurate due to the existence of a satellite refused environment in the process of inspecting the passenger plane.

In order to achieve the above object, an aspect of the present application provides a positioning method of a winding inspection apparatus, including:

controlling the winding inspection device to operate around the airplane, and establishing a laser radar point cloud map of the airplane wheels under an airplane coordinate system according to the obtained laser radar point clouds of the airplane wheels at different moments;

in the checking process, carrying out point cloud matching on the laser radar point cloud of the airplane wheel under the coordinate system of the winding checking device and the laser radar point cloud map to obtain a conversion matrix for converting the laser radar point cloud of the airplane wheel to the coordinate system of the airplane in the coordinate system of the winding checking device;

and determining the pose of the winding inspection device in an airplane coordinate system according to the transformation matrix.

Optionally, the step of performing point cloud matching on the acquired laser radar point cloud of the wheel under the winding inspection device coordinate system and the laser radar point cloud map to obtain a conversion matrix for converting the laser radar point cloud of the wheel to the aircraft coordinate system in the winding inspection device coordinate system includes:

when the winding machine inspection device is at an initial inspection time, acquiring laser radar point cloud of the airplane wheel under a winding machine inspection device coordinate system at the initial inspection time;

and performing point cloud matching on the laser radar point cloud of the airplane wheel and the laser radar point cloud map to obtain a conversion matrix for converting the laser radar point cloud of the airplane wheel to the airplane coordinate system in the winding inspection device coordinate system at the initial inspection moment.

Optionally, the step of performing point cloud matching on the laser radar point cloud of the wheel under the winding inspection device coordinate system and the laser radar point cloud map to obtain a conversion matrix for converting the laser radar point cloud of the wheel to the aircraft coordinate system in the winding inspection device coordinate system further includes:

when the winding machine inspection device is at a non-initial inspection time, acquiring laser radar point cloud of the airplane wheel under a winding machine inspection device coordinate system at the current time;

converting the laser radar point cloud according to the pose of the winding inspection at the last moment in an airplane coordinate system to obtain an original laser radar point cloud;

and performing point cloud matching on the original laser radar point cloud and the laser radar point cloud map to obtain a conversion matrix for converting the laser radar point cloud of the airplane wheel to the airplane coordinate system in the winding inspection device coordinate system at the current moment.

Optionally, the step of determining the pose of the orbiting inspection device in the aircraft coordinate system according to the transformation matrix includes:

if the winding inspection device is at the initial inspection time, determining a first pose of the winding inspection device under an airplane coordinate system at the initial inspection time according to a transformation matrix of the initial inspection time;

and if the winding inspection device is at the non-initial inspection time, determining a first pose of the winding inspection device at the current time in an airplane coordinate system according to the conversion matrix at the current time.

Optionally, after the step of determining the first pose of the orbiting checking device in the airplane coordinate system according to the transformation matrix, the method includes:

acquiring the pose of the winding inspection device in an SLAM coordinate system;

if the winding inspection device is at an initial inspection time, acquiring a first pose of the initial inspection time, and converting the pose of the winding inspection device at the initial time under an SLAM coordinate system into a pose under an airplane coordinate system;

and if the winding inspection device is at the non-initial inspection time, acquiring the pose of the winding inspection device under the airplane coordinate system at the previous time of the current time, and converting the pose of the winding inspection device under the SLAM coordinate system at the current time into a second pose under the airplane coordinate system.

Optionally, after the step of determining the first pose of the orbiting checking device in the airplane coordinate system according to the transformation matrix, the method further includes:

judging whether a first position and a second position of the winding inspection device at the current moment are accurate or not according to data information of an inertial sensor of the winding inspection device and a vehicle-mounted odometer;

judging whether a first position and a second position of the winding inspection device at the current moment are accurate or not according to data information of an inertial sensor of the winding inspection device and a vehicle-mounted odometer;

if the pose of the winding inspection device is accurate, performing data fusion on the first pose and the second pose at the current moment, inertial sensor data and vehicle-mounted mileage data by using extended Kalman filtering to obtain a more accurate pose of the winding inspection device in an airplane coordinate system;

and if the attitude of the winding inspection device is inaccurate, acquiring the attitude of the winding inspection device obtained by recursion of the inertial sensor and the vehicle-mounted odometer as the attitude of the winding inspection device in the airplane coordinate system at the current moment.

Optionally, the step of determining whether the first position and the second position of the winding inspection device at the current time are accurate includes:

and respectively comparing the first position and the second position of the winding inspection device at the current moment with the predicted position and posture of the current moment, and if the calculated difference is within a preset range, determining that the first position and the second position at the current moment are accurate.

Optionally, the step of acquiring the lidar point cloud of the wheel at different times includes:

controlling the winding inspection device to run around the airplane and collecting laser radar points;

clustering the scanning points, and screening the clustered laser radar points according to the relative distance of the airplane wheels to obtain laser radar point cloud of the airplane wheels;

and acquiring laser radar points at different moments, executing the clustering, screening the clustered laser radar points according to the relative distance of the airplane wheels to obtain the laser radar point cloud of the airplane wheels, and thus obtaining the laser radar point cloud of the airplane wheels at different moments.

In addition, to achieve the above object, another aspect of the present application further provides a winding inspection apparatus, including:

the acquisition module is used for acquiring a global point cloud coordinate of a scanning device of the winding inspection device for scanning the airplane wheel in an airplane coordinate system;

the conversion module is used for converting the global point cloud coordinate and a point cloud coordinate of a scanning airplane wheel based on an apparatus coordinate system in the process of winding inspection;

and the determining module is used for determining the position and the posture of the winding inspection device under an airplane coordinate system according to the conversion result.

In order to achieve the above object, another aspect of the present application provides a computer-readable storage medium, which is characterized by storing thereon a positioning program of a winding inspection apparatus, the positioning program of the winding inspection apparatus implementing the steps of the method according to any one of the above when executed by a processor.

The method comprises the steps of firstly running around an airplane to be inspected when the winding inspection device is inspected around the airplane, acquiring laser radar point clouds of airplane wheels at different moments through laser scanning equipment of the winding inspection device, establishing a laser radar point cloud map of the airplane wheels under an airplane coordinate system, carrying out point cloud matching on the acquired laser radar point clouds of the airplane wheels under the winding inspection device coordinate system and the laser radar point cloud map in the inspection process, obtaining a conversion matrix for converting the laser radar point clouds of the airplane wheels to the airplane coordinate system under the winding inspection device coordinate system, and determining the pose of the winding inspection device under the airplane coordinate system according to the conversion matrix. By the mode, when the position and the pose of the winding inspection device in the winding inspection process are determined, positioning systems such as a GPS (global positioning system) and the like are not needed, so that the problem that when the position and the pose of the winding inspection device are determined by the GPS is avoided, the positioning of the winding inspection device is inaccurate due to the existence of a satellite refusing environment, and the effect of improving the positioning accuracy of the winding inspection device in the process of executing the inspection task is achieved.

Drawings

FIG. 1 is a schematic structural diagram of an apparatus according to an embodiment of the present disclosure;

FIG. 2 is a schematic flow chart illustrating an embodiment of a positioning method for a winding inspection apparatus according to the present application;

FIG. 3 is a detailed flowchart of the positioning method step S20 of the winding inspection device according to the present application;

FIG. 4 is a detailed flowchart of the positioning method step S20 of the winding inspection device according to the present application;

FIG. 5 is a schematic flow chart illustrating another embodiment of the positioning method for the winding inspection apparatus according to the present application;

fig. 6 is a schematic flowchart of another embodiment of the positioning method of the winding inspection device according to the present application.

The implementation, functional features and advantages of the objectives of the present application will be further explained with reference to the accompanying drawings.

Detailed Description

The main solution of the embodiment of the application is as follows: controlling the winding inspection device to run around the airplane, and establishing a laser radar point cloud map of the airplane wheels under an airplane coordinate system according to the obtained laser radar point clouds of the airplane wheels at different moments; in the checking process, carrying out point cloud matching on the laser radar point cloud of the airplane wheel under the coordinate system of the winding checking device and the laser radar point cloud map to obtain a conversion matrix for converting the laser radar point cloud of the airplane wheel to the coordinate system of the airplane in the coordinate system of the winding checking device; and determining the pose of the winding inspection device in an airplane coordinate system according to the transformation matrix.

In the prior art, a satellite/inertial sensor fusion method is mainly adopted for positioning the flight inspection device, but when an environment where a satellite rejects exists in the process of inspecting the passenger plane, the reliability of positioning the flight inspection device is reduced.

The present invention provides the above solution, aiming to improve the positioning accuracy of the winding inspection device.

The embodiment of the application provides a winding machine inspection device, which comprises a laser radar sensor, a supporting part and a control circuit. The laser radar sensor is used for scanning an airplane wheel to form laser radar point cloud of the airplane wheel, the supporting part is used for supporting equipment built in the winding inspection device when the winding inspection device performs inspection tasks around the airplane, and the control circuit is used for controlling the winding inspection device to perform control operations such as winding inspection.

In the embodiment of the present application, as shown in fig. 1, fig. 1 is a schematic terminal structure diagram of a hardware operating environment of a device according to an embodiment of the present application.

As shown in fig. 1, the terminal may include: a processor 1001, such as a CPU, a network interface 1004, a user interface 1003, a memory 1005, a communication bus 1002. Wherein a communication bus 1002 is used to enable connective communication between these components. The user interface 1003 may include a Display screen (Display), an input unit such as a Keyboard (Keyboard), and the optional user interface 1003 may also include a standard wired interface, a wireless interface. The network interface 1004 may optionally include a standard wired interface, a wireless interface (e.g., WI-FI interface). The memory 1005 may be a high-speed RAM memory or a non-volatile memory (e.g., a magnetic disk memory). The memory 1005 may alternatively be a storage device separate from the processor 1001.

Those skilled in the art will appreciate that the terminal structure shown in fig. 1 does not constitute a limitation of the terminal device and may include more or fewer components than those shown, or some components may be combined, or a different arrangement of components.

As shown in fig. 1, a memory 1005, which is a kind of computer-readable storage medium, may include therein an operating system, a network communication module, a user interface module, and a positioning program of the by-pass inspection apparatus.

The application also provides a positioning method of the winding machine inspection device.

Referring to fig. 2, an embodiment of a positioning method of the winding inspection device of the present application is provided. In this embodiment, the positioning method of the winding inspection apparatus includes:

step S10, controlling the winding inspection device to operate around the airplane, and establishing a laser radar point cloud map of the airplane wheel under the airplane coordinate system according to the obtained laser radar point clouds of the airplane wheels at different moments;

before the winding inspection, the winding inspection device is controlled to run around the airplane for one circle, wherein the winding inspection device can be embodied as a winding inspection device provided with a laser radar in the application. Before the winding inspection device performs winding inspection, the method for establishing the laser radar point cloud map under the airplane coordinate system by acquiring the laser radar point cloud of the airplane wheel at different moments can be used for constructing the map in a field acquisition mode and can also be used for constructing the map in a simulation environment (a three-dimensional model of the airplane is built in the simulation environment, and the winding inspection device is controlled to wind around the airplane of the three-dimensional model).

The plane coordinate system can be specifically established by taking the center of a front wheel of the plane as an origin, pointing the y axis to the tail along the longitudinal axis of the plane, and vertically and rightwards establishing the x axis.

In the application, a laser radar point cloud map of the wheel is firstly constructed, and the laser radar point cloud map of the wheel is formed by that before the winding inspection, the winding inspection device winds around the airplane to obtain the laser radar point cloud of the wheel at different moments, which can be understood as the preparation work of the winding inspection device in executing the winding inspection task.

The step of obtaining the laser radar point cloud of the airplane wheel at different moments comprises the following steps:

step S11, controlling the winding inspection device to run around the airplane and collecting laser radar points;

step S12, clustering the scanning points, and screening the laser radar points after clustering according to the relative distance of the airplane wheels to obtain laser radar point cloud of the airplane wheels;

and step S13, acquiring laser radar points at different moments, executing the clustering, screening the clustered laser radar points according to the relative distance of the airplane wheels to obtain the laser radar point cloud of the airplane wheels, so as to obtain the laser radar point cloud of the airplane wheels at different moments.

In the process of acquiring the laser radar point of the wheel by the winding inspection device around the airplane (including constructing the laser radar point cloud map of the wheel and acquiring the laser radar point cloud of the wheel in the process of executing the winding inspection task), the laser radar points obtained by the laser scanning device are not all the laser radar points of the wheel (scanned to the wheel)Laser radar point clouds of wings, a fuselage, an empennage, or the like), so that the laser radar point clouds of the airplane wheels need to be screened, wherein the laser radar point clouds are a collection consisting of a plurality of laser radar points. And clustering the laser radar point cloud data by using a nearest neighbor clustering method. Calculating the distance D between adjacent laser points in S (k):

where ρ (i) and ρ (i +1) are the ith and i +1 th valid points in the laser radar point cloud, D (ρ (i) and ρ (i +1)) are the distance between two adjacent points, and D_thIs a set breakpoint distance threshold;

if D (ρ (i), ρ (i +1)) is greater than D_thMarking rho (i) and rho (i +1) as breakpoints, and marking each type of point cloud after finishing clustering as S_d(k)，1≤d≤N_D，N_DThe quantity of the clustered laser radar point clouds is obtained; then the point cloud S_d(k) The average value of the points in the point cloud is obtained to obtain the central point of each point cloud, then the pose information of the ground winding inspection device at the moment of k-1 is utilized to screen the classes which are segmented by the point cloud, the points which do not meet the requirements are removed, the calculation formula is as follows,wherein d is_LW(k-1) is the Euclidean distance, psi, between the position of the ground winding inspection device in the airplane coordinate system at the time k-1 and the coordinates of the airplane wheel in the airplane coordinate system_LWAnd (k-1) obtaining angle information between the pose of the ground winding inspection device in the airplane coordinate system at the moment k-1 and the coordinates of the wheel in the airplane coordinate system. d_LC(k) Is the Euclidean distance phi from the central point of each type under the machine system to the original point of the machine system at the moment k_LC(k) And (4) the directions of various central points under the machine system at the moment k, and r and gamma are set distance threshold values and angle threshold values. d_LW(k)、ψ_LW(k)、 d_LC(k)、ψ_LC(k) The calculation formula of (a) is as follows:

(1)

(2)

(3)

(4)

wherein the content of the first and second substances,is the coordinate of the center point of the class at the moment k under the machine system;

is the coordinates of the airplane wheel in the airplane coordinate system; x is the number ofⁿ(k-1)、yⁿ(k-1)、ψⁿ(k-1) is the position of the k-1 time flight-winding inspection device under an airplane coordinate system, a plurality of groups of point clouds corresponding to a certain airplane wheel possibly exist after screening by the method, and the screened laser radar point clouds are recorded as laser radar point clouds n₀The number of wheels is indicated and,representing the number of different point clouds corresponding to each wheel.

Calculating the relative distance between the central points of the laser radar point clouds corresponding to different airplane wheels, and comparing the relative distance relation between the airplane wheels:

whereinRepresenting the corresponding wheel n₁The center point of a certain group of laser radar point clouds in the point cloud belongs to the corresponding n₂The euclidean distance between the center points of a certain set of lidar point clouds,

indicating the wheel n₁And airplane wheel n₂The euclidean distance between them, d representing the set threshold.

Screening out a group of laser radar point cloud sets meeting all relative position relations between airplane wheelsAnd combining the points into L (k), wherein the L (k) is the laser radar point cloud of the airplane wheel.

Step S20, in the checking process, carrying out point cloud matching on the laser radar point cloud of the airplane wheel under the coordinate system of the winding checking device and the laser radar point cloud map to obtain a conversion matrix for converting the laser radar point cloud of the airplane wheel to the airplane coordinate system in the coordinate system of the winding checking device;

in the process of the winding inspection, laser radar point clouds of airplane wheels are obtained after screening laser radar points acquired by a winding inspection device, the acquired laser radar point clouds are acquired for a coordinate system based on the winding inspection device, point cloud matching is carried out on the laser radar point clouds of the airplane wheels and a laser radar point cloud map acquired before the winding inspection, and the purpose that the laser radar point clouds taking the winding inspection device as the coordinate system are converted into the laser radar point clouds under the airplane coordinate system is achieved. The coordinate system of the winding machine inspection device can be constructed by taking the center of mass of the winding machine inspection device as an origin, wherein the y axis is forward along the longitudinal axis of the winding machine inspection device, and the x axis is rightward along the longitudinal axis of the winding machine inspection device.

Referring to fig. 3, the step of performing point cloud matching on the acquired laser radar point cloud of the wheel under the coordinate system of the winding inspection device and the laser radar point cloud map to obtain a conversion matrix for converting the laser radar point cloud of the wheel to the coordinate system of the airplane in the coordinate system of the winding inspection device includes:

step S21, when the winding inspection device is at an initial inspection time, acquiring laser radar point cloud of the wheel under a winding inspection device coordinate system at the initial inspection time;

and step S22, performing point cloud matching on the laser radar point cloud of the airplane wheel and the laser radar point cloud map to obtain a conversion matrix for converting the laser radar point cloud of the airplane wheel to the airplane coordinate system in the winding inspection device coordinate system at the initial inspection moment.

Wherein the step of determining the attitude of the winding inspection device in the aircraft coordinate system according to the transformation matrix comprises:

and step S23, if the winding inspection device is at the initial inspection time, determining the first pose of the winding inspection device in the airplane coordinate system at the initial inspection time according to the transformation matrix of the initial inspection time.

In the present embodiment, a pose determination method of confirming an initial inspection timing of a winding inspection apparatus is proposed. That is, when the winding inspection apparatus performs an initial inspection task, the lidar point cloud for acquiring the wheel at the initial inspection time is matched with the point cloud map, which may be specifically understood as setting the lidar point cloud for acquiring the wheel at the initial inspection time as a source point cloud, setting the lidar point cloud map for acquiring the wheel as a target point cloud, and making the original point cloud and the target point cloud substantially coincide by rotation and translation, wherein a transformation matrix R, T from the original point cloud to the target point cloud is obtained. Suppose that the transformation matrix R, T is solved asThe position of the winding inspection device in the plane coordinate system and the course information of the winding inspection device at the initial inspection moment

The first pose of the initial checking time is a passing point of the winding checking device at the initial checking timeThe cloud matching method determines the pose under the airplane coordinate system.

Referring to fig. 4, the step of performing point cloud matching on the laser radar point cloud of the wheel under the winding inspection device coordinate system and the laser radar point cloud map to obtain a conversion matrix for converting the laser radar point cloud of the wheel to the aircraft coordinate system in the winding inspection device coordinate system further includes:

step S24, when the winding machine inspection device is at the non-initial inspection time, acquiring the laser radar point cloud of the wheel under the winding machine inspection device coordinate system at the current time;

step S25, converting the laser radar point cloud according to the pose of the winding inspection in the airplane coordinate system at the last moment to obtain an original laser radar point cloud;

and step S26, performing point cloud matching on the original laser radar point cloud and the laser radar point cloud map to obtain a conversion matrix for converting the laser radar point cloud of the airplane wheel to the airplane coordinate system in the winding inspection device coordinate system at the current moment.

The step of determining the pose of the winding inspection device in an airplane coordinate system according to the transformation matrix comprises the following steps:

and step S27, if the winding inspection device is at the non-initial inspection time, determining a first pose of the winding inspection device at the current time in an airplane coordinate system according to the conversion matrix at the current time.

When the winding inspection device (winding inspection device) is at a non-initial inspection time, the pose of the winding inspection device at the previous time of the current time is acquired, and the pose (x) of the winding inspection device at the time k-1 is acquiredⁿ(k-1),yⁿ(k-1),ψⁿ(k-1)), performing coordinate conversion on the laser radar point cloud L (k) of the airplane wheel processed in the step 2 to obtain a new laser radar point cloud L '(k), and setting the L' (k) as an original point cloud;

note p_iThe ith laser spot (i ═ 1, 2, …, N) of l (k)₀)，N₀P is the number of laser spots in L (k)_iThe ith laser spot (i ═ 1, 2, …) 'L' (k)，N₀)，N₀The number of laser points in L' (k) is obtained by the following conversion relationship:

wherein the content of the first and second substances,and

is p'_iCoordinates under a laser radar rectangular coordinate system,andis p_iAnd coordinates under a laser radar rectangular coordinate system.

And setting a laser radar point cloud map of the airplane wheel, which is acquired by the winding inspection device when the winding inspection task is executed, as a target point cloud. Setting parameters including maximum number of iterations K_sMaximum of sum of mean square errors RMSE_maxThe difference Δ T between two transformation matrices, the maximum distance d between corresponding points_max。

Through a point cloud registration method (such as ICP algorithm), a conversion matrix R, T from the original point cloud to the target point cloud is obtained, and the pose of the orbiting inspection device at the moment k in an airplane coordinate system is assumed to beThen:

so that the pose of the winding inspection device in the airplane coordinate system at the non-initial inspection time (k time) is obtained according to the R, T solution

And step S30, determining the position and posture of the winding inspection device in the airplane coordinate system according to the conversion matrix.

The laser radar point cloud obtained by taking the winding inspection device as a coordinate system is matched with a point cloud map and converted into the point cloud taking the airplane as the coordinate system, so that the pose changes of the winding inspection device at different moments are solved, and the pose of the winding inspection device comprises the position information of an x axis and a y axis of the winding inspection device under the airplane coordinate system and the driving direction of the winding inspection device.

In this embodiment, when the winding inspection device inspects around an airplane, firstly, the winding inspection device runs around the airplane to be inspected for one circle, laser radar point clouds of the airplane wheels at different moments are obtained through a laser scanning device of the winding inspection device, a laser radar point cloud map of the airplane wheels under an airplane coordinate system is established, in the inspection process, the obtained laser radar point clouds of the airplane wheels under the winding inspection device coordinate system are subjected to point cloud matching with the laser radar point cloud map, a conversion matrix of the laser radar point clouds of the airplane wheels converted to the airplane coordinate system under the winding inspection device coordinate system is obtained, and the pose of the winding inspection device under the airplane coordinate system is determined according to the conversion matrix. By the mode, when the position and the pose of the winding inspection device in the winding inspection process are determined, positioning systems such as a GPS (global positioning system) and the like are not needed, so that the problem that when the position and the pose of the winding inspection device are determined by the GPS is avoided, the positioning of the winding inspection device is inaccurate due to the existence of a satellite refused environment is solved, and the effect of improving the positioning accuracy of the winding inspection device in the process of executing the inspection task is achieved.

Referring to fig. 5, fig. 5 is a schematic flowchart of another embodiment of the present application, after the step of determining the first pose of the winding inspection apparatus in the aircraft coordinate system according to the transformation matrix, the method includes:

step S31, acquiring the pose of the winding inspection device in the SLAM coordinate system;

step S32, judging whether the vehicle winding inspection device is at the initial time;

step S33, if the winding inspection device is at the initial inspection time, acquiring a first pose of the initial inspection time, and converting the pose of the winding inspection device at the initial time in the SLAM coordinate system into a pose in an airplane coordinate system;

step S34, if the winding inspection device is at the non-initial inspection time, acquiring the pose of the winding inspection device under the airplane coordinate system at the previous time of the current time, and converting the pose under the SLAM coordinate system at the current time into a second pose under the airplane coordinate system.

Acquiring acquired laser radar original point cloud data (laser radar point cloud not needing to be screened), and resolving to obtain a k-time SLAM (simultaneous localization and mapping) by a method of simultaneously locating and mapping (SLAM) to obtain a position posture of the winding inspection device in an SLAM coordinate systemThe method for determining the pose of the winding inspection device in the airplane coordinate system by means of the SLAM coordinate system is divided into an initial inspection time and a non-initial inspection time, and comprises the following steps:

if the current k moment is the initial inspection moment, reading a first position of the winding inspection device at the initial inspection moment obtained after the midpoint cloud registration in the first embodiment in the plane coordinate system

Obtaining a conversion relation from the SLAM coordinate system to the airplane coordinate system as follows:

wherein

Representing the pose of the winding inspection device obtained by SLAM resolving at the current initial inspection time k in an airplane coordinate system;

if the current time is not the initial checking time, e.g. the current timeWhen the moment is k, reading the pose information (x) of the winding inspection device at the moment k-1 in the airplane coordinate systemⁿ(k-1),yⁿ(k-1),ψⁿ(k-1)), the position of the winding inspection device in the SLAM coordinate system is obtained by SLAM resolving at the time of k-1

And correcting a rotation matrix from the SLAM coordinate system to the airplane coordinate system through the difference value between the poses according to the following equation:solving to obtain;

when k time is obtained, the pose of the winding inspection device obtained by SLAM calculation in the airplane coordinate system

Comprises the following steps:

the embodiment provides a method for obtaining the pose of the winding inspection device in the airplane coordinate system by establishing the SLAM coordinate system. The laser radar point cloud data acquired in the established SLAM coordinate system is original point cloud data, and the pose of the winding inspection device under the SLAM coordinate system is converted into a second pose at the initial inspection time and a second pose at the non-initial inspection time of the winding inspection device under the airplane coordinate system through respectively converting with a first pose at the initial inspection time and a first pose at the non-initial inspection time of the winding inspection device.

Referring to fig. 6, fig. 6 is a diagram of another embodiment of the present application, after the step of determining the first pose of the orbiting inspection device in the aircraft coordinate system according to the transformation matrix, the method further includes:

step S34, judging whether the first position and the second position of the winding inspection device at the current time are accurate according to the data information of an inertial sensor of the winding inspection device and a vehicle-mounted odometer;

step S35, if the attitude is accurate, performing data fusion on the first attitude and the second attitude at the current moment, inertial sensor data and vehicle-mounted odometry data by using extended Kalman filtering to obtain a more accurate attitude of the winding inspection device in an airplane coordinate system;

and step S36, if the attitude of the winding inspection device is inaccurate, acquiring the attitude of the winding inspection device obtained by recursion of the inertial sensor and the vehicle-mounted odometer as the attitude of the winding inspection device at the current moment in an airplane coordinate system.

And judging whether the first position and the second position of the winding inspection device at the current moment are accurate according to the data information of an inertial sensor and a vehicle-mounted odometer of the winding inspection device, and performing data fusion on the position and the attitude of the accurate position and attitude information according to the judgment result to obtain the position and the attitude information of the winding inspection device in an airplane coordinate system.

One-step prediction of mean square error P_k|k-1The calculation formula of (a) is as follows:

where Φ is the state transition matrix, Φ_k,k-1Is the state transition matrix for time k-1 to k,_k-1is the noise matrix of the filter at the time k-1, W_k-1Is the noise matrix of the system at time k-1;

in which M is_4×4，U_4×3，N_3×4All intermediate variables were calculated as follows:

wherein the content of the first and second substances,is a coordinate transformation matrix from a k-1 moment machine system to an airplane coordinate system, are respectivelyThe first, second, and third rows of (a); Δ t is the discrete time of the system; i is an identity matrix;

the noise matrix of the filter is calculated as follows:

noise matrix of a system

Wherein the content of the first and second substances,_wx，_wy，_wzare respectively

The model noise of (1);_ax，_ay，_azare respectively

The model noise of (1);

are respectively

The noise standard deviation of (d);

are respectivelyThe noise standard deviation of (d);

updating the state according to the measurement;

the calculation method of the filter gain equation of the system is as follows:

wherein, K_kIs the filter gain, R, of the system at time k_kIs to measure the noise matrix, H_kIs a measurement matrix;

according to the difference of the current state of the winding inspection device and the reliability of the measurement information, the measurement noise matrix and the measurement matrix are different, and the method specifically comprises the following steps:

a) judging whether the winding inspection device is in the zero-speed state or not according to the feedback provided by the control mechanism, and if the winding inspection device is in the zero-speed state, using the position information and the course information (x) of the winding inspection device at the moment of k-1ⁿ(k-1),yⁿ(k-1),ψⁿ(k-1)) as a measurement, the measurement matrix H (k) and the measurement noise matrix R (k) are respectively:

wherein diag denotes a matrix diagonalization, whereinAre respectively xⁿ(k-1)、 yⁿ(k-1)、ψⁿ(k-1) noise; x is the number ofⁿ(k-1)、yⁿ(k-1)、ψⁿ(k-1) x, y direction coordinates and yaw angle, psi, of the flight inspection device in the aircraft coordinate system at time k-1ⁿ(k-1) is related to the attitude quaternion as follows:

the state estimation equation of the system is calculated as follows:

wherein the content of the first and second substances,

is an estimate of the state quantity at time k,the state variable one-step predicted value from the k-1 moment to the k moment is obtained; z_kThe measured value of the checking device to be wound at the moment k is obtained; z_k＝[xⁿ(k-1) yⁿ(k-1) ψⁿ(k-1)]；

The estimated mean square error equation of the system is:

P_k|k＝(I-K_kH_k)P_k|k-1

wherein, P_k|kThe mean square error is estimated for time k, I is the identity matrix.

b) If the winding machine checking device is not in a zero-speed state at present and the information obtained by the first pose and the second pose is reliable, the information obtained by the first pose, the second pose and the odometer is used as measurement, and a measurement matrix and a measurement noise matrix are respectively as follows:

wherein diag denotes a matrix diagonalization, whereinAre respectively as

The noise of (2) is detected,respectively obtaining x and y direction coordinates and a course angle of the k-time winding inspection device in an airplane coordinate system from a first position at the non-initial inspection time;

are respectively as

The noise of (2) is detected,respectively obtaining x and y direction coordinates and a yaw angle of the flight-winding inspection device at the k moment obtained by the SLAM calculation;

and

are respectively asThe noise of (2) is detected,

the speed of the odometer at the moment k in the x and y directions of the coordinate system of the airplane respectively. The relationship between yaw angle and attitude quaternion is as follows:

the state estimation equation of the system is calculated as follows:

wherein the content of the first and second substances,

is an estimate of the state quantity at time k,the state variable one-step predicted value from the k-1 moment to the k moment is obtained; z_kThe measured value of the inspection device to be wound at the time k is calculated as follows: (ii) a

The estimated mean square error equation of the system is:

P_k|k＝(I-K_kH_k)P_k|k-1

wherein, P_k|kThe mean square error is estimated for time k, I is the identity matrix.

c) If the winding machine checking device is not in a zero-speed state at present, the information obtained by the first position posture is reliable, and the information obtained by the second position posture is unreliable, the information obtained by the first position posture and the odometer is used as measurement, and a measurement matrix and a measurement noise matrix are respectively as follows:

wherein diag denotes a matrix diagonalization, whereinAre respectively as

The noise of (2) is detected,coordinates of the flight-winding inspection device in x and y directions of an airplane coordinate system and a yaw angle at the moment k, which are obtained by the first attitude respectively;andare respectively asThe noise of (2) is reduced to a low level,

the speed of the odometer at the moment k in the x and y directions of the coordinate system of the airplane respectively. The relationship of yaw angle to attitude quaternion is as follows:

the state estimation equation of the system is calculated as follows:

wherein the content of the first and second substances,

is an estimate of the state quantity at time k,is a state variable one from the time k-1 to the time kStep (4) predicting value; z_kThe measured value of the checking device to be wound at the moment k is calculated as follows:

the estimated mean square error equation of the system is:

P_k|k＝(I-K_kH_k)P_k|k-1

wherein, P_k|kThe mean square error is estimated for time k, I is the identity matrix.

d) If the winding machine checking device is not in a zero-speed state at present, the information obtained by the first position posture is unreliable, and the information obtained by the second position posture is reliable, the information obtained by the second position posture and the odometer is used as measurement, and a measurement matrix and a measurement noise matrix are respectively as follows:

wherein diag denotes matrix diagonalization,are respectively as

The noise of (2) is detected,respectively obtaining x-direction coordinates, y-direction coordinates and yaw angles of the flight inspection device at the k moment obtained by SLAM in an aircraft coordinate system;

and

are respectively asThe noise of (2) is detected, the speed of the odometer at the moment k in the x and y directions of the coordinate system of the airplane respectively. The relationship between yaw angle and attitude quaternion is as follows:

the state estimation equation of the system is calculated as follows:

wherein the content of the first and second substances,

is an estimate of the state quantity at time k,

the state variable one-step predicted value from the k-1 moment to the k moment is obtained; z_kThe measured value of the checking device to be wound at the moment k is obtained;

the estimated mean square error equation of the system is:

P_k|k＝(I-K_kH_k)P_k|k-1

wherein, P_k|kThe mean square error is estimated for time k, I is the identity matrix.

e) If the winding machine checking device is not in a zero-speed state at present and the information of the first pose and the second pose is unreliable, the information obtained by the odometer is used as measurement, and a measurement matrix and a measurement noise matrix are respectively as follows:

H(k)＝[0_2×6I_2×20_2×6]

wherein the content of the first and second substances,

andare respectively as

The noise of (2) is detected,the speed of the odometer in the x and y directions of the navigation system, respectively.

The state estimation equation of the system is calculated as follows:

wherein the content of the first and second substances,

is an estimate of the state quantity at time k,the state variable one-step predicted value from the k-1 moment to the k moment is obtained; z_kThe measured value of the checking device to be wound at the moment k is obtained;

the estimated mean square error equation of the system is:

P_k|k＝(I-K_kH_k)P_k|k-1

wherein, P_k|kThe mean square error is estimated for time k, I is the identity matrix.

Judging whether the first position and the second position of the winding inspection device at the current moment are accurate or not, wherein the judging step comprises the following steps of:

in this embodiment, the first position and the second position of the winding inspection device at the current time are respectively compared with the predicted position and the predicted position of the current time, and if the calculated difference is within a preset range, the first position and the second position at the current time are considered to be accurate.

According to the data of the inertial sensor and the vehicle-mounted odometer, whether the first position and the second position obtained by the winding inspection device in the first embodiment and the second embodiment in the plane coordinate system at the initial inspection time and the first position and the second position at the non-initial inspection time are accurate or not is judged, and the method comprises the following steps:

(1) and predicting the attitude, the speed and the position of the device to be tested around the aircraft at the current moment according to the information of the inertial sensor and an extended Kalman filtering algorithm. First, a 14-dimensional state quantity is selected as

q₀、q₁、q₂、q₃Quaternion, x, representing the attitude of the winding inspection deviceⁿ、yⁿRespectively representing the position of the winding inspection device in the x and y directions of the plane coordinate system,representing the speed of the orbiting inspection device in the x and y directions of the aircraft coordinate system,

respectively representing the zero offset of the gyroscope in the x, y and z directions,representing the zero offset of the accelerometer in the x, y, z directions, respectively. The following formulas are adopted for predicting the attitude, the speed and the position of the inspection device to be wound at the current moment:

the attitude quaternion prediction formula is as follows:

wherein, the time k is the current time, and q (k) is [ q ]₀(k),q₁(k),q₂(k),q₃(k)]^TThe attitude quaternion of the winding inspection device at the moment k; q (k-1) ═ Q₀(k-1),q₁(k-1),q₂(k-1),q₃(k-1)]^Tk-1 is a posture quaternion of the moment winding inspection device; superscript T represents the transpose of the matrix; Δ t is the discrete sampling period; Ω (k) is an intermediate variable, and is calculated by the following formula:

the calculation method of (2) is as follows:

whereinIs omega^b(k) Component in x, y, z direction, ω^b(k) The angular speed of the body system of the winding inspection device relative to the plane coordinate system at the moment k is represented under the system;

(2) the position prediction formula is:

wherein x isⁿ(k)、yⁿ(k) The position of the winding inspection device in the plane coordinate system at the moment k; x is the number ofⁿ(k-1)、 yⁿAnd (k-1) is the position of the orbiting checking device in the airplane coordinate system at the moment k-1.

The component of the projection of the linear velocity of the body system of the winding inspection device relative to the airplane coordinate system in the X-axis direction and the Y-axis direction at the moment of k-1;

(3)

calculated by the following formula:

whereinIs the projection of the acceleration of the body system of the flight-winding inspection device relative to the airplane coordinate system at the moment k in the airplane coordinate system,

the projection of the acceleration (except the gravity acceleration) of the body system of the winding inspection device relative to the plane coordinate system at the moment k on the plane system.

The attitude matrix is obtained from an airframe to an airplane coordinate system, and the calculation formula is as follows:

(4) the prediction formula of the speed is as follows:

reading the pose resolved at the non-initial inspection time (k time)And predicting to obtain the pose (x)ⁿ(k),yⁿ(k),ψⁿ(k) Compare, calculate the difference between:

wherein, Δ x, Δ y, Δ ψ are set threshold values, and if the above conditions are satisfied, the pose obtained in step 4 is considered to be reliable;

then, the pose of the winding inspection device at the current moment in the SLAM coordinate system is obtainedAnd predicting to obtain the pose (x)ⁿ(k),yⁿ(k),ψⁿ(k) Compare, calculate the difference between:

and if the conditions are met, the pose obtained through SLAM is considered to be reliable.

In this embodiment, the first pose and the second pose at the initial inspection time, and the first pose and the second pose at the non-initial inspection time are determined by obtaining the odometer information of the winding inspection device, so as to obtain a more accurate pose of the winding inspection device in the aircraft coordinate system.

Furthermore, the present application provides a computer-readable storage medium storing a positioning program of a winding inspection apparatus, which when executed by a processor implements the steps of the positioning method of the winding inspection apparatus described above.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application 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 the like) having computer-usable program code embodied therein.

The present application has been described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. 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.

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.

It should be noted that in the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The application can be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by one and the same item of hardware. The usage of the words first, second and third, etcetera do not indicate any ordering. These words may be interpreted as names.

While alternative embodiments of the present application have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following appended claims be interpreted as including alternative embodiments and all such alterations and modifications as fall within the scope of the application.

Obviously, various modifications and alterations to this application will become apparent to those skilled in the art without departing from the invention

With clear spirit and scope. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include such modifications and variations.