Sensor system for a vehicle and method for determining a threat assessment

文档序号：1786002 发布日期：2019-12-06 浏览：15次中文

阅读说明：本技术 用于车辆的传感器系统和用于确定威胁评估的方法 (Sensor system for a vehicle and method for determining a threat assessment ) 是由 M·霍拉 C·莱茵费尔德于 2017-12-22 设计创作，主要内容包括：教导了用于车辆的传感器系统和用于分析来自传感器系统的数据的方法。传感器系统包括安装在车辆的一部分上的至少两个雷达传感器阵列和从至少两个雷达传感器阵列接收数据的分析系统。分析系统适于由数据生成威胁评估。雷达传感器阵列可以安装在其他组件中。(Sensor systems for vehicles and methods for analyzing data from sensor systems are taught. The sensor system includes at least two radar sensor arrays mounted on a portion of the vehicle and an analysis system that receives data from the at least two radar sensor arrays. The analysis system is adapted to generate a threat assessment from the data. The radar sensor array may be mounted in other assemblies.)

1. A sensor system (20) for a vehicle (10), comprising:

At least one radar sensor array (40) mounted on a portion (12) of the vehicle (10);

An analysis system (50) receiving radar data from the at least two radar sensor arrays (40), wherein the analysis system (50) comprises a processor (52) and a stored data set (54), and wherein the processor (52) is adapted to generate a threat assessment from the received radar data and the stored data set (54).

2. The sensor system (20) of claim 1, further comprising at least one image sensor (30) mounted on the vehicle (10).

3. The sensor system (20) of claim 1 or 2, wherein the at least one radar sensor array (40) comprises a plurality of antenna elements (42).

4. The sensor system (20) of claim 2, wherein the plurality of radar elements (42) are mounted in a strip.

5. Sensor system (20) according to any of the preceding claims, wherein the at least two radar sensor arrays (40) are further at least partially mounted on a side portion (14) of the vehicle.

6. The sensor system (20) of any of claims 2-5, wherein the at least one image sensor (30) is mounted on a roof (16) of the vehicle (12).

7. The sensor system (20) of any one of the preceding claims, wherein the processor (52) is further adapted to update the stored data set (54).

8. A method for analyzing a plurality of sensor data to generate a threat assessment from one or more objects (60), wherein the sensor data includes at least radar data, and the method comprises:

-receive the radar data from at least one radar sensor array (40);

-processing the radar data using a processor (52) and a stored data set (54) to identify the one or more objects (60); and

Generating the threat assessment from the one or more objects (60) based on the processed radar data.

9. The method of claim 8, further comprising receiving image data from at least one image sensor (30) and additionally using the image data to generate the threat assessment.

10. The method of claim 8 or 9, further comprising updating the data set (54).

11. The method of claim 10, wherein the updating comprises: known objects are identified and the received sensor data is compared to expected values in the data set (54).

12. The method of claim 11, wherein the identifying comprises identifying at least one of a horizontal object or a vertical object from the image data.

13. A vehicle comprising a sensor system according to at least one of claims 1 to 6.

14. The vehicle of claim 12, further comprising a vehicle control system for receiving the generated threat assessment and initiating a vehicle action in response to the generated threat assessment.

15. A sensor array includes a plurality of radar antennas arranged in a strip on a substrate and mountable on a vehicle body.

Technical Field

The invention comprises a sensor system for a vehicle and a vehicle equipped with such a sensor system. The present invention also provides a method for analyzing a plurality of sensor data and thereby determining a threat assessment using a sensor system.

Background

sensor systems for vehicles are known in the art. These are used in particular in autonomous or semi-autonomous vehicles and in driver assistance systems. The sensor system includes one or more sensors located on the body (chassis, dashboard, bumper, etc.) of the vehicle and can determine objects in the vicinity of the vehicle. The sensor data sent by the sensor may be processed autonomously by the sensor or used by the unit to generate a threat assessment (assessment threshold), for example whether a collision with another vehicle, human or animal is possible. Threat assessment may be used to slow or stop the car altogether or to automatically maneuver the vehicle away from the identified threat assessment.

for example, U.S. patent 6,151,539 (Volkswagen) teaches an autonomous vehicle and a method for controlling an autonomous vehicle. The autonomous vehicle includes a sensor array including at least one distance sensor for detecting an object and at least one distance sensor for detecting a condition characteristic of the route.

A multisensor system is known from us patent 7,102,496 (Yazaki North America) which discloses a sensor system comprising a plurality of external sensors. The system uses a threat assessment subsystem to integrate data from multiple external sensors to generate a threat assessment, such as but not limited to a possible collision.

Another example of an autonomous vehicle with a sensor is known from us 5,307,419 (Honda), which discloses at least one image pickup unit picking up an image of a moving road or a moving body. The image processing unit processes data from the image pickup unit and may control the autonomous vehicle.

U.S. patent No. 5,467,072 (Piccard Enterprises) teaches a phased array based radar for vehicle safety warning systems for collision avoidance. A vehicle safety warning system includes a phased array based radar, a control processor and a warning system that also warns drivers of equipped vehicles and other unarmed automobiles that are involved in unsafe driving conditions. Phased array radars include flexible antenna arrays that can be conformally (conformally) mounted on existing automobiles without reducing their design curvature. In one embodiment described in this patent, a pair of phased array radar antennas may be oriented toward opposite sides of an equipped automobile to provide warning surveillance of vehicles approaching the equipped automobile laterally from the sides. In another embodiment, the phased array radar antenna is directed toward the rear of the equipped car to provide warning surveillance of vehicles following the equipped car too close and for warning of unsafe lane changes.

A known problem with radar-based vehicle safety warning systems using conformally mounted phased array radars, such as disclosed in US'072, is that the radiation emitted from the array depends on most of the location of the radar, as well as the paint coating.

Disclosure of Invention

In this document a sensor system for a vehicle is taught. The sensor system includes one or more radar sensor arrays mounted on a portion of the vehicle and an analysis system that receives data from the radar sensor arrays. The analysis system includes a processor and a stored data set. The analysis system is adapted to receive radar data from the array of radar sensors and generate a threat assessment from the received radar data and the data set. One or more radar sensor arrays may be mounted in or on a component of the vehicle body. The radar sensor array may be mounted around the entire body to provide up to 360 ° of ambient sensing coverage.

In another aspect, at least one image sensor is additionally mounted on the vehicle. The image sensor may provide further information regarding the evaluation of potential threats as well as improve the calibration of the radar sensor array.

The at least one radar sensor array includes a plurality of radar elements having a plurality of antenna elements. This improves the sensitivity of detection and increases the aperture and provides redundancy if one of the radar elements or the antenna element fails. The plurality of radar elements are mounted in a strip or matrix arrangement.

This document also describes a method for analyzing a plurality of sensor data to generate a threat assessment. The method includes receiving sensor data from at least one radar sensor array and processing the radar data using a processor and a stored data set to identify one or more objects. A threat assessment is then generated based on the processed radar data.

The method may further include receiving image data from at least one image sensor and additionally using the image data to generate a threat assessment, or calibrating the radar data by identifying horizontal and vertical references.

detailed description of the drawings

FIG. 1 illustrates a vehicle equipped with a sensor system according to one aspect of the present invention.

Fig. 2 shows an example of an array of radar sensors incorporated around a windscreen.

Fig. 3A to 3C show examples of radar sensor arrays incorporated into headlights.

Fig. 4A and 4B show a sensor array having a plurality of radar elements and a plurality of antenna elements adapted to be mounted on a vehicle body.

FIG. 5A illustrates a calibration system for a vehicle using an object.

FIG. 5B shows a calibration system for a moving vehicle.

FIG. 6 illustrates a method for processing data from a sensor system to identify threats.

Detailed description of the invention

FIG. 1 illustrates a vehicle 10 having a sensor system 20 in accordance with an aspect of the present description. The vehicle has a top position 14, which corresponds substantially to the roof of the vehicle 10, a windscreen or windscreen 11, and a front portion 12, which in the figure corresponds substantially to the bonnet of the vehicle 10. It should be understood that the vehicle 10 shown in fig. 1 illustrates a typical automobile or motor vehicle (e.g., a salon), but this is merely illustrative of the present invention. Vehicle 10 may be, but is not limited to, a pick-up truck, a bus, a heavy truck, an articulated truck, or a motorcycle. It is also possible that the sensor system 20 may be used on a rail, a guided bus, a tram or a trolley, and that the sensor system 20 is not limited to use on a road vehicle.

The illustrated sensor system 20 has, in one aspect, at least one image sensor 30 mounted at the roof location 14 on the vehicle 10, although this location of the image sensor 30 is not a limitation of the present invention.

the sensor system has at least one radar sensor array 40, which in this fig. 1 is mounted on the front portion 12 of the vehicle 10. In fig. 1, two radar sensor arrays 40 are seen mounted on each side of the front portion 12 or behind the bumper or fender 13 in an arc around the side of the vehicle 10. This curvature around the side of the vehicle 10 enables the two radar sensor arrays 40 to transmit radar signals in the form of radio waves not only in the forward direction of travel of the vehicle 10, but also at the side of the vehicle 10. The two radar sensors 40 are mounted together in such a way that the synchronization enables the two radar sensors 40 to effectively have a large aperture.

In one aspect of the sensor system 20, the radar sensor array 40 is conformally mounted to the surface of the vehicle 10. This enables the transmitted radar signal to be transmitted more strongly and also eliminates the risk of attenuation of the received radar signal, since components such as fenders/bumpers are located in front of the radar sensor array 40. Thus enhancing the receive sensitivity of the radar sensor array 40. In another aspect, the radar sensor array 40 is structurally integrated into the chassis of the vehicle 10.

Two or more radar sensors may also be additionally mounted on the rear portion 16 of the vehicle 10 to transmit radar signals behind the vehicle 10. For example, in fig. 2, additional radar sensors may be mounted around the windshield 11. Fig. 2 shows a radar sensor 40a located on the left and right side of the windscreen 11 and another radar sensor 40b located on top of the windscreen 11. The radar sensor 40a may be vertically mounted or tilted. It is also possible to incorporate the radar sensor 40c in the headlight 18. Fig. 3A shows two radar sensors 40c incorporated into the headlight 18. Fig. 3B shows three radar sensors 40C incorporated into the headlight 18, and fig. 3C shows a circular headlight 18, such as that used on a motorcycle, having a plurality of radar sensors 40d mounted around the circumference of the headlight 18. The radar sensor array 40 may be injection molded into the part or applied to the exterior of, for example, a vehicle body part using an adhesive. It should be understood that the number of radar sensor arrays 40 is not limiting to the invention, and that the invention may actually work with a single radar sensor array 40.

The two radar sensor arrays 40 are arranged as a plurality of radar elements 42 having a plurality of antenna elements, for example antennas having receivers and transmitters arranged in a strip-like manner on a flexible substrate, as shown in fig. 4. Fig. 4A shows a one-dimensional radar sensor array 40, but it is understood that the radar sensor array 40 may be a two-dimensional array, as shown in fig. 4B. The flexible substrate enables integration of the radar sensor array 40 into the front portion 12 of the vehicle 10. Multiple radar elements means that redundancy is built into the system. If any of the plurality of radar elements fails, the remaining radar elements may still function. The failed radar element may be replaced during a visit to a service shop by the vehicle 10. The radar sensor array 40 may have a self-heating function to melt snow or ice on the radar sensor array 40, which may distort signals.

Multiple radar elements are calibrated by example cross-radiation and sensing. This is a mode of operation in which one radar element in the radar sensor array 40 radiates and the other radar elements listen and are calibrated accordingly to calculate manufacturing tolerances and alignment etc. on the body 10. The calibration may be repeated periodically to compensate for aging and failure of one or more radar elements. The calibration is based on the assumption of known or long-term observed objects, such as, but not limited to, landmarks (e.g., guardrails, tunnels, or bridges), as will be described in more detail below.

The vehicle has an analysis system 50 that is connected to all of the radar sensor arrays 40 and the image sensor 30 by wire or wirelessly, and receives image data from the image sensor 30 and radar data from the radar sensor array 40. The analysis system 50 has a processor 52 for processing the radar data and the image data. The analysis system 50 also has a memory for storing a data set 54, the data set 54 being used to calibrate the radar data and the image data. The values in the data set 54 may be pre-stored and then later adjusted during the calibration step, as described below.

It should be understood that there is a slight delay between the transmission of data from the radar sensor array 40 to the analysis system 50, and that this slight delay will depend on the length of the line or distance from the analysis system 50 to transmit or receive one of the radar sensor arrays 40. This delay needs to be taken into account when analyzing the data. The analysis system 50 is scalable and provides an interface for other sensors, if desired. The analysis system 50 is adapted to generate a threat assessment from sensor data received from the radar sensor array 40 and the image sensor 30 (if present) using the processor 52. It should be understood that the analysis system 50 may be connected to additional sensors not shown in the figures. The analysis system 50 may process data from the radar sensor array 40 using deep learning techniques to predict performance.

The analysis system 50 may include a master oscillator 55 or clock to synchronize all of the radar sensors 40 in the vehicle 10. The master oscillator 55 may also be used to calculate the small delays between the radar sensor array 40, the image sensor 30 and the analysis system 50. The signals received by the radar sensor array 40 may be provided with accurate time stamps for later processing by the analysis system 50.

Existing vehicles can also be retrofitted with wireless connections to enable them to use the system. The analysis system 50 may also be mounted on a smartphone that is wirelessly connected to the retrofitted radar sensor array 40, image sensor 30, and other sensors.

The radar elements in the radar sensor array 40 operate as is known in the art. The radar element generates a radar signal in the form of a radio wave at a specified frequency. The radio waves may strike objects in front of or to the side of the vehicle 10 and then be reflected. The detector detects the reflected radio wave as one of the radar elements, and transmits data generated from the detection to the analysis system 50. The radar sensor arrays 40 may further have their own processors for pre-processing radar data from the radar sensor arrays 40.

The radar sensor arrays 40 may include a beamforming process to adapt the radar sensor data to the location and position of the radar sensors on the vehicle 10 by adjusting parameters (e.g., delay, phase shift, and amplitude) of the radar signals to or from the radar sensors 40 and ensuring that the transmitted and reflected radar signals between adjacent radar sensor arrays 40 on the same strip and on different sensor arrays are coherent. The beamforming process enables the radar sensor array 40 to focus its radar beam on any potential or assessed threat or other object. The beamforming process also enables suppression of side lobes (side lobes) or optimization of the beam pattern of the radar signal that might otherwise generate false positives from the sensor data, such as non-existent threats. Interference cancellation and beamforming may also be used to "zoom in" on the object.

The calibration process will now be described with reference to fig. 5A. Fig. 5A shows a vehicle 10 having two side or corner mounted radar sensor arrays 40. The object 60 is located at a distance (x, y) from the vehicle 10. In a first step, one or both of the radar sensor arrays 40 transmit radar signals Tx1 and Tx2, which are Rx1, Rx2 reflected by the object 60, and then are received by one or both of the radar sensor arrays 50. The received signals Rx1, Rx2 are sent to the analysis system 50. The location and distance (x, y) from the object 60 are precisely known, so the analysis system 50 can determine the coefficients needed for the beamforming process to adapt to the antenna pattern, thereby enabling the object 60 to be accurately identified.

The calibration process may be repeated several times for different objects 60 at different locations to generate individual data sets 54 of the vehicle 10 relating to different objects 60. The individual data set 54 is stored in a memory in the analysis system 50.

Since only two radar sensor arrays 40 are shown, the aspect shown in fig. 5A is simplified. In practice, there will be a plurality of radar sensor arrays 40, so the aperture for sensing is much larger than that provided by known devices. For example, if the radar sensor array 40 is provided such that the radar sensor array 40 is positioned substantially completely around the vehicle 10, a 360 ° field of view is effectively obtained.

The analysis system 50 uses this data to generate a so-called threat assessment. Threat assessment is a threat determined or assessed by the analysis system 50 and is, for example, indicative of a possible collision with a stationary or moving object.

One problem with radar sensor arrays 40 known in the art is that they are sensitive to changes in their position on the body of the vehicle 10 and to changes in performance due to aging. The system and method of this document enables dynamic changes in calibration.

Now assume that the radar sensor array 40 on the bumper is moved because the vehicle has been in an accident or has been hit. A change in the position of the radar sensor array 50 would mean that the threat assessment could be misidentified or mislocated. The analysis system 50 uses data from the image sensor 30 to calibrate or cross-check data from the radar sensor array 40. The image sensor 30 may, for example, view a horizontal object and compare the viewed horizontal object to a horizontal object calculated from radar data from the radar sensor array 40. The image sensor 30 is also able to determine a threat assessment independently of the radar sensor array 40 and use its determination for rationality calibration, or to correct for any errors in the radar sensor array 40. In inclement weather, such as rain or fog, the image sensor 30 may not operate particularly reliably. The analysis system 50 uses the radar data from the radar sensor array 40 and previously calculated correction or correlation factors to determine a threat assessment.

dynamic changes in calibration may be made by making assumptions about the objects 60 (e.g., landmarks) detected by the analysis system 50. Such as shown in fig. 5B, which shows a landmark as a guardrail 70 along one side of a highway on which the vehicle is traveling. Fig. 5B also shows the vehicle 10 about to enter the tunnel 80 or pass under the bridge 80, the bridge 80 being another type of landmark.

The guard rails 70 are typically of a known form and these will reflect radar signals from the radar sensor array 40 in a known manner. The reflected signals from the radar sensor array 40 are analyzed by the analysis system 50 and compared to expected values. If the expected values deviate from the values received from the radar sensor array 40 by a small amount, the data set 54 may be corrected to account for these deviations, which may be due to aging and/or deformation of the vehicle 10. Similarly, the structure of the bridge or tunnel 80 will be known (in this illustrated case, two vertical sides and one horizontal top), and the reflected radar signals can be used to make any corrections to the data set 54.

It will be appreciated that the form of the guard rail 70 and the shape of the entrance or bridge 80 of the tunnel 80 will depend on their location. Based on a GPS or Galileo (Galileo) system, the vehicle 10 may be provided with accurate position sensors, and the analysis system 50 may use the positions to determine the expected form of the guard rail, tunnel entrance or bridge shape.

In another aspect of the invention, data from the image sensor 60 may be used to identify landmarks and/or provide other data for calibrating the radar sensor array 40.

It should be appreciated that if the dynamic calibration indicates large deviations, these deviations may be erroneous and incorrect. Such large deviations will not be used to change the values in the data set 54. The calibration system may then warn that the analysis system 50 is not working properly or ignore significant deviations.

FIG. 6 illustrates a method for determining a threat assessment. It should be understood that this example uses only the image sensor 30 (if present) and the radar sensor array 40 as shown in fig. 1, but the principles may be applied to processing data from other sensors mounted on the vehicle 10.

In a first step 600, the radar sensor array 40 transmits radar signals over an appropriate coverage area. It should be understood that different ones of the radar sensor arrays 40 are adaptive and may have different coverage areas, which may dynamically adapt to a desired field of view. These different coverage areas will, but need not, overlap each other. For example, the radar sensor array 40 on the left side of the vehicle 10 in FIG. 1 would cover both the front and left side views of the vehicle 10. The radar sensor array 40 on the right side will also cover the front side field of view (with some overlap), as well as the right side field of view (without overlap with the left side radar sensor array).

The radar signal may be scanned over a coverage area. In urban areas, it is preferable to scan coverage areas near the vehicle 10 more frequently than more distant coverage areas because, for example, there is a greater risk of collision from nearby objects moving into the path of the moving vehicle. More distant objects are more likely to leave the path of the moving vehicle within the available time, and thus the risk is reduced.

On motorways or motorways (highways) with restricted access, the opposite may be true. Due to the speed of movement of the vehicle 10, there is a greater risk of collision with objects located further away. Furthermore, slow moving objects are unlikely to be present on such highways.

In step 610, any reflected radar signals from one or more objects 60 are detected. The analysis system 50 may also receive image data from at least one image sensor 30 (if present) in step 620. In step 640, the analysis system 50 may use the radar data from the reflected radar signals and the image data (if present) to identify a feature such as the object 60, and in step 650, the analysis system uses the radar data 50 to identify the location of the object 50. This is done by comparing the radar data to the data set 54. The position of the object 60 will be found by identifying the main lobe (main lobe) of the reflected radar signal. Since there will be radar data from more than one radar sensor array 40, a triangulation process may be performed to identify the exact location of the object 60. Other information in the radar data will enable identification of the type of object 60.

In step 660, a threat assessment is generated based on the radar data. Any moving object 60 may be detected by continuously monitoring the position of the moving object 60 and/or by evaluating the doppler signal (if available) and making assumptions about the movement of the object 60 to avoid collisions.

The analysis system 50 may be connected to a vehicle control system 58, which vehicle control system 58 may override the actions of the driver and thus avoid a collision if necessary.

Reference numerals

10 vehicle

11 windscreen or windscreen

12 front part

13 Bumpers or fenders

14 top position

16 rear part

18 head lamp

20 sensor system

30 image sensor

40 radar sensor

50 analysis system

55 master oscillator

60 objects.