Error dynamic compensation system and method based on multiple millimeter wave radars

Abstract

The invention provides an error dynamic compensation system and method based on multiple millimeter-wave radars. The method comprises the following steps: step 1, a data processing unit sends a trigger acquisition signal to each millimeter-wave radar; 2, the millimeter-wave radar sends target detection data and state information of the millimeter-wave radar to a data processing unit; 3, the track generation module writes the rough transformation parameters into an internal reference file; step 4, the parameter system provides the internal reference file for each millimeter wave radar; step 5, obtaining target information subjected to rough transformation; 6, static targets of the target information are filtered, dynamic targets are numbered and tracked, and whether the targets are new targets or not is judged according to the numbers; step 7, if the target is not a new target, storing the tracking trajectory; step 8, matching the tracking trajectory with the adjacent trajectory; and 9, taking the coordinate transformation matrixes of the angular millimeter wave radar and the corresponding forward and backward millimeter wave radars as update parameters, and writing the update parameters into an external parameter file.

Description

Technical Field

[0001] The present application relates to the field of intelligent driving technology, and in particular to an error dynamic compensation system and method based on multi-millimeter-wave radar. Background Art

[0002] Millimeter-wave radar has the characteristics of accurately measuring the distance, speed, angle and other state information of the target object, and can provide vehicles with real-time environmental perception capabilities. Therefore, in the rapid development of autonomous driving and assisted driving, millimeter-wave radar has gradually become one of the indispensable sensors. At the same time, based on its large field of view, it can greatly reduce the blind spot with the same number of sensors. In autonomous driving, the higher the accuracy of the detected target, the lower the risk of autonomous driving and the higher the smoothness of vehicle operation. Therefore, multi-millimeter-wave radar data fusion and fusion accuracy have become urgent problems to be solved. The existing technical solution is based on laser radar. By obtaining the point cloud data of laser radar and multiple millimeter-wave radars, and then matching the point clouds, the affine matrix between laser radar and millimeter-wave radar is obtained, and the coordinate transformation between multiple millimeter-wave radars and laser radar is obtained by analogy. However, the number of millimeter-wave radar point clouds is small, and point cloud matching is more dependent on the amount of data, so the accuracy cannot be guaranteed. Another existing technology constructs a track list by obtaining the front and back frame data of the two radar tracks for fusion, but this method will produce redundant targets, and the fusion of targets with different centers of gravity is too rough. Summary of the invention

[0003] In view of this, the present invention provides an error dynamic compensation system and method based on multiple millimeter-wave radars to solve the technical problems in the prior art such as the small number of millimeter-wave radar point clouds, the inability to ensure accuracy, the appearance of redundant targets in data fusion, and the overly rough fusion of targets with different centers of gravity.

[0004] The present invention provides an error dynamic compensation system based on multiple millimeter-wave radars, which is applied to intelligent driving vehicles. The system comprises: a millimeter-wave radar, which is arranged on the vehicle, and comprises a forward millimeter-wave radar, a backward millimeter-wave radar and an angular millimeter-wave radar. When installed, the scanning areas of the forward millimeter-wave radar, the backward millimeter-wave radar and the angular millimeter-wave radar overlap, and the data processing unit is used to send target detection data and its own state information to a data processing unit after receiving a trigger acquisition signal; the data processing unit is connected to the multiple millimeter-wave radars, and is used to receive the target detection data and its own state information of the millimeter-wave radar, and send a trigger acquisition signal and vehicle body information to each millimeter-wave radar; a parameter system is connected to the multiple millimeter-wave radars, and is used to provide an internal reference file to each millimeter-wave radar and save an external reference file; a trajectory generation module is connected to the data processing unit and the parameter system, and is used to write a coarse transformation parameter into the internal reference file, and write the target detection data into the internal reference file. The target information is obtained by transforming the external reference file, and the static targets are filtered according to the target information. The dynamic targets are numbered and tracked, and it is determined whether they are new targets according to the number. If not, the tracking trajectory is saved. When the number of points in the trajectory reaches a preset threshold, the saved tracking trajectory is sent to the trajectory matching module; the trajectory matching module is connected to the trajectory generation module, and is used to search for adjacent trajectories in the forward or backward millimeter-wave radar scanning list after receiving the tracking trajectory, and match the tracking trajectory of the front corner millimeter-wave radar with the adjacent trajectory in the forward millimeter-wave radar scanning list, and match the tracking trajectory of the rear corner millimeter-wave radar with the adjacent trajectory in the backward millimeter-wave radar scanning list. When the matching degree exceeds the preset value, the coordinate transformation matrix of the corner millimeter-wave radar and the corresponding front and backward millimeter-wave radars is used as an update parameter, and the update parameter is written into the external reference file to realize dynamic compensation of millimeter-wave radar errors.

[0005] Furthermore, the data processing unit is also used to remove error frames in the target detection data.

[0006] Furthermore, the data processing unit is also used to send time synchronization data to each millimeter-wave radar to ensure that the target detection data of each millimeter-wave radar is stored in synchronization.

[0007] Furthermore, the vehicle body information includes gear position, speed, yaw angle, front wheel turning angle, and wheel speed.

[0008] Furthermore, the internal parameter file includes a lateral offset, a longitudinal offset, and an angular offset; the external parameter file includes a translation matrix T and a rotation matrix R.

[0009] Furthermore, the coarse transformation parameters are initial parameters obtained by measuring with a tape measure and an angle measuring instrument.

[0010] The present invention also provides a method for dynamic error compensation based on multiple millimeter-wave radars, the method comprising: step 1, a data processing unit sends a trigger acquisition signal to each millimeter-wave radar; step 2, after the millimeter-wave radar receives the trigger acquisition signal, it sends the target detection data and its own state information to the data processing unit; step 3, the trajectory generation module writes the coarse transformation parameters into an internal reference file; step 4, the parameter system provides the internal reference file to each millimeter-wave radar according to the state information of the millimeter-wave radar to adjust the internal reference of each millimeter-wave radar; step 5, the trajectory generation module transforms the target detection data through the external reference file to obtain the target information after the coarse transformation; step 6, filtering the static target of the target information, and The dynamic targets are numbered and tracked, and whether they are new targets is determined based on the number; step 7, if it is not a new target, the tracking trajectory is saved, and when the number of points in the trajectory reaches a preset threshold, the saved tracking trajectory is sent to the trajectory matching module; step 8, the trajectory matching module matches the tracking trajectory of the front corner millimeter-wave radar with the adjacent trajectory in the forward millimeter-wave radar scanning list, and matches the tracking trajectory of the rear corner millimeter-wave radar with the adjacent trajectory in the backward millimeter-wave radar scanning list; step 9, when the matching degree exceeds the preset value, the coordinate transformation matrix of the front corner millimeter-wave radar and the corresponding front and rear millimeter-wave radars is used as an update parameter, and the update parameter is written into the external reference file to realize the dynamic compensation of the millimeter-wave radar error.

[0011] Furthermore, the step 7 also includes: if it is a new target, go to step 5.

[0012] Furthermore, the step 9 also includes: when the matching degree does not exceed a preset value, go to step 5.

[0013] Furthermore, the system also includes: Step 10, after updating the external reference file, go to Step 5.

[0014] The present invention provides a system and method for dynamic error compensation based on multiple millimeter wave radars. The technical solution transforms the position and speed of target detection data of multiple millimeter wave radars according to the tracking trajectory of dynamic targets, and then transforms and fuses them for use by downstream modules to achieve dynamic compensation. The technical solution is mainly used to solve the technical problems of the existing technology, such as the small number of millimeter wave radar point clouds, the inability to ensure accuracy, the appearance of redundant targets in data fusion, and the overly rough fusion of targets with different centers of gravity. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the layout of a millimeter wave radar provided by the present invention; Figure 2 It is a schematic flow chart of a method for dynamic error compensation based on multi-millimeter-wave radar provided by the present invention; Figure 3 It is a schematic diagram of the trajectory generation process provided by the present invention. DETAILED DESCRIPTION

[0016] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0017] Device Item Example: The present invention provides an error dynamic compensation system based on multiple millimeter-wave radars, which is applied to intelligent driving vehicles. The system comprises a millimeter-wave radar, a data processing unit, a parameter system, a trajectory generation module, and a trajectory matching module.

[0018] like Figure 1 As shown, the millimeter-wave radar is arranged on the vehicle, including a forward millimeter-wave radar 1, a rearward millimeter-wave radar 4 and a corner millimeter-wave radar (indicated by numbers 2 and 3 in the figure). When installed, the scanning areas of the forward and rearward millimeter-wave radars and the corner millimeter-wave radar 2 overlap, and are used to send target detection data and their own status information to the data processing unit after receiving the trigger acquisition signal. Figure 1 The common layout of millimeter-wave radar is shown in the figure. In practical applications, it can be adjusted or increased or decreased according to actual conditions.

[0019] The data processing unit is connected to multiple millimeter-wave radars, and is used to receive the target detection data and its own status information of the millimeter-wave radar, and send the trigger acquisition signal and the vehicle body information to each millimeter-wave radar; the data processing unit is also used to remove the error frames in the target detection data. The vehicle body information includes gear position, speed, yaw angle, front wheel angle, and wheel speed. The data processing unit is also used to send time synchronization data to each millimeter-wave radar to ensure that the target detection data of each millimeter-wave radar is saved in time synchronization. In addition, the data processing unit exchanges data with the millimeter-wave radar through CAN (Controller Area Network, an internationally standardized serial communication protocol).

[0020] The parameter system is connected to multiple millimeter-wave radars and is used to provide internal parameter files to each millimeter-wave radar and save external parameter files; the internal parameter files include lateral offset, longitudinal offset, and angular offset; the external parameter files include translation matrix T and rotation matrix R.

[0021] The trajectory generation module is connected to the data processing unit and the parameter system, and is used to write the coarse transformation parameters into the internal reference file, transform the target detection data through the external reference file, obtain the target information, filter the static targets according to the target information, number and track the dynamic targets, and judge whether it is a new target according to the number. If not, save the tracking trajectory, and send the saved tracking trajectory to the trajectory matching module when the number of points in the trajectory reaches a preset threshold. The coarse transformation parameters are initial parameters set by using a tape measure and an angle measuring instrument.

[0022] The trajectory matching module is connected to the trajectory generation module. After receiving the tracking trajectory, it searches for the adjacent trajectory in the forward or backward millimeter-wave radar scanning list, matches the tracking trajectory of the front corner millimeter-wave radar 2 with the adjacent trajectory in the scanning list of the forward millimeter-wave radar 1, and matches the tracking trajectory of the rear corner millimeter-wave radar 3 with the adjacent trajectory in the scanning list of the backward millimeter-wave radar 4. When the matching degree exceeds the preset value, the coordinate transformation matrix of the front corner millimeter-wave radar and the corresponding front and backward millimeter-wave radars is used as the update parameter, and the update parameter is written into the external reference file to realize the dynamic compensation of the millimeter-wave radar through the coordinate change.

[0023] The present invention provides a system and method for dynamic error compensation based on multiple millimeter wave radars. The technical solution transforms the position and speed of target detection data of multiple millimeter wave radars according to the tracking trajectory of dynamic targets, and uses the transformed and fused data for downstream modules to achieve dynamic compensation. The technical solution is mainly used to solve the technical problems of the existing technology, such as the small number of millimeter wave radar point clouds, the inability to ensure accuracy, the appearance of redundant targets during data fusion, and the overly rough fusion of targets with different centers of gravity.

[0024] Method Item Example: like Figure 2 As shown, the present invention provides an error dynamic compensation method based on multi-millimeter wave radar, and the method steps are as follows.

[0025] Step 1: The data processing unit sends a trigger acquisition signal to each millimeter wave radar; The data processing unit sends the trigger acquisition signal and time synchronization data at the same time to ensure that the target detection data of each millimeter wave radar is saved in synchronization.

[0026] Step 2: After receiving the trigger acquisition signal, the millimeter wave radar sends the target detection data and its own status information to the data processing unit; Step 3, the trajectory generation module writes the coarse transformation parameters into the internal reference file; The internal reference file is provided by the parameter system according to the requirements of the millimeter wave radar, generally for lateral offset, longitudinal offset, and angular offset. The internal reference file of the millimeter wave radar is an important document to ensure the normal, efficient, and safe operation of the system, and contains aspects such as system configuration, calibration, signal processing, diagnosis, application scenario configuration, and safety information. The coarse transformation parameters are the initial parameters set by using a tape measure and an angle measuring instrument.

[0027] Step 4: The parameter system provides the internal parameter file to each millimeter-wave radar according to the status information of the millimeter-wave radar to adjust the internal parameters of each millimeter-wave radar; Since the internal parameters of the millimeter-wave radar are adjusted, the target detection data sent by the millimeter-wave radar will also change accordingly, so the subsequent processing of the target detection data will also change accordingly, thereby achieving dynamic error compensation.

[0028] Step 5: The trajectory generation module transforms the target detection data through the external reference file to obtain the target information after rough transformation; The external parameter file is saved in the parameter system, and the file contains the transformation matrix of translation T and rotation R. The external parameter file plays a key calibration role in the application of millimeter wave radar, ensuring the precise alignment and fusion of different sensor data, thereby improving the safety and reliability of the autonomous driving system.

[0029] Step 6, filter the static targets in the target information, number and track the dynamic targets, and determine whether it is a new target based on the number; if it is a new target, go to step 5.

[0030] Since the target information includes static objects and dynamic objects, that is, static targets and dynamic targets, it is necessary to filter out static targets first, and then store dynamic targets in the target list, number them and track them. According to the number, it can be judged whether the currently tracked dynamic target is lost, that is, whether the currently tracked dynamic target is a new target. If it is a new target, it means that the original tracked target has been lost, then delete the entire target list, and then go to step 5 to re-perform the rough conversion of the target detection data.

[0031] Step 7: If it is not a new target, the tracking trajectory is saved. When the number of points in the trajectory reaches a preset threshold, the saved tracking trajectory is sent to the trajectory matching module. According to the previous step, if it is not a new target, the tracking track is saved according to the number, and when saving the tracking track, the coordinates need to be offset according to the measurement center of different millimeter-wave radars (for example, the measurement center of the forward millimeter-wave radar 1 is the bottom center, and the measurement center of the corner millimeter-wave radar 2 is the geometric center). Then determine whether the number of points in the tracking track reaches the preset threshold. If it reaches the preset threshold, track matching is performed, such as Figure 3 shown.

[0032] Step 8: The trajectory matching module matches the tracking trajectory of the front corner millimeter-wave radar with the adjacent trajectory in the forward millimeter-wave radar scanning list, and matches the tracking trajectory of the rear corner millimeter-wave radar with the adjacent trajectory in the rearward millimeter-wave radar scanning list; Step 9, when the matching degree exceeds the preset value, the coordinate transformation matrix of the angular millimeter-wave radar and the corresponding forward and backward millimeter-wave radars is used as the update parameter, and the update parameter is written into the external reference file to realize the dynamic compensation of the millimeter-wave radar error; when the matching degree does not exceed the preset value, go to step 5.

[0033] Step 10: After updating the external reference file, go to step 5.

[0034] The present invention provides a system and method for dynamic error compensation based on multiple millimeter wave radars. The technical solution transforms the position and speed of target detection data of multiple millimeter wave radars according to the tracking trajectory of dynamic targets, and then transforms and fuses them for use by downstream modules to achieve dynamic compensation. The technical solution is mainly used to solve the technical problems of the existing technology, such as the small number of millimeter wave radar point clouds, the inability to ensure accuracy, the appearance of redundant targets in data fusion, and the overly rough fusion of targets with different centers of gravity.

[0035] In summary, the embodiments of the present invention provide a system and method for dynamic error compensation based on multiple millimeter-wave radars. This technical solution enables the vehicle to achieve automatic coordinate conversion during movement without relying on other sensors. A relatively stable perception system can be achieved using only a few millimeter-wave radars. This method uses the target center point as the trajectory point, which is relatively accurate. The final compensation value has a high accuracy. If the machine becomes loose and causes the position or heading to change, it can be detected and compensated during operation.

[0036] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An error dynamic compensation system based on multi-millimeter wave radar, applied to intelligent driving vehicles, characterized in that: The system comprises: Millimeter-wave radar, which is installed on the vehicle, includes a forward millimeter-wave radar, a rearward millimeter-wave radar and a corner millimeter-wave radar. When installed, the scanning areas of the forward millimeter-wave radar, the rearward millimeter-wave radar and the corner millimeter-wave radar overlap, and are used to send target detection data and their own status information to the data processing unit after receiving a trigger acquisition signal; A data processing unit is connected to the multiple millimeter-wave radars, and is used to receive target detection data and its own status information from the millimeter-wave radars, and send a trigger acquisition signal and vehicle body information to each millimeter-wave radar; A parameter system, connected to multiple millimeter-wave radars, is used to provide internal reference files to each millimeter-wave radar and save external reference files; The trajectory generation module is connected to the data processing unit and the parameter system, and is used to write the coarse transformation parameters into the internal reference file, transform the target detection data through the external reference file, obtain the target information, filter the static targets according to the target information, number and track the dynamic targets, and judge whether it is a new target according to the number. If not, save the tracking trajectory, and send the saved tracking trajectory to the trajectory matching module when the number of points in the trajectory reaches a preset threshold; The trajectory matching module is connected to the trajectory generation module. After receiving the tracking trajectory, it searches for the adjacent trajectory in the forward or backward millimeter-wave radar scanning list, matches the tracking trajectory of the front corner millimeter-wave radar with the adjacent trajectory in the forward millimeter-wave radar scanning list, and matches the tracking trajectory of the rear corner millimeter-wave radar with the adjacent trajectory in the backward millimeter-wave radar scanning list. When the matching degree exceeds the preset value, the coordinate transformation matrix of the front corner millimeter-wave radar and the corresponding front and backward millimeter-wave radars is used as the update parameter, and the update parameter is written into the external reference file to realize the dynamic compensation of the millimeter-wave radar error.

2. The error dynamic compensation system based on multi-millimeter wave radar according to claim 1, characterized in that: The data processing unit is also used to remove error frames in the target detection data.

3. The error dynamic compensation system based on multi-millimeter wave radar according to claim 1, characterized in that: The data processing unit is also used to send time synchronization data to each millimeter-wave radar to ensure that the target detection data of each millimeter-wave radar is stored in synchronization.

4. The error dynamic compensation system based on multi-millimeter wave radar according to claim 1, characterized in that: The vehicle body information includes gear position, speed, yaw angle, front wheel turning angle, and wheel speed.

5. The error dynamic compensation system based on multi-millimeter wave radar according to claim 1, characterized in that: The internal parameter file includes lateral offset, longitudinal offset, and angular offset; the external parameter file includes translation matrix T and rotation matrix R.

6. The error dynamic compensation system based on multi-millimeter wave radar according to claim 1, characterized in that: The coarse transformation parameters are initial parameters obtained by measuring with a tape measure and an angle measuring instrument.

7. A method for using the error dynamic compensation system based on multi-millimeter wave radar according to claims 1-6, characterized in that: The method comprises: Step 1: The data processing unit sends a trigger acquisition signal to each millimeter wave radar; Step 2: After receiving the trigger acquisition signal, the millimeter wave radar sends the target detection data and its own status information to the data processing unit; Step 3, the trajectory generation module writes the coarse transformation parameters into the internal reference file; Step 4: The parameter system provides the internal parameter file to each millimeter-wave radar according to the status information of the millimeter-wave radar to adjust the internal parameters of each millimeter-wave radar; Step 5: The trajectory generation module transforms the target detection data through the external reference file to obtain the target information after rough transformation; Step 6, filtering static targets in target information, numbering and tracking dynamic targets, and determining whether they are new targets based on the number; Step 7: If it is not a new target, the tracking trajectory is saved. When the number of points in the trajectory reaches a preset threshold, the saved tracking trajectory is sent to the trajectory matching module. Step 8: The trajectory matching module matches the tracking trajectory of the front corner millimeter-wave radar with the adjacent trajectory in the forward millimeter-wave radar scanning list, and matches the tracking trajectory of the rear corner millimeter-wave radar with the adjacent trajectory in the rearward millimeter-wave radar scanning list; Step 9: When the matching degree exceeds the preset value, the coordinate transformation matrix of the angular millimeter-wave radar and the corresponding forward and backward millimeter-wave radars is used as an update parameter, and the update parameter is written into the external reference file to realize dynamic compensation of the millimeter-wave radar error.

8. The error dynamic compensation method based on multi-millimeter wave radar according to claim 7, characterized in that: The step 7 also includes: if it is a new target, go to step 5.

9. The error dynamic compensation method based on multi-millimeter wave radar according to claim 7, characterized in that: The step 9 also includes: when the matching degree does not exceed the preset value, go to step 5.

10. The error dynamic compensation method based on multi-millimeter wave radar according to claim 7, characterized in that: The system also includes: step 10, after updating the external reference file, go to step 5.

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