A method and apparatus for testing the performance of an automatic braking system for unmanned vehicles.

Abstract

This invention provides a method and apparatus for testing the performance of an autonomous vehicle's automatic braking system. The method includes: acquiring the initial speed of the test vehicle when it triggers a braking signal; dividing the performance test into three braking periods; acquiring the time of each of the three braking periods; calculating the corresponding travel distance based on the initial speed; calculating a first braking distance based on the travel distances of the three braking periods; acquiring the braking start and stop positions of the test vehicle using inertial navigation technology; calculating a second braking distance; performing a weighted average of the first and second braking distances to obtain a target braking distance; calculating the average deceleration of the test vehicle during braking; evaluating the performance of the automatic braking system of the test vehicle based on the target braking distance and the average deceleration; and generating a corresponding evaluation report. This invention enables accurate evaluation of the performance of an autonomous vehicle's automatic braking system, offering high reliability and ease of review.

Description

Technical Field

[0001] This invention relates to the field of unmanned vehicle testing technology, and in particular to a testing method and apparatus for the performance of an unmanned vehicle's automatic braking system. Background Technology

[0002] With the emergence and development of functional driverless vehicles, many automated control systems are involved, enabling autonomous driving that replaces humans. Examples include last-mile delivery vehicles that eliminate the driver's cab, removing actuators such as steering wheels, accelerator pedals, and brake pedals. Active safety of driverless vehicles is receiving increasing attention. Automatic braking systems are part of autonomous driving systems. When an obstacle appears in front of the driverless vehicle that could potentially cause a collision, the braking system uses sensors to detect the distance between the obstacle and the vehicle, calculates a safe distance based on the current speed, and activates when the distance between the vehicle and the obstacle is less than the safe distance. This braking reduces the vehicle's speed and prevents a collision.

[0003] Therefore, in order to improve the safety of automatic braking systems, there is an urgent need for a method to perform performance testing on automatic braking systems. Summary of the Invention

[0004] Therefore, it is necessary to provide a testing method and apparatus for the performance of an autonomous vehicle's automatic braking system to address the aforementioned technical problems.

[0005] A method for testing the performance of an autonomous vehicle's automatic braking system includes the following steps: In a performance test of the vehicle's automatic braking system, the initial speed of the test vehicle when it triggers a braking signal is acquired. The performance test includes three braking periods: a braking delay period, a first braking period, and a second braking period. The time of each of the three braking periods is acquired, and the travel distance for each braking period is calculated based on the initial speed. A first braking distance is calculated based on the travel distance of the three braking periods. The braking start position and braking stop position of the test vehicle are acquired using inertial navigation technology, and a second braking distance is calculated. A weighted average of the first and second braking distances is performed to obtain a target braking distance, and the average deceleration of the test vehicle during braking is calculated. The performance of the automatic braking system of the test vehicle is evaluated based on the target braking distance and the average deceleration, and an evaluation report is generated.

[0006] In one embodiment, before acquiring the initial speed of the test vehicle when it triggers the braking signal, the method further includes: calibrating the outline of the test vehicle through a calibration antenna, receiving and parsing the GPS signal of the test vehicle, acquiring the motion information of the test vehicle's CAN signal, positioning data, speed, acceleration, and longitudinal acceleration change curvature; determining whether the test vehicle has triggered the braking signal based on the GPS signal; and acquiring the initial speed when the test vehicle triggers the braking signal.

[0007] In one embodiment, the step of acquiring the time of the three braking periods respectively and calculating the driving distance for the corresponding braking period in combination with the initial speed includes: during the braking delay period, acquiring the delay time of the test vehicle and calculating the delay distance in combination with the initial speed; during the first braking period, the deceleration of the test vehicle increases to the maximum target deceleration, acquiring the first braking time, and calculating the first driving distance and the instantaneous speed of the test vehicle when it reaches the maximum target deceleration in combination with the initial speed, the maximum target deceleration and the first braking time; during the second braking period, the deceleration of the test vehicle decreases to 0, the vehicle stops after braking, acquiring the second braking time, and calculating the second driving distance in combination with the instantaneous speed.

[0008] In one embodiment, the step of acquiring the delay time of the test vehicle during the braking delay period and calculating the delay distance in combination with the initial speed includes: after receiving the braking signal, acquiring the delay time from receiving the braking signal to the start of increasing braking force; and calculating the delay distance of the test vehicle in combination with the initial speed, using the following formula:

[0009] d1 = v b ·t a (1)

[0010] In the formula, v b Let t be the initial velocity. a This is the delay time.

[0011] In one embodiment, during the first braking period, the deceleration of the test vehicle increases to the maximum target deceleration, the first braking time is obtained, and the first travel distance and the instantaneous speed of the test vehicle when it reaches the maximum target deceleration are calculated by combining the initial speed, the maximum target deceleration, and the first braking time. This includes: when the test vehicle begins braking, obtaining the maximum target deceleration of the test vehicle and the first braking time from the start of the increase in braking force to reaching the maximum braking force; assuming the instantaneous vehicle speed after the braking time t is v. t Then there is

[0012]

[0013] In the formula, a0 is the maximum target deceleration, t s Let t be the first braking time; then t s The acceleration over time is:

[0014]

[0015] When decelerating, If the value is negative, t s The speed of the test vehicle within the specified time period is:

[0016]

[0017] Then t s The distance the vehicle travels from the start of braking to the first point before reaching the maximum target deceleration within the test time is:

[0018]

[0019] If we take the initial speed as the speed at which the vehicle's deceleration begins to increase, then after time t... s After reaching the maximum braking deceleration a0, the instantaneous vehicle speed is:

[0020]

[0021] In one embodiment, during the second braking period, the deceleration of the test vehicle decreases to 0, the vehicle stops upon braking, the second braking time is acquired, and the second travel distance is calculated by combining the instantaneous speed. This includes: during the second braking period, the deceleration of the test vehicle continues from the maximum target deceleration until the braking ends, and the vehicle speed decreases from the instantaneous speed to v. f Then the second braking time is:

[0022]

[0023] Based on the second braking time and instantaneous vehicle speed, the second distance traveled by the test vehicle from the maximum target deceleration to the end of braking is calculated as follows:

[0024]

[0025] In the formula, t v This is the second braking time.

[0026] In one embodiment, calculating the first braking distance based on the travel distance during the three braking periods includes: obtaining the first braking distance of the test vehicle based on the braking delay distance, the first travel distance, and the second travel distance, as follows:

[0027]

[0028] In one embodiment, the target braking distance is obtained by weighted averaging the first braking distance and the second braking distance, as shown in the formula:

[0029] d = d a w1+d b w2 (10)

[0030] In the formula, w1 and w2 are the weights of the first braking distance and the second braking distance, respectively.

[0031] In one embodiment, the step of evaluating the performance of the automatic braking system of the test vehicle based on the target braking distance and average deceleration, and generating an evaluation report, includes: obtaining preset braking distance thresholds and deceleration thresholds; comparing the target braking distance and average deceleration with the braking distance thresholds and deceleration thresholds respectively; determining that the automatic braking system performance of the test vehicle is qualified when the target braking distance is less than the braking distance threshold and the average deceleration is greater than the deceleration threshold; and inputting the target braking distance, average deceleration, and evaluation results into an evaluation template to generate an evaluation report.

[0032] A testing device for the performance of an autonomous vehicle automatic braking system, used to implement the testing method for the performance of an autonomous vehicle automatic braking system as described above, includes: an initial speed acquisition module, used to acquire the initial speed of the test vehicle when the braking signal is triggered during the performance test of the vehicle automatic braking system, wherein the performance test includes three braking periods: a braking delay period, a first braking period, and a second braking period; a travel distance calculation module, used to acquire the time of each of the three braking periods and calculate the travel distance for the corresponding braking period based on the initial speed; a first braking distance calculation module, used to calculate a first braking distance based on the travel distance of the three braking periods; a second braking distance calculation module, used to acquire the braking start position and braking stop position of the test vehicle using inertial navigation technology and calculate a second braking distance; a target braking distance acquisition module, used to perform a weighted average of the first braking distance and the second braking distance to obtain a target braking distance and calculate the average deceleration of the test vehicle during the braking process; and a test report generation module, used to evaluate the performance of the automatic braking system of the test vehicle based on the target braking distance and the average deceleration, and generate a test report.

[0033] Compared to existing technologies, the advantages and beneficial effects of this invention are as follows: In the performance test of the vehicle's automatic braking system, the initial speed of the test vehicle when it triggers the braking signal is obtained. The performance test is divided into three braking periods: a braking delay period, a first braking period, and a second braking period. The time of each of the three braking periods is obtained, and the travel distance for the corresponding braking period is calculated based on the initial speed. The first braking distance is calculated based on the travel distance of the three braking periods, improving the accuracy of braking distance measurement. Simultaneously, inertial navigation technology is used to obtain the braking start position and braking stop position of the test vehicle, and the second braking distance is calculated. The first and second braking distances are weighted and averaged to obtain the target braking distance. Combining the two braking distances reduces the adverse effects of measurement errors on the test results, improving the accuracy of the test results. The average deceleration of the test vehicle during braking is calculated, and the performance of the automatic braking system of the test vehicle is evaluated based on the target braking distance and the average deceleration, generating a corresponding evaluation report. This achieves accurate evaluation of the performance of the unmanned vehicle's automatic braking system, with high reliability and ease of viewing the unmanned vehicle's performance. Attached Figure Description

[0034] Figure 1 This is a flowchart illustrating a method for testing the performance of an autonomous vehicle's automatic braking system in one embodiment.

[0035] Figure 2 This is a schematic diagram of the structure of a test device for the performance of an automatic braking system for an unmanned vehicle in one embodiment. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0037] In one embodiment, such as Figure 1 As shown, a test method for the performance of an autonomous vehicle's automatic braking system is provided, including the following steps:

[0038] Step S101: In the performance test of the vehicle automatic braking system, the initial speed of the vehicle when the braking signal is triggered is obtained. The performance test includes three braking periods: braking delay period, first braking period, and second braking period.

[0039] Specifically, during the performance test of the vehicle automatic braking system, an obstacle area is set up on the test road, and the braking system triggering conditions are set. The test vehicle drives towards the obstacle at different speeds. The vehicle's automatic vision sensor identifies the object in front. When the sensor determines that the test vehicle will collide with the obstacle in front, the test vehicle will automatically brake and record the initial speed of the test vehicle when the braking signal is triggered.

[0040] The performance test included three braking periods. The first was the braking delay period, which occurs because there is a time lag between the issuance of the braking signal, the CAN bus signal reaching the control system, and the start of the increase in braking force. The second was the first braking period, which is the time it takes for the braking force to increase from the start of braking to reach the maximum braking force when the test vehicle begins to brake. The third was the second braking period, which is the period from when the test vehicle's automatic braking system comes to a stop, when the braking deceleration reaches the maximum target deceleration, until the end of this braking operation.

[0041] Prior to step S101, the method further includes: calibrating the outline of the test vehicle using a calibration antenna, receiving and parsing the GPS signal of the test vehicle, and obtaining motion information such as the CAN signal, positioning data, speed, acceleration, and longitudinal acceleration curvature of the test vehicle; determining whether the test vehicle has triggered a braking signal based on the GPS signal; and obtaining the initial speed when the test vehicle triggers a braking signal.

[0042] Specifically, during the performance testing of the vehicle's automatic braking system, a calibration antenna can be used to calibrate the outline of the test vehicle. At the same time, the GPS signal of the test vehicle is received and analyzed, and the motion information of the test vehicle, including CAN signal, positioning data, position, speed, acceleration, and longitudinal acceleration curvature, is output. Based on the information in the acquired GPS signal, it is determined whether the test vehicle has triggered a braking signal. When the braking signal is triggered, the current initial speed of the vehicle is acquired to facilitate the testing of the automatic braking system performance of the test vehicle.

[0043] Step S102: Obtain the time of each of the three braking periods, and calculate the travel distance during the corresponding braking period by combining the initial speed.

[0044] Specifically, since the time and travel distance are different during different braking periods, the time experienced during the three braking periods can be recorded separately, and the travel distance during the corresponding braking period can be calculated by combining the initial speed, so as to make the braking distance more accurate.

[0045] Step S102 includes: during the braking delay period, acquiring the delay time of the test vehicle and calculating the delay distance by combining it with the initial speed; during the first braking period, the deceleration of the test vehicle increases to the maximum target deceleration, acquiring the first braking time, and calculating the first travel distance and the instantaneous speed of the test vehicle when it reaches the maximum target deceleration by combining the initial speed, the maximum target deceleration and the first braking time; during the second braking period, the deceleration of the test vehicle decreases to 0, the vehicle stops after braking, acquiring the second braking time, and calculating the second travel distance by combining it with the instantaneous speed.

[0046] Specifically, during the braking delay period, the braking command is issued but braking does not begin. Therefore, the delay time during this period can be obtained, and the delay distance can be calculated by combining it with the initial speed. During the first braking period, the deceleration of the test vehicle increases to the maximum target deceleration, the value of which is the same as the acceleration of the test vehicle at the start of braking. At the same time, the braking force also increases from the start of braking to reaching the maximum braking force. By obtaining the first braking test data, combined with the initial speed, the maximum target deceleration, and the first braking time, the first travel distance can be obtained, as well as the instantaneous speed of the test vehicle when it reaches the maximum target deceleration, so as to facilitate the calculation of the second travel distance. During the second braking period, the measured deceleration decreases from the maximum target deceleration to 0, the braking ends, and the vehicle comes to a stop. The second braking time during this period is obtained, and combined with the instantaneous speed, the second travel distance is calculated. Thus, the braking distance generated by the test vehicle during the entire period from the start of braking to the stop of braking can be calculated. Segmented calculation improves the accuracy of the braking distance, thereby improving the reliability of the performance evaluation results.

[0047] The steps for obtaining the delay distance during the braking delay period are as follows: After receiving the braking signal, obtain the delay time from receiving the braking signal to the start of the increase in braking force; combine this with the initial speed to calculate the delay distance of the test vehicle, using the following formula:

[0048] d1 = v b ·t a (1)

[0049] In the formula, v b Let t be the initial velocity. a This is the delay time.

[0050] The step of obtaining the first travel distance during the first braking period is as follows: when the test vehicle begins to brake, obtain the maximum target deceleration of the test vehicle and the first braking time from the start of the increase in braking force to reaching the maximum braking force; assuming the instantaneous vehicle speed after the braking time t is v t Then there is

[0051]

[0052] In the formula, a0 is the maximum target deceleration, t s Let t be the first braking time; then t s The acceleration over time is:

[0053]

[0054] When decelerating, If the value is negative, t s The speed of the test vehicle within the specified time period is:

[0055]

[0056] Then t s The distance the vehicle travels from the start of braking to the first point before reaching the maximum target deceleration within the test time is:

[0057]

[0058] If we take the initial speed as the speed at which the vehicle's deceleration begins to increase, then after time t... s After reaching the maximum braking deceleration a0, the instantaneous vehicle speed is:

[0059]

[0060] The step of obtaining the second travel distance during the second braking period is as follows: During the second braking period, the deceleration of the test vehicle continues from the maximum target deceleration until the end of braking, and the vehicle speed decreases from the instantaneous speed to v. f Then the second braking time is:

[0061]

[0062] Based on the second braking time and instantaneous vehicle speed, the second distance traveled by the test vehicle from the maximum target deceleration to the end of braking is calculated as follows:

[0063]

[0064] In the formula, t v This is the second braking time.

[0065] Step S103: Calculate the first braking distance based on the travel distance during the three braking periods.

[0066] Specifically, since the vehicle braking distance is determined by the travel distance during three braking periods, the first braking distance is obtained by adding the three travel distances together after obtaining the travel distances during the three braking periods. By dividing the vehicle braking process into three braking periods and calculating the travel distance for each braking period separately, the calculation accuracy for each braking period can be improved, the impact of measurement errors on the final result can be reduced, and the overall calculation accuracy can be improved.

[0067] Step S103 includes: obtaining the first braking distance of the test vehicle based on the braking delay distance, the first travel distance, and the second travel distance, as follows:

[0068]

[0069] Step S104: Using inertial navigation technology, the braking start position and braking stop position of the test vehicle are obtained, and the second braking distance is calculated.

[0070] Specifically, during the performance testing of the vehicle's automatic braking system, inertial navigation technology is used simultaneously to obtain the braking start position and braking stop position of the test vehicle, thereby calculating the second braking distance obtained through inertial navigation technology. By using both inertial navigation technology and measurement calculation methods to obtain the braking distance of the test vehicle, the accuracy and reliability of the test results can be further improved.

[0071] Step S105: Perform a weighted average of the first braking distance and the second braking distance to obtain the target braking distance, and calculate the average deceleration of the test vehicle during the braking process.

[0072] Specifically, due to inherent errors in data acquisition, to improve the accuracy of test data, the first and second braking distances are weighted and averaged according to preset braking distance weights to obtain the corresponding target braking distance. Simultaneously, the braking time from the start of braking to complete stop is calculated using the delay time, the first braking time, and the second braking time. Alternatively, the average deceleration of the test vehicle during braking can be calculated by directly measuring the braking time and combining it with the target braking distance. This allows for the evaluation of the automatic braking system performance of the test vehicle based on the target braking distance and average deceleration, resulting in a more comprehensive and accurate evaluation.

[0073] The formula for calculating the target braking distance is as follows:

[0074] d = d a w1+d s w2 (10)

[0075] In the formula, w1 and w2 are the weights of the first braking distance and the second braking distance, respectively.

[0076] Specifically, testers can configure the weights of the first braking distance and the second braking distance according to the actual situation, which meets the actual needs and can improve the accuracy of the calculation results.

[0077] Step S106: Evaluate the performance of the automatic braking system of the test vehicle based on the target braking distance and average deceleration, and generate an evaluation report.

[0078] Specifically, based on the obtained target braking distance and average deceleration, the performance of the automatic braking system of the test vehicle is evaluated, the evaluation results are obtained, and the evaluation results are input into a pre-configured evaluation template to generate a corresponding evaluation report.

[0079] Step S106 includes: obtaining preset braking distance thresholds and deceleration thresholds; comparing the target braking distance and average deceleration with the braking distance thresholds and deceleration thresholds respectively; when the target braking distance is less than the braking distance threshold and the average deceleration is greater than the deceleration threshold, the automatic braking system of the test vehicle is deemed to be qualified; inputting the target braking distance, average deceleration and evaluation results into the evaluation template to generate an evaluation report.

[0080] Specifically, preset braking distance and deceleration thresholds are used; for example, the braking distance threshold is set to 20m and the deceleration threshold is set to 5.9m / s. 2 The relationship between the target braking distance and average deceleration and the braking distance threshold and deceleration threshold were compared, respectively, when the target braking distance was less than 20m and the average deceleration was greater than 5.9m / s. 2 When the automatic braking system of the test vehicle is deemed to be qualified, the test vehicle information, such as target braking distance, average deceleration, initial speed, and maximum deceleration, as well as the evaluation results, are entered into the evaluation template to generate an evaluation report, so as to make it easier to view the performance of the automatic braking system of the test vehicle more intuitively.

[0081] In this embodiment, during the performance test of the vehicle's automatic braking system, the initial speed of the test vehicle when the braking signal is triggered is obtained. The performance test is divided into three braking periods: a braking delay period, a first braking period, and a second braking period. The time of each of the three braking periods is obtained, and the travel distance for the corresponding braking period is calculated based on the initial speed. The first braking distance is calculated based on the travel distance of the three braking periods, improving the accuracy of the braking distance measurement. Simultaneously, inertial navigation technology is used to obtain the braking start position and braking stop position of the test vehicle, and the second braking distance is calculated. The first braking distance and the second braking distance are weighted and averaged to obtain the target braking distance. Combining the two braking distances can reduce the adverse effects of measurement errors on the test results and improve the accuracy of the test results. The average deceleration of the test vehicle during the braking process is calculated. The performance of the automatic braking system of the test vehicle is evaluated by combining the target braking distance and the average deceleration, and a corresponding evaluation report is generated. This achieves accurate evaluation of the performance of the automatic braking system of the unmanned vehicle, with high reliability and convenient viewing of the unmanned vehicle's performance.

[0082] like Figure 2 As shown, a testing device 20 for the performance of an autonomous vehicle automatic braking system is provided, used to implement the testing method for the performance of an autonomous vehicle automatic braking system as described above. It includes: an initial speed acquisition module 21, a travel distance calculation module 22, a first braking distance calculation module 23, a second braking distance calculation module 24, a target braking distance acquisition module 25, and a test report generation module 26, wherein:

[0083] The initial speed acquisition module 21 is used to acquire the initial speed of the test vehicle when the braking signal is triggered during the performance test of the vehicle automatic braking system. The performance test includes three braking periods: braking delay period, first braking period, and second braking period.

[0084] The driving distance calculation module 22 is used to obtain the time of the three braking periods respectively, and calculate the driving distance of the corresponding braking period by combining the initial speed;

[0085] The first braking distance calculation module 23 is used to calculate the first braking distance based on the travel distance during the three braking periods;

[0086] The second braking distance calculation module 24 is used to obtain the braking start position and braking stop position of the test vehicle using inertial navigation technology, and calculate the second braking distance.

[0087] The target braking distance acquisition module 25 is used to perform a weighted average of the first braking distance and the second braking distance to obtain the target braking distance, and to calculate the average deceleration of the test vehicle during the braking process.

[0088] The evaluation report generation module 26 is used to evaluate the performance of the automatic braking system of the test vehicle based on the target braking distance and average deceleration, and generate an evaluation report.

[0089] In one embodiment, the driving distance calculation module 22 is specifically used for: during the braking delay period, acquiring the delay time of the test vehicle and calculating the delay distance by combining it with the initial speed; during the first braking period, when the deceleration of the test vehicle increases to the maximum target deceleration, acquiring the first braking time, and calculating the first driving distance and the instantaneous speed of the test vehicle when it reaches the maximum target deceleration by combining the initial speed, the maximum target deceleration and the first braking time; during the second braking period, when the deceleration of the test vehicle decreases to 0, the vehicle stops after braking, acquiring the second braking time, and calculating the second driving distance by combining it with the instantaneous speed.

[0090] In one embodiment, the evaluation report generation module 26 is specifically used to: obtain preset braking distance thresholds and deceleration thresholds; compare the target braking distance and average deceleration with the braking distance thresholds and deceleration thresholds respectively; when the target braking distance is less than the braking distance threshold and the average deceleration is greater than the deceleration threshold, determine that the automatic braking system performance of the test vehicle is qualified; input the target braking distance, average deceleration and evaluation results into the evaluation template to generate an evaluation report.

[0091] In one embodiment, the device further includes: an inertial navigation positioning module and a data processor, the inertial navigation positioning module being electrically connected to the data processor; the inertial navigation positioning module includes an antenna and an inertial navigation measurement unit, the antenna being used to calibrate the outline of the test vehicle and receive GPS signals; the inertial navigation measurement unit being used to parse the GPS signals and output the motion information of the test vehicle, wherein the motion information includes GPS latitude and longitude information, deceleration, acceleration, heading angle, and angular velocity; the data processor being used to receive the motion information sent by the inertial navigation measurement unit, and to perform performance analysis on the braking system performance of the test vehicle based on the motion information, thereby obtaining an evaluation report.

[0092] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), or random access memory (RAM), etc.

[0093] It is obvious to those skilled in the art that the modules or steps of the present invention described above can be implemented using general-purpose computing devices. They can be centralized on a single computing device or distributed across a network of multiple computing devices. Optionally, they can be implemented using computer-executable program code, thereby storing them in a computer storage medium (ROM / RAM, magnetic disk, optical disk) for execution by the computing device. In some cases, the steps shown or described can be performed in a different order than those described herein, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Therefore, the present invention is not limited to any particular hardware and software combination.

[0094] The above description, in conjunction with specific embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific implementation of the present invention is limited to these descriptions. For those skilled in the art, various simple deductions or substitutions can be made without departing from the concept of the present invention, and all such deductions or substitutions should be considered within the scope of protection of the present invention.

Claims

1. A method for testing performance of an automatic braking system of an unmanned vehicle, the method comprising: The method comprises the following steps: ​ In a performance test experiment of an automatic braking system of a vehicle, an initial speed of a test vehicle when a braking signal is triggered is obtained, the performance test experiment comprises three braking periods of a braking delay period, a first braking period and a second braking period; Times of the three braking periods are respectively obtained, and distances of travel in the corresponding braking periods are calculated in combination with the initial speed; A first braking distance is calculated according to the distances of travel in the three braking periods; Inertial navigation technology is used to obtain a braking start position and a braking stop position of the test vehicle, and a second braking distance is calculated; A target braking distance is obtained by weighted averaging of the first braking distance and the second braking distance, and an average deceleration of the test vehicle in the braking process is calculated; The performance of the automatic braking system of the test vehicle is evaluated according to the target braking distance and the average deceleration, and an evaluation report is generated.

2. The method of claim 1, wherein, Before the initial speed of the test vehicle when the braking signal is triggered is obtained, the method further comprises the following steps: The profile of the test vehicle is calibrated by a calibration antenna, GPS signals of the test vehicle are received and analyzed, CAN signals, positioning data positions, speeds, accelerations, longitudinal acceleration change curvatures and other motion information of the test vehicle are obtained; It is judged whether the test vehicle triggers a braking signal according to the GPS signals; The initial speed is obtained when the test vehicle triggers the braking signal.

3. The method of claim 1, wherein, The times of the three braking periods are respectively obtained, and the distances of travel in the corresponding braking periods are calculated in combination with the initial speed, comprising the following steps: In the braking delay period, a delay time of the test vehicle is obtained, and a delay distance is calculated in combination with the initial speed; In the first braking period, the deceleration of the test vehicle increases to a maximum target deceleration, a first braking time is obtained, and a first distance of travel and an instantaneous speed of the test vehicle when the maximum target deceleration is reached are calculated in combination with the initial speed, the maximum target deceleration and the first braking time; In the second braking period, the deceleration of the test vehicle decreases to 0, the braking ends and the vehicle stops, a second braking time is obtained, and a second distance of travel is calculated in combination with the instantaneous speed.

4. The method of claim 3, wherein the method further comprises: In the braking delay period, a delay time of the test vehicle is obtained, and a delay distance is calculated in combination with the initial speed, comprising the following steps: After receiving the braking signal, a delay time from receiving the braking signal to the start of the increase in braking force is obtained; In combination with the initial speed, the delay distance of the test vehicle is calculated, and the formula is: ， In the formula, is the initial velocity, is the delay time.

5. The method of claim 4, wherein the method further comprises: In the first braking period, the deceleration of the test vehicle increases to a maximum target deceleration, a first braking time is obtained, and a first distance of travel and an instantaneous speed of the test vehicle when the maximum target deceleration is reached are calculated in combination with the initial speed, the maximum target deceleration and the first braking time, comprising the following steps: When the test vehicle starts braking, the maximum target deceleration of the test vehicle and the first braking time experienced by the increase in braking force from the start to the maximum braking force are obtained; Assuming the instantaneous vehicle speed after experiencing the braking time t is then there is ， In the formula, is the maximum target deceleration, is the first braking time; Then The acceleration over time is: when decelerating, is negative, the speed of the test vehicle over time is: Then The first travel distance of the test vehicle before starting braking to the maximum target deceleration within the time is: The initial vehicle speed is taken as the vehicle speed at which the vehicle begins to increase in deceleration, and the elapsed time after the maximum braking deceleration is reached The instantaneous vehicle speed after 。 6. The method of claim 5, wherein the method further comprises: In the second braking period, the deceleration of the test vehicle decreases to 0, the braking ends and the vehicle stops, a second braking time is obtained, and a second distance of travel is calculated in combination with the instantaneous speed. During the second braking, the deceleration of the test vehicle continues from the maximum target deceleration to the end of braking, and the vehicle speed is reduced from the instantaneous vehicle speed to The second braking time is then: ， According to the second braking time and the instantaneous vehicle speed, a second travel distance of the test vehicle from the maximum target deceleration to the end of braking is calculated as: ， In the formulae, is the second braking time.

7. The method of claim 6, wherein the method further comprises: The first braking distance is calculated according to the travel distances during the three braking periods, including: The first braking distance of the test vehicle is obtained according to the delay distance, the first travel distance and the second travel distance, and is calculated as: 。 8. The method of claim 7, wherein the method further comprises: The target braking distance is obtained by weighted averaging the first braking distance and the second braking distance, and the formula is: ， wherein and are the weights of the first and second braking distances, respectively.

9. The method of claim 1, wherein, The performance of the automatic braking system of the test vehicle is evaluated according to the target braking distance and the average deceleration, and an evaluation report is generated, including: A preset braking distance threshold and deceleration threshold are obtained, and the relationship between the target braking distance and the average deceleration and the braking distance threshold and the deceleration threshold is compared; When the target braking distance is less than the braking distance threshold and the average deceleration is greater than the deceleration threshold, it is determined that the performance of the automatic braking system of the test vehicle is qualified; The target braking distance and the average deceleration and the evaluation result are input into an evaluation template to generate an evaluation report.

10. A device for testing the performance of an automatic braking system of an unmanned vehicle, characterized in that, A test method for the performance of an automatic braking system of an unmanned vehicle according to any one of claims 1-9, comprising: An initial speed acquisition module for acquiring the initial speed of the test vehicle when triggering the braking signal in the performance test of the vehicle automatic braking system, wherein the performance test includes three braking periods of the braking delay period, the first braking period and the second braking period; A travel distance calculation module for acquiring the time of the three braking periods respectively, and calculating the travel distance of the corresponding braking period in combination with the initial speed; A first braking distance calculation module for calculating the first braking distance according to the travel distances during the three braking periods; A second braking distance calculation module for obtaining the braking start position and the braking stop position of the test vehicle by using the inertial navigation technology, and calculating the second braking distance; A target braking distance acquisition module for obtaining the target braking distance by weighted averaging the first braking distance and the second braking distance, and calculating the average deceleration of the test vehicle during braking; An evaluation report generation module for evaluating the performance of the automatic braking system of the test vehicle according to the target braking distance and the average deceleration, and generating an evaluation report.

Images