An automatic driving function dynamic verification system and method

Abstract

The present application relates to a kind of automobile automatic driving function dynamic verification system and method, including millimeter wave radar target simulator, wave-absorbing box, chassis dynamometer system, virtual scene simulation system, test management and automatic test module, linear motor and rack, the front of wave-absorbing box is provided with the open box mouth, the front of box mouth is directly opposite the front radar of the car, the back of wave-absorbing box is installed with the radio frequency head antenna of millimeter wave radar target simulator, and the inner wall of wave-absorbing box is provided with wave-absorbing cotton layer.The ADAS function test of automatic driving vehicle is changed from the actual road of outdoor test field to indoor laboratory environment, and the problems such as limited outdoor test site, higher test risk and inability to test without automatic driving test license are solved.The present application has the advantages of low test cost, good repeatability, reliable test verification system environment, saving vehicle road test time and cost.

Description

TECHNICAL FIELD

[0001] The application relates to an automatic driving function dynamic verification system and method, and belongs to the technical field of automatic driving. BACKGROUND

[0002] Automatic driving is a technology that enables a vehicle to complete the entire driving process without or with less driver manipulation. According to the degree of automation, the International Society of Automotive Engineers (SAE) divides automatic driving into six levels: L0 (no automation), L1 (driving assistance), L2 (partial automation), L3 (conditional automation), L4 (high automation), and L5 (complete automation).

[0003] Advanced Driver Assistance System (ADAS) is a necessary condition for realizing L1-L3 level automatic driving, and is also a necessary way to advance to L4 and L5 level automatic driving technology. The ADAS system is divided into three modules: environment perception, calculation analysis and control execution. Various sensors (millimeter wave radar, laser radar, ultrasonic radar, infrared, single / dual camera, satellite navigation, etc.) installed on the vehicle monitor the driver, vehicle and its driving environment in real time during driving, and assist the driver in performing driving tasks or actively avoiding collisions and other injuries through information and motion control.

[0004] With the continuous improvement of the automation level of vehicles, the application of ADAS system functions is also increasing, such as adaptive cruise control (ACC), automatic emergency braking (AEB), blind spot detection (BSD), lane departure warning (LDW), lane keeping assistance (LKA), automatic parking assistance (APA), etc. They will intervene or take over the vehicle and driving process to different degrees, and errors in these interventions or takeovers will lead to unpredictable consequences. Therefore, it is particularly important to comprehensively and dynamically test these advanced auxiliary driving functions. The most accurate test is undoubtedly real vehicle road testing, but road testing has many problems:

[0005] 1. Safety is difficult to guarantee when people and vehicles are needed in the test scene;

[0006] 2. The test process is restricted by road surface quality and weather conditions;

[0007] 3. The cost of manpower and site construction is high;

[0008] 4. It is impossible to conduct large-scale 100% full inspection;

[0009] 5. The verification scene and conditions cannot be repeated.

[0010] As an important technology and means to improve safe driving, it is urgent and necessary to conduct 100% dynamic testing on ADAS functions. It is urgent to develop an accurate and effective vehicle ADAS function dynamic testing system and method with controllable cost to meet the needs of future automatic driving vehicle safety testing and improve the quality of vehicle delivery.

[0011] Based on this, the present application is proposed. SUMMARY

[0012] The present application provides a kind of automobile automatic driving function dynamic verification system and method to solve the problems existing in prior art, and the specific technical solutions are as follows:

[0013] A kind of automobile automatic driving function dynamic verification system, comprising:

[0014] Millimeter wave radar target simulator, for generating one or more virtual targets in front of actual vehicle, simulating the vehicle or pedestrian in front of actual road, providing front radar scanning target for the vehicle to test ADAS function;

[0015] Wave-absorbing box, for shielding the interference of surrounding environment in front of the vehicle;

[0016] The front of the wave-absorbing box is provided with an open box mouth, and the front of the box mouth is opposite to the front radar of the vehicle;The back of the wave-absorbing box is provided with a radio frequency head antenna of the millimeter wave radar target simulator, and the inner wall of the wave-absorbing box is provided with a wave-absorbing cotton layer;

[0017] Chassis dynamometer system, for providing road load simulation for actual vehicle;

[0018] Virtual scene simulation system, comprising a graphics workstation and a virtual scene modeling module running on the graphics workstation, the virtual scene modeling module can build a variety of traffic scene models;

[0019] Test management and automatic test module, the virtual scene modeling module interacts with the test management and automatic test module through TCP / IP network interface;The virtual traffic scene in the traffic scene model is output to the scene display screen through HDMI video interface, and the scene display screen is placed in front of the vehicle-mounted camera through gantry and six-degree-of-freedom mechanical arm, to provide dynamic simulation of visual scene for the vehicle-mounted camera;

[0020] The chassis dynamometer system comprises a chassis dynamometer and a chassis dynamometer controller, the four drums of the chassis dynamometer support the four wheels of the actual vehicle, and the chassis dynamometer controller controls the rotation of the drums in real time;

[0021] The virtual target is displayed on the instrument panel of the vehicle after being recognized by the front radar of the vehicle, and the relative distance and speed between the vehicle and the front vehicle are dynamically displayed on the instrument panel;

[0022] The linear motor drives the wave-absorbing box to move left and right in front of the vehicle through the gantry, so that the virtual target generated by the radar simulator is always in front of the vehicle.

[0023] When the vehicle moves left and right on the drum of the chassis dynamometer, the deviation displacement caused by the left and right movement is collected by the laser range finder arranged on the side of the vehicle and output to the chassis dynamometer controller in real time, and the test management and automatic test module obtains the deviation displacement through the ADS communication protocol and controls the linear motor and the six-degree-of-freedom mechanical arm on the gantry to move synchronously in real time.

[0024] The test management and automatic test module obtains the motion data and deviation displacement of the actual vehicle driving on the chassis dynamometer through the ADS communication protocol, and simultaneously interacts with the millimeter wave radar target simulator, six-degree-of-freedom mechanical arm, linear motor and virtual scene simulation system through the TCP / IP network protocol, controls the motion of the virtual target in front of the vehicle, six-degree-of-freedom mechanical arm and wave-absorbing box in real time, and displays the motion state of the vehicle and virtual target in the virtual traffic scene.

[0025] Further improvement, the virtual target includes one or more of virtual vehicles, virtual pedestrians, and virtual animals.

[0026] Further improvement, when testing ACC and AEB, the virtual target is in front of the vehicle.

[0027] When testing LDW and LKA, the virtual traffic scene in the scene display screen is within the field of view of the vehicle-mounted camera.

[0028] Further improvement, the chassis dynamometer controller controls the rotation of the drum in real time, and the driving resistance is F=A+B·v+C·v 2 to provide the vehicle with driving resistance consistent with driving on the road, where F is the driving resistance, the vehicle speed is v, A represents the resistance independent of speed, B represents the first order influence coefficient of speed, and C represents the second order influence coefficient of speed.

[0029] Further improvement, the radio frequency head antenna is arranged along the x direction of the front radar of the vehicle, and the distance between the radio frequency head antenna and the front radar of the vehicle is at least 50 cm.

[0030] When the beam azimuth angle of the front radar of the vehicle is ±60°, the pitch angle is ±10°; the length of the inner wall of the wave-absorbing box is at least 1735mm, the width is at least 500mm, and the height is at least 177mm; the surface of the wave-absorbing cotton layer is provided with a plurality of regular quadrangular pyramid-shaped pyramids in an array, the density of the pyramids on the surface of the wave-absorbing cotton layer is 784 per square meter, the bottom surfaces of adjacent two pyramids are closely connected, the bottom surface length of each pyramid is 3.5cm, the height of each pyramid is 7.5cm, and the thickness of the part of the structure in the wave-absorbing cotton layer without the pyramids is 2.5cm.

[0031] Still further improvement, a kind of automobile automatic driving function dynamic verification method, comprising the following steps:

[0032] Step S1, the distance of front axle and rear axle of chassis dynamometer is adjusted according to the wheelbase size of test vehicle, so that the center of four wheels of test vehicle in step S2 is aligned with the center of four double shafts of chassis dynamometer;

[0033] Step S2, the test vehicle is driven to the test station of chassis dynamometer, and the test vehicle is tied at the trailer hook behind the test vehicle;The test vehicle is referred to as the vehicle;

[0034] Step S3, the parameters of road load simulation are set in the chassis dynamometer controller, and the chassis dynamometer simulates the road load of the vehicle driving on the actual road;

[0035] Step S4, the radio frequency head antenna of millimeter wave radar target simulator on the back of wave-absorbing box is directly opposite the center of front radar of the vehicle;

[0036] Step S5, the position of laser range finder on the right side of the vehicle is adjusted, so that the red laser point emitted by the laser range finder is on the intersection line of the center line of the vehicle's wheel eyebrow and the vertical axis;

[0037] Step S6, open the millimeter wave radar target simulator, and check whether the frequency of the front radar signal received in the frequency domain graph is stable, and whether the radar signal amplitude in the time domain graph is in the range of-1024~1023;If the signal amplitude is not in the above range, adjustment is needed;

[0038] Step S7, a traffic test scene is built in the virtual scene simulation system, which includes static traffic scene model and dynamic traffic participants;The speed and travel distance of the vehicle on the chassis dynamometer are associated with the test vehicle model in the traffic test scene, so that the motion parameters of the vehicle on the chassis dynamometer are consistent with the test vehicle model in the traffic test scene;

[0039] Step S8, starting the test management and automatic test module, which includes a login interface, a test operation interface and a state display interface; wherein the test operation interface is used for the user to connect the test equipment communication, to drive the equipment operation, to start and stop each test process, to display or hide the state display interface; the state display interface is placed in front of the driver, used to prompt the driver the current test content and the operation of each test step, and to display the real-time speed, acceleration, relative distance and displacement of the vehicle offset from the middle of the chassis dynamometer drum of the vehicle and the virtual target; starting the test management and automatic test module in sequence carries out user identity verification, initialization, reads the offset displacement caused by vehicle movement and left and right movement through ADS communication, connects the millimeter wave radar target simulator and the six-degree-of-freedom mechanical arm through TCP / IP communication, and sends the motion data of the vehicle and the virtual target to the virtual scene simulation system through UDP communication; only when the above communication and data interaction are all normal, the automatic driving function detection test process is started;

[0040] Step S9, recording test data and observing test situation at any time, terminating test in time when abnormality occurs; analyzing test results, adjusting the corresponding time of vehicle speed and ACC or LDW / LKA test steps on the chassis dynamometer in the program of the test management and automatic test module, the speed and distance change frequency of the virtual target generated by the millimeter wave radar target simulator, optimizing the following vehicle following, collision effect, lane line length, turning angle in the virtual traffic scene, and starting the test again until the ideal test effect is obtained.

[0041] Further improvement, in step S3, the longitudinal resistance received by the automobile during driving includes: rolling resistance F f , air resistance F w , slope resistance F s and acceleration resistance F a , which are collectively referred to as the driving resistance F of the automobile:

[0042] F=F f +F w +F s +F a ;

[0043] The rolling resistance can be expressed as the product of the wheel load and the rolling resistance coefficient, that is:

[0044] F f =W·f=mg cosθ·f;

[0045] In the formula, m is the mass of the automobile, the unit is kg; g is the acceleration of gravity; θ is the road slope; f is the rolling resistance coefficient, which satisfies the following relationship on good road surface:

[0046]

[0047] Air resistance is the force of air acting on the car in the direction of travel, its value is proportional to the dynamic pressure of the relative velocity of airflow, namely:

[0048]

[0049] In the formula, C d is the air resistance coefficient, 0.2-0.4; ρ is the air density, taken as ρ = 1.2258 N·s 2 / m 4 ; u r is the relative speed of the vehicle relative to the air, which is the speed of the car v when there is no wind, unit m / s; A f is the frontal area of the car, unit m 2 , that is, the projection area of the car in the direction of travel;

[0050] When the speed of the car is in km / h, the air resistance can be expressed as:

[0051]

[0052] The slope resistance is the force of gravity along the road surface when the car is driving uphill or downhill, which can be expressed as: F s = mg·sinθ;

[0053] The acceleration resistance is the inertial force of the car's mass when accelerating, which can be expressed as: F a = m·a; In the formula, a is the acceleration of the car when driving, unit m / s 2 ;

[0054] Based on the above analysis, the resistance of the car driving on the actual road surface is:

[0055]

[0056] Let A represent the speed-independent resistance, unit N; let B represent the first-order speed influence coefficient, unit N / (km / h); let C represent the second-order speed influence coefficient, unit N / (km / h) 2 ; then the driving resistance of the car can be written as:

[0057] F = A + Bv + Cv 2 + mg·sinθ + m·a

[0058] If the car is driving at a constant speed on a horizontal road, the values of the slope resistance and the acceleration resistance are zero, and at this time the driving resistance of the car is:

[0059] F = A + Bv + Cv 2 .

[0060] Further improvement, in step S7, the static traffic scene model contains one or several of the road, road marking line, traffic sign, traffic light, building, and the dynamic traffic participant contains one or several of the traffic vehicle model, pedestrian model, test vehicle model.

[0061] Further improvement, in step S8, each test procedure is as follows:

[0062] Step S81, full-speed-area constant-speed cruise test: the driver starts the car, lightly presses the accelerator to accelerate to 25km / h, releases the accelerator and turns on the vehicle ACC, changes the speed from the default value 30 to 40, and observes whether the vehicle speed immediately increases from 25km / h to 40km / h at a constant speed and can be maintained for more than 5s; then changes the ACC setting value by reducing 10 and then increasing 10, and observes whether the vehicle speed immediately increases and decreases following the ACC setting value;

[0063] Step S82, ACC deceleration test: set the speed of the virtual target front vehicle to 30km / h, which is 40km / h lower than the ACC speed of the vehicle, and observe whether the front vehicle is displayed on the vehicle instrument panel and the distance from far to near, and whether the vehicle speed decreases from 40km / h to 30km / h at a constant speed and is maintained;

[0064] Step S83, ACC acceleration test: set the speed of the virtual target front vehicle to 35km / h, and observe whether the vehicle speed increases from 30km / h to 35km / h at a constant speed and is maintained; then set the speed of the virtual target front vehicle to 50km / h, which is 40km / h higher than the ACC speed of the vehicle, and observe whether the vehicle speed restores to 40km / h at a constant speed and is maintained, and does not continue to increase to 50km / h;

[0065] Step S84, ACC parking and automatic starting test: gradually reduce the speed of the virtual target front vehicle until it is 0, and observe whether the front vehicle on the vehicle instrument panel gradually approaches, and whether the speed of the vehicle gradually decreases until it stops; set the speed of the virtual target front vehicle from 0 to gradually increase to 30km / h, and observe whether the front vehicle on the vehicle instrument panel gradually moves away, and whether the vehicle gradually accelerates until the speed stabilizes at 30km / h;

[0066] Step S85, LDW and LKA test: turn on the LDW and LKA functions of the vehicle, and observe whether there is an identification of the function being turned on on the vehicle instrument panel; the vehicle travels at a constant speed, enters the road with a curve in the virtual traffic scene, releases the steering wheel at the curve, and observes whether there is an audible and visual warning of lane deviation warning, and whether the vehicle travels in the virtual traffic scene without exceeding the lane line by 0.4m, and the steering wheel can automatically correct the deviation and return to the center of the lane.

[0067] The beneficial effects of the application are:

[0068] 1. The application enriches the research and development and test method of automatic driving technology, and tests the ADAS function of the automatic driving vehicle in the indoor laboratory environment instead of the actual road of the outdoor test field, so as to solve the problems of limited outdoor test field, high test danger and inability to test due to the lack of automatic driving test license.

[0069] 2. The test cost is low, and the repeatability is good. By changing the different relative distances and speeds between the virtual target vehicle generated by the millimeter wave radar target simulator and the vehicle, the test of ACC, AEB, LDW, LKA and other functions can be quickly and conveniently switched. The virtual scene simulation system can conveniently establish various traffic scenes, and can repeatedly test a certain scene.

[0070] 3. The test verification system environment is real and reliable. The chassis dynamometer used in the system can accurately simulate the road load of the actual vehicle driving on the actual road surface. The millimeter wave radar target simulator provides a virtual target with consistent radar reflection characteristics as the real target vehicle for the front radar of the actual vehicle, so that the test in the laboratory environment is the same as the actual road effect, which saves the time and cost of vehicle road test. BRIEF DESCRIPTION OF DRAWINGS

[0071] Figure 1 It is a schematic diagram of the automatic driving function dynamic verification system of the application;

[0072] Figure 2 It is a schematic diagram of the automatic driving function dynamic verification system of the application;

[0073] Figure 3 It is an expert interface diagram of the millimeter wave radar target simulator;

[0074] Figure 4 It is a time domain diagram of the radar signal received by the millimeter wave radar target simulator;

[0075] Figure 5 It is a physical diagram of the wave absorption box;

[0076] Figure 6 It is a physical diagram of the wave absorption cotton layer in the wave absorption box;

[0077] Figure 7 It is a scene diagram displayed on the instrument panel when the wave absorption box is not completely shielded;

[0078] Figure 8 It is a scene diagram displayed on the instrument panel when the wave absorption box is completely shielded;

[0079] Figure 9 It is a state diagram when the ACC is normally started and the ACC speed is set when the wave absorption box is completely shielded;

[0080] Figure 10The state diagram when the ACC is started or the ACC test is being performed as described above, and an obstacle suddenly appears in front of the vehicle. DETAILED DESCRIPTION

[0081] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application.

[0082] Embodiment 1

[0083] As shown in Figure 1 , 2 , the automobile automatic driving function dynamic verification system comprises:

[0084] A millimeter wave radar target simulator (simply referred to as a radar target simulator) is used to generate one or more virtual targets in front of an actual vehicle, simulate vehicles or pedestrians in front of the vehicle on an actual road surface, and provide the virtual targets for ADAS function testing of a front radar scanning target of the vehicle; wherein the virtual targets include one or more of virtual vehicles, virtual pedestrians, and virtual animals. When the virtual target is a virtual vehicle, it is simply referred to as a virtual target vehicle. The vehicle is also the actual vehicle.

[0085] A wave-absorbing box is used to shield the interference of the surrounding environment in front of the vehicle.

[0086] The front of the wave-absorbing box is provided with an open box opening, and the front of the box opening is directly opposite the front radar of the vehicle. The back of the wave-absorbing box is provided with a radio frequency head antenna of the millimeter wave radar target simulator, and the inner wall of the wave-absorbing box is provided with a wave-absorbing cotton layer.

[0087] The millimeter wave radar target simulator and the wave-absorbing box are used to generate one or more virtual target vehicles in front of the actual vehicle, cooperate with the vehicle running on the chassis dynamometer drum, simulate the vehicles or pedestrians in front of the vehicle on the actual road surface, and provide the virtual targets for ADAS function testing of the front radar scanning target of the vehicle.

[0088] A chassis dynamometer system is used to provide road load simulation for the actual vehicle.

[0089] A virtual scene simulation system comprises a graphics workstation and a virtual scene modeling module running on the graphics workstation. The virtual scene modeling module can build a variety of complex traffic scene models.

[0090] The test management and automatic test module, the virtual scene modeling module and the test management and automatic test module interact through a TCP / IP network interface; the virtual traffic scene in the traffic scene model is output to a scene display screen through an HDMI video interface, and the dynamic graphics on the scene display screen are calibrated to have visual quality and target object size consistent with the traffic scene under real driving conditions; the scene display screen is placed in front of the vehicle-mounted camera through a gantry and a six-degree-of-freedom mechanical arm to provide dynamic simulation of the visual scene for the vehicle-mounted camera.

[0091] The chassis dynamometer system comprises a chassis dynamometer and a chassis dynamometer controller, four drum supports of the chassis dynamometer lift four wheels of an actual vehicle, the friction between the drum and the tire is equivalent to the driving of the vehicle on the actual road surface, and the driving of the vehicle on the drum is ensured to be non-slip. The main function of the chassis dynamometer system is to provide road load simulation for the vehicle in a laboratory environment, the chassis dynamometer controller controls the rotation of the drum in real time, and the driving resistance is provided for the vehicle according to F = A + B · v + C · v 2 wherein F is the driving resistance, the vehicle speed is v, A represents the resistance independent of the speed, B represents the first-order influence coefficient of the speed, and C represents the second-order influence coefficient of the speed. The driving resistance of the special application scenario can be calculated by the virtual scene simulation system and the vehicle dynamics model and output to the chassis dynamometer controller for execution, so that the acceleration and deceleration driving environment of the vehicle on the chassis dynamometer is consistent with the real road load.

[0092] The virtual target (taking a virtual target vehicle as an example) is displayed on the instrument panel of the host vehicle after being recognized by the front radar of the host vehicle, and the relative distance and speed between the host vehicle and the front vehicle are dynamically displayed on the instrument panel; the host vehicle drives on the drum of the chassis dynamometer and starts the ADAS functions such as ACC, AEB, LDW and LKA, and the distance and speed of the virtual target vehicle in front of the host vehicle are dynamically set, and the automatic driving ADAS function of the vehicle is dynamically verified through the automatic change process of the driving distance and speed of the host vehicle.

[0093] The linear motor and the gantry drive the wave-absorbing box to move left and right in front of the host vehicle, so that the virtual target generated by the radar simulator is always in front of the host vehicle; the normal test of the ACC and AEB functions is ensured.

[0094] When the vehicle drives at high speed on the drum of the chassis dynamometer, it will move left and right due to slight rotation of the steering wheel; when the host vehicle moves left and right on the drum of the chassis dynamometer, the deviation displacement generated by the left and right movement is measured by a laser range finder (also known as a laser radar) arranged on the side of the host vehicle. Figure 1The laser head distance measuring device in the embodiment collects and outputs in real time to the chassis dynamometer controller. The test management and automatic test module obtains the offset displacement through the ADS communication protocol, and controls the linear motor and the six-degree-of-freedom mechanical arm on the gantry to move synchronously in real time, so that the virtual target vehicle is in front of the vehicle during ACC and AEB tests, and the virtual traffic scene in the scene display screen is within the field of view of the vehicle-mounted camera during LDW and LKA tests.

[0095] The test management and automatic test module integrates vehicle automatic driving ADAS dynamic verification algorithm and test start-stop, test monitoring and result analysis, and other test management functions. The actual vehicle motion data (distance, speed, acceleration, etc.) on the chassis dynamometer are obtained through the ADS communication protocol, and the offset displacement is obtained. At the same time, the test management and automatic test module interacts with the millimeter wave radar target simulator, the six-degree-of-freedom mechanical arm, the linear motor and the virtual scene simulation system through the TCP / IP network protocol, controls the motion of the virtual target vehicle in front of the vehicle, the six-degree-of-freedom mechanical arm (hereinafter referred to as the mechanical arm) and the wave-absorbing box in real time, and displays the motion state of the vehicle and the virtual target vehicle in the virtual traffic scene. Figure 1

[0096] Embodiment 2

[0097] The wave-absorbing box is a cube composed of five surfaces, and the opening (box opening) is opposite to the front radar of the vehicle, as shown in FIG. 2. Figure 5 The inner wall of the wave-absorbing box is covered with a wave-absorbing cotton layer, and a plurality of pyramids in the form of regular quadrangular pyramids are arranged in an array on the surface of the wave-absorbing cotton layer, as shown in FIG. 3. Figure 6 The density of the pyramids on the surface of the wave-absorbing cotton layer is 784 per square meter, the bottom surfaces (squares) of adjacent two pyramids are closely connected, the side length of the bottom surface of each pyramid is 3.5 cm, the height of each pyramid is 7.5 cm, and the thickness of the part of the wave-absorbing cotton layer without the pyramids is 2.5 cm, that is, the tip of the pyramid is 10 cm away from the bottom surface of the wave-absorbing cotton layer. The wave-absorbing box is used to shield the interference of the surrounding environment in front of the vehicle. The radio frequency head antenna needs to be in the x direction of the front radar of the vehicle, and the distance between the two needs to be at least 50 cm, so that the front radar receives the radio frequency signal of the millimeter wave radar target simulator stably and accurately. When the beam azimuth angle of the front radar of the vehicle is ±60° and the pitch angle is ±10°, the length of the inner wall of the wave-absorbing box is at least 1735 mm, the width is at least 500 mm, and the height is at least 177 mm. At the same time, the parameters of the pyramids need to reach the above-mentioned set values, so as to ensure that the front radar of the vehicle only detects the virtual target vehicle signal generated by the radar simulator, and is not disturbed by the surrounding environment clutter.

[0098] Figure 4 The radar signal strength received by the millimeter wave radar target simulator is represented by the value of the radar signal strength.

[0099] Embodiment 3 ​

[0100] The automobile automatic driving function dynamic verification method comprises the following steps:

[0101] Step S1, adjust the distance between the front axle and the rear axle of the chassis dynamometer according to the wheelbase size of the test vehicle, so that the centers of the four wheels of the test vehicle are aligned with the centers of the four double shafts of the chassis dynamometer in step S2.

[0102] Step S2, drive the test vehicle to the test station of the chassis dynamometer, and bundle the test vehicle at the trailer hook behind the test vehicle; the test vehicle is also referred to as the vehicle, which is also the actual vehicle.

[0103] Step S3, according to the resistance characteristics of the vehicle such as air resistance, rolling resistance, road resistance and driving mode, set the parameters of road load simulation in the chassis dynamometer controller to ensure that the chassis dynamometer can accurately simulate the road load of the vehicle driving on the actual road.

[0104] Step S4, initialize the linear motor and the rack to make the RF head antenna of the millimeter wave radar target simulator on the back of the wave absorption box on the linear motor directly face the center of the front radar of the vehicle. Ensure that the virtual target vehicle is in front of the vehicle at the beginning of the test.

[0105] Step S5, adjust the position of the laser range finder on the right side of the vehicle to make the red laser point emitted by the laser range finder on the intersection line of the center line of the wheel arch of the vehicle and the vertical axis. Ensure that the laser point emitted by the laser range finder is always on the wheel arch of the vehicle as the vehicle moves left and right on the chassis dynamometer.

[0106] Step S6, turn on the millimeter wave radar target simulator, check whether the frequency of the front radar signal of the vehicle received in the frequency domain graph is stable, and check whether the amplitude of the radar signal in the time domain graph is in the range of-1024-1023 (the value is the quantization value of the strength of the radar signal); if the signal amplitude is not in the above range, the system parameters of the millimeter wave radar target simulator expert interface (see Figure 3 ) need to be adjusted, such as "system delay (m)", "amplitude detection threshold", "radar and tester distance (m)", "receive gain attenuation (dB)", etc., until the signal amplitude is in the range of-1024-1023.

[0107] Step S7, build a traffic test scene in the virtual scene simulation system, which includes static traffic scene models (including roads, road marking lines, traffic signs, traffic lights, buildings, etc.), dynamic traffic participants (including traffic vehicle models, pedestrian models, test vehicle models, etc.); associate the speed and distance of the vehicle on the chassis dynamometer with the test vehicle model in the traffic test scene, so that the motion parameters of the vehicle on the chassis dynamometer are consistent with the test vehicle model in the traffic test scene.

[0108] Step S8, starting the test management and automatic test module, which includes a login interface, a test operation interface and a state display interface; wherein the test operation interface is used for the user to connect the test equipment communication, to drive the equipment operation, to start and stop each test process, to display or hide the state display interface; the state display interface is placed in front of the driver, used to prompt the driver the current test content and the operation of each test step, and to display the real-time speed, acceleration, relative distance and displacement of the vehicle offset from the middle of the chassis dynamometer drum of the virtual target; starting the test management and automatic test module in turn carries out user identity verification, initialization, reads the offset displacement caused by vehicle movement and left and right movement through ADS communication, connects the millimeter wave radar target simulator and the six-degree-of-freedom mechanical arm through TCP / IP communication, sends the motion data of the vehicle and the virtual target to the virtual scene simulation system through UDP communication; only when the above communication and data interaction are normal, the automatic driving function detection test process is started;

[0109] Step S9, recording test data and observing test situation at any time, terminating test in time when abnormality occurs; analyzing test results, adjusting the program of the test management and automatic test module, the corresponding time of vehicle speed and ACC or LDW / LKA test step start on the chassis dynamometer, the speed and distance change frequency of the virtual target generated by the millimeter wave radar target simulator, optimizing the following car following, collision effect, lane line length, turning angle, etc. in the virtual traffic scene, and starting the test again until the ideal test effect is obtained.

[0110] Example 4

[0111] In Example 3, specifically to step S3, the longitudinal resistance received by the automobile during driving includes: rolling resistance F f , air resistance F w , slope resistance F s and acceleration resistance F a , which are collectively referred to as the driving resistance F of the automobile:

[0112] F = F f + F w + F s + F a ;

[0113] The rolling resistance can be expressed as the product of the wheel load and the rolling resistance coefficient, i.e.:

[0114] F f = W·f = mg cos θ·f;

[0115] Wherein, m is the mass of the car, unit is kg; g is the acceleration of gravity; θ is the road slope; f is the rolling resistance coefficient, which is related to the type of road surface, the driving speed and the structure, material, air pressure of the tire, etc. It is estimated according to the empirical formula, and the rolling resistance coefficient on good road surface satisfies the following relationship:

[0116]

[0117] The air resistance is the component force of the air acting force on the driving direction of the car, and its value is proportional to the dynamic pressure of the relative speed of the air flow, that is:

[0118]

[0119] Wherein, C d is the air resistance coefficient, which is 0.2-0.4; ρ is the air density, and ρ=1.2258N·s 2 / m 4 ; u r is the relative speed of the vehicle relative to the air, which is the driving speed v of the car in no wind, unit is m / s; A f is the windward area of the car, unit is m 2 , that is, the projection area of the car in the driving direction.

[0120] When the driving speed of the car is counted in km / h, the air resistance can be expressed as:

[0121]

[0122] The slope resistance is the component force of the gravity along the road surface when the car drives on the uphill or downhill road, which can be expressed as: F s =mg·sinθ.

[0123] The acceleration resistance is the inertial force of the mass acceleration motion when the car accelerates, and the car acceleration resistance is expressed as: F a =m·a; wherein, a is the acceleration of the car driving, unit is m / s 2 .

[0124] According to the above analysis, the resistance of the car driving on the actual road surface is:

[0125]

[0126] The first two terms of the above formula are related to the zero power, the first power and the second power of the speed v, which are respectively represented by A, which is the resistance independent of speed, unit is N; B is the first influence coefficient of speed, unit is N / (km / h); C is the second influence coefficient of speed, unit is N / (km / h) 2 ; then the driving resistance of the car can be simply written as:

[0127] F = A + Bv + Cv 2 + mg sin θ + m a

[0128] If the car is running at a constant speed on a horizontal road, the values of the slope resistance and the acceleration resistance are zero, and the running resistance of the car is:

[0129] F = A + Bv + Cv 2 .

[0130] The final formula for calculating the running resistance of the car is simple in form, and for a certain car model, after determining the three constants A, B and C through relevant tests on a chassis dynamometer, the running resistance of the car can be quickly obtained by inputting the running speed, which is very practical.

[0131] Example 5

[0132] In Example 3, in detail to step S8, the test procedures are as follows:

[0133] Step S81, full-speed domain constant-speed cruise test: the driver starts the car, accelerates to 25 km / h by lightly pressing the accelerator, releases the accelerator and turns on the vehicle ACC, changes the speed from the default value 30 to 40, and observes whether the vehicle speed immediately increases from 25 km / h to 40 km / h at a constant speed and can be maintained for more than 5 seconds; then changes the ACC setting value (decreases by 10 and then increases by 10), and observes whether the vehicle speed immediately increases and decreases following the ACC setting value;

[0134] This step is mainly used to test whether the vehicle ACC function can be normally started, and whether the vehicle can accelerate or decelerate at the set ACC speed when the accelerator and brake of the vehicle are released in the scene where there is no other vehicle or pedestrian in front of the vehicle.

[0135] Step S82, ACC deceleration test: set the speed of the virtual target front vehicle to 30 km / h (lower than the vehicle ACC speed 40 km / h), observe whether the front vehicle is displayed on the vehicle instrument panel and the distance from far to near, and whether the vehicle speed decreases from 40 km / h to 30 km / h at a constant speed and is maintained;

[0136] This step is mainly used to test whether the vehicle can automatically decelerate to the same speed as the target vehicle in the scene where the ACC is started and the target vehicle appears in front of the vehicle.

[0137] Step S83, ACC acceleration test: set the speed of the virtual target front vehicle to 35 km / h, observe whether the vehicle speed increases from 30 km / h to 35 km / h at a constant speed and is maintained; then set the speed of the virtual target front vehicle to 50 km / h (higher than the vehicle ACC speed 40 km / h), observe whether the vehicle speed returns to 40 km / h at a constant speed and is maintained, and does not continue to increase to 50 km / h;

[0138] This step is mainly used to test whether the host vehicle can follow the acceleration of the target vehicle until the host vehicle reaches the set ACC speed when the host vehicle is started with ACC and the target vehicle appears in front at the same speed.

[0139] Step S84, ACC parking and automatic starting test: gradually reduce the speed of the virtual target front vehicle to 0, and observe whether the front vehicle gradually approaches on the host vehicle instrument panel and whether the speed of the host vehicle gradually decreases until it stops; set the speed of the virtual target front vehicle from 0 to gradually increase to 30 km / h, and observe whether the front vehicle gradually moves away on the host vehicle instrument panel and whether the host vehicle gradually accelerates until the speed stabilizes at 30 km / h.

[0140] This step is mainly used to test whether the host vehicle can follow the acceleration of the target vehicle until the host vehicle reaches the set ACC speed when the host vehicle is started with ACC and the target vehicle appears in front at the same speed.

[0141] Step S85, LDW and LKA test: turn on the LDW and LKA functions of the host vehicle, and observe whether there is an identification of the function being turned on on the host vehicle instrument panel; the host vehicle travels at a constant speed, enters the road with a curve in the virtual traffic scene, and releases the steering wheel at the curve. Observe whether there is a sound and light prompt for lane deviation warning, and whether the host vehicle travels in the virtual traffic scene without exceeding the lane line by 0.4m and the steering wheel can automatically correct the deviation to return to the center of the lane.

[0142] This step is mainly used to test whether the host vehicle can appear warning and automatically correct deviation to keep within the lane line when it deviates from the lane line in the scenario where the LDW and LKA are turned on.

[0143] The above five tests are the accurate and complete verification process of the ACC, LDW and LKA functions. If each step of the test is passed, it means that the ADAS function of the vehicle is good, otherwise, the ADAS function of the vehicle is abnormal.

[0144] In the above embodiment, the virtual target vehicle generated by the millimeter wave radar target simulator and the wave-absorbing box shielding the front obstacle of the vehicle are the prerequisites for the implementation of the present application.

[0145] In the present application, the wave-absorbing box is used to shield various test equipment around the actual vehicle in the test room scene, to prevent these devices from being recognized by the front radar of the vehicle, so that the front radar of the vehicle only recognizes the virtual target vehicle generated by the millimeter wave radar simulator during testing.

[0146] If the wave-absorbing box is not used to shield the front test equipment of the vehicle, or is not completely shielded, then after the vehicle is driven, the front of the host vehicle (the black car in the middle, i.e. the rear one) on the instrument panel will appear an obstacle (displayed as a white car, see Figure 7 ​Figure 7 the middle (or the front) vehicle.

[0147] If the wave-absorbing box completely shields the test equipment in front of the vehicle, there will be no obstacle in front of the vehicle on the instrument panel after the vehicle drives, as shown in Figure 8 .

[0148] After the wave-absorbing box completely shields the test equipment in front of the vehicle, and the millimeter wave radar target simulator generates a virtual target vehicle, the vehicle drives on the chassis dynamometer, and the state of normally starting the ACC and setting the ACC speed is as shown in Figure 9 , the green vehicle and the instrument sign in the upper right of the figure indicate that the ACC function of the vehicle is started and is working, and the "MAX 30" with a circle in the upper left of the figure indicates the set ACC speed, and the vehicle can be automatically driven to a maximum speed of 30 km / h. The speed of the virtual target vehicle is 24 km / h, and the vehicle also accelerates to 24 km / h to follow the virtual target vehicle.

[0149] If the wave-absorbing box does not completely shield the test equipment in front of the vehicle to start the ACC, or an obstacle suddenly appears in front of the vehicle during the ACC test as above, the vehicle will abnormally exit the ACC and automatically decelerate and brake, as shown in Figure 10 , and such a situation should be avoided as much as possible during the test.

[0150] Only the wave-absorbing cotton and the radio frequency head antenna can face the direction of the vehicle front radar, and if the radio frequency head body, the millimeter wave radar target simulator host or other equipment and cables also appear in front of the vehicle front radar, these objects will be identified as obstacles, so that the ACC function cannot be started. In addition, the virtual target vehicle in front of the vehicle is required to be in the front of the vehicle during the ACC function test, that is, the radio frequency head antenna needs to be in the front of the vehicle front radar, therefore, a linear motor is used to drive the wave-absorbing box to move in the ACC test in the present application.

[0151] If an arc-shaped plate is used instead of the wave-absorbing box in front of the vehicle, the surface of the arc-shaped plate also needs to be pasted with a wave-absorbing cotton layer, and the length and width of the arc-shaped plate are both at least 2.5 m, so that the surrounding test equipment can be completely shielded and not be identified as obstacles by the vehicle front radar. The arc-shaped plate needs to be moved in real time to drive the radio frequency head antenna to face the vehicle front radar during the test, but the area of the 2.5 m*2.5 m arc-shaped plate and the wave-absorbing cotton is very large, and the weight is about 30 kg, which is very difficult to move left and right in real time with the vehicle (heavy weight, large resistance), and the moving precision and instantaneous accuracy cannot be guaranteed; therefore, the scheme of using an arc-shaped plate instead of a wave-absorbing box is not suitable for the present application.

[0152] If the cone in the wave-absorbing cotton layer of the inner wall of the wave-absorbing box is replaced by a short cone, the short cone is also a regular quadrangular pyramid structure like the cone, only the size of the short cone is smaller than that of the cone, for example, the length of the bottom side of the short cone is 1.5 cm, and the height of each short cone is 3.5 cm; the rest is the same as the structure of the wave-absorbing cotton layer; when the wave-absorbing box is used in combination with the millimeter wave radar target simulator, it is found that the wave-absorbing box cannot shield the obstacle.

[0153] The above only describes the preferred embodiments of the present application and is not intended to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An automotive automatic driving function dynamic verification system, characterized in that, The application relates to a millimeter wave radar target simulator, a wave absorbing box, a chassis dynamometer system, a virtual scene simulation system, a test management and automatic test module, a linear motor and a gantry. The millimeter wave radar target simulator is used for generating one or more virtual targets in front of an actual vehicle to simulate a vehicle or a pedestrian in front of the actual vehicle on an actual road surface, and provides the virtual targets for a front radar scanning target to perform ADAS function test. The wave absorbing box is used for shielding surrounding environment interference in front of the actual vehicle. The wave absorbing box is provided with an open box mouth in the front, the front of the box mouth is opposite to the front radar of the actual vehicle, a radio frequency head antenna of the millimeter wave radar target simulator is arranged on the back of the wave absorbing box, and a wave absorbing cotton layer is arranged on the inner wall of the wave absorbing box. The chassis dynamometer system is used for providing road load simulation for the actual vehicle. The virtual scene simulation system comprises a graphics workstation and a virtual scene modeling module running on the graphics workstation. The virtual scene modeling module interacts with the test management and automatic test module through a TCP / IP network interface. The virtual traffic scene in the traffic scene model is output to a scene display screen through an HDMI video interface, the scene display screen is arranged in front of a vehicle-mounted camera through the gantry and the six-degree-of-freedom mechanical arm, and is used for providing dynamic simulation of a visual scene for the vehicle-mounted camera. The chassis dynamometer system comprises a chassis dynamometer and a chassis dynamometer controller. The virtual target is displayed on an instrument panel of the actual vehicle after being recognized by the front radar of the actual vehicle. The linear motor drives the wave absorbing box to move left and right in front of the actual vehicle through the gantry, so that the virtual target generated by the radar simulator is always in front of the actual vehicle. When the actual vehicle moves left and right on the drum of the chassis dynamometer, the offset displacement generated by the left and right movements is collected by a laser range finder arranged on the side of the actual vehicle and is output to the chassis dynamometer controller in real time. The test management and automatic test module obtains the offset displacement through an ADS communication protocol, and controls the linear motor and the six-degree-of-freedom mechanical arm on the gantry to move synchronously in real time. The test management and automatic test module obtains motion data of the actual vehicle running on the chassis dynamometer and the offset displacement through the ADS communication protocol, and simultaneously interacts with the millimeter wave radar target simulator, the six-degree-of-freedom mechanical arm, the linear motor and the virtual scene simulation system through a TCP / IP network protocol, controls the motion of the virtual target in front of the actual vehicle, the six-degree-of-freedom mechanical arm and the wave absorbing box in real time, and displays the motion state of the actual vehicle and the virtual target in the virtual traffic scene. The radio frequency head antenna is arranged along the x direction of the front radar of the actual vehicle, and the distance between the radio frequency head antenna and the front radar of the actual vehicle is at least 50 cm. When the beam azimuth angle of the front radar of the vehicle is ±60°, the pitch angle is ±10°; the length of the inner wall of the wave-absorbing box is at least 1735mm, the width is at least 500mm, and the height is at least 177mm; the surface of the wave-absorbing cotton layer is provided with a plurality of regular quadrangular pyramid-shaped pyramids in an array, the density of the pyramids on the surface of the wave-absorbing cotton layer is 784 per square meter, the bottom surfaces of adjacent two pyramids are closely connected, the bottom surface length of each pyramid is 3.5cm, the height of each pyramid is 7.5cm, and the thickness of the part of the structure in the wave-absorbing cotton layer without the pyramids is 2.5cm. 2.The system of claim 1, wherein: The virtual target includes one or more of a virtual vehicle, a virtual pedestrian, and a virtual animal. 3.The system and method of claim 1, wherein: When tested in ACC and AEB, the virtual target is in front of the vehicle. When tested in LDW and LKA, the virtual traffic scene in the scene display screen is within the field of view of the vehicle-mounted camera.

4. The system of claim 1, wherein: The chassis dynamometer controller controls the rotation of the drum in real time, and the driving resistance is F = A + B · v + C · v 2 The driving resistance is F = A + B · v + C · v, where F is the driving resistance, v is the vehicle speed, A represents the speed-independent resistance, B represents the first-order speed influence coefficient, and C represents the second-order speed influence coefficient.

5. An automotive automatic driving function dynamic verification method, characterized in that, The method comprises the following steps: Step S1: adjusting the distance between the front axle and the rear axle of the chassis dynamometer according to the wheelbase of the test vehicle, so that the centers of the four wheels of the test vehicle are aligned with the centers of the four double shafts of the chassis dynamometer in step S2; Step S2: driving the test vehicle to the test station of the chassis dynamometer and bundling the test vehicle at the trailer hook behind the test vehicle; the test vehicle is referred to as the vehicle; Step S3: setting the parameters of road load simulation in the chassis dynamometer controller, so that the chassis dynamometer simulates the road load of the vehicle driving on the actual road; Step S4: initializing the linear motor and the rack, so that the radio frequency head antenna of the millimeter wave radar target simulator at the back of the wave-absorbing box is directly opposite the center of the front radar of the vehicle; Step S5: adjusting the position of the laser range finder on the right side of the vehicle, so that the red laser point emitted by the laser range finder is on the intersection line of the center line of the wheel arch of the vehicle and the vertical axis; Step S6: turning on the millimeter wave radar target simulator, checking whether the frequency of the received front radar signal of the vehicle in the frequency domain graph is stable, and checking whether the amplitude of the radar signal in the time domain graph changes in the range of -1024-1023; if the signal amplitude is not in the above range, adjustment is needed; Step S7: building a traffic test scene in the virtual scene simulation system, the traffic test scene including a static traffic scene model and a dynamic traffic participant; associating the vehicle speed and the driving distance of the vehicle on the chassis dynamometer with the test vehicle model in the traffic test scene, so that the motion parameters of the vehicle on the chassis dynamometer are consistent with those of the test vehicle model in the traffic test scene. Step S8, starting the test management and automatic test module, which includes a login interface, a test operation interface and a state display interface; wherein the test operation interface is used for the user to connect the test equipment communication, point to drive and automatically drive the equipment operation, start and stop each test process, display or hide the state display interface; the state display interface is placed in front of the driver, used to prompt the driver the current test content and the operation of each test step, and display the real-time speed, acceleration, relative distance and displacement of the vehicle offset from the middle of the chassis dynamometer drum of the virtual target; starting the test management and automatic test module in turn carries out user identity verification, initialization, reads the offset displacement caused by the vehicle movement and left and right movement through ADS communication, connects the millimeter wave radar target simulator and the six-degree-of-freedom mechanical arm through TCP / IP communication, and sends the motion data of the vehicle and the virtual target to the virtual scene simulation system through UDP communication; only when the above communication and data interaction are all normal, the automatic driving function detection test process is started; Step S9, recording test data and observing test situation at any time, terminating test in time when abnormality occurs; analyzing test results, adjusting the corresponding time of vehicle speed at different speeds on the chassis dynamometer and the start of each step of ACC or LDW / LKA test in the program of the test management and automatic test module, the speed and distance change frequency of the virtual target generated by the millimeter wave radar target simulator, optimizing the following, collision effect in the virtual traffic scene, lane length, turning angle, and starting the test again until the ideal test effect is obtained. 6.The method of claim 5, wherein: In step S3, the longitudinal resistance received by the vehicle during running includes a rolling resistance F f , an air resistance F w , a gradient resistance F s , and an acceleration resistance F a , which are collectively referred to as a running resistance F of the vehicle. F = F f + F w + F s + F a ; The rolling resistance can be expressed as the product of the wheel load and the rolling resistance coefficient, that is: F f = W · f = mgcosθ · f; In the formula, m is the mass of the vehicle, kg; g is the acceleration of gravity; θ is the road slope; f is the rolling resistance coefficient, which satisfies the following relationship on good road surface: The air resistance is the component force of the air acting force on the driving direction of the vehicle, and its value is proportional to the dynamic pressure of the air flow relative speed, that is: where C d is the air resistance coefficient, 0.2-0.4; p is the air density, taken as p = 1.2258 N-s / m 2 on the ground 4 ; u r is the relative speed of the vehicle with respect to the air, which is the running speed v of the vehicle in the absence of wind, with the unit of m / s; A f is the frontal area of the vehicle, with the unit of m 2 , i.e. the projection area of the vehicle in the running direction. When the driving speed of the vehicle is km / h, the air resistance can be expressed as: The slope resistance is the component of the gravitational force along the road surface when the vehicle is driving on an uphill or downhill road. It can be expressed as: s = mg · sin θ The acceleration resistance is the inertial force of the mass acceleration movement of the automobile when accelerating. The automobile acceleration resistance is expressed as: F a = m-a; in the formula, a is the acceleration of the automobile when driving, in m / s 2 ; According to the above analysis, the resistance of the vehicle driving on the actual road surface is: Let A represent the speed-independent resistance in N; let B represent the first-order speed influence coefficient in N / (km / h); and let C represent the second-order speed influence coefficient in N / (km / h) 2 ; then the driving resistance of the automobile can be written as F = A + Bv + Cv 2 + mg - sin θ + m - a If the vehicle drives at a constant speed on the horizontal road surface, the values of the slope resistance and the acceleration resistance are zero, and the driving resistance of the vehicle is: F = A + Bv + Cv 2 .

7. The method of claim 5, wherein: In step S7, the static traffic scene model includes one or more of roads, road marking lines, traffic signs, traffic lights and buildings, and the dynamic traffic participants include one or more of traffic vehicle models, pedestrian models and test vehicle models. 8.The method of claim 5, wherein: In step S8, each test process is as follows: Step S81, full-speed domain constant speed cruise test: the driver starts the vehicle, accelerates to 25km / h by lightly stepping on the accelerator, releases the accelerator and turns on the vehicle ACC, changes the speed from the default value 30 to 40, observes whether the speed immediately increases from 25km / h to 40km / h at a constant speed and can be maintained for more than 5s, and then changes the setting value of ACC by reducing 10 and then increasing 10, and observes whether the speed immediately increases and decreases following the setting value of ACC; Step S82, ACC deceleration test: set the front vehicle speed of the virtual target to 30 km / h, which is lower than the vehicle ACC speed 40, and observe whether the front vehicle is displayed on the vehicle instrument panel, and the distance is from far to near, and whether the vehicle speed is uniformly reduced from 40 km / h to 30 km / h and maintained; Step S83, ACC acceleration test: set the front vehicle speed of the virtual target to 35 km / h, and observe whether the vehicle speed is uniformly increased from 30 km / h to 35 km / h and maintained; then set the front vehicle speed of the virtual target to 50 km / h, which is higher than the vehicle ACC speed 40, and observe whether the vehicle speed is uniformly restored to 40 km / h and maintained, and does not continue to increase to 50 km / h; Step S84, ACC parking and automatic starting test: gradually reduce the front vehicle speed of the virtual target until 0, and observe whether the front vehicle on the vehicle instrument panel gradually approaches, and whether the vehicle speed gradually reduces until stopping; set the front vehicle speed of the virtual target from 0 to gradually increase to 30 km / h, and observe whether the front vehicle on the vehicle instrument panel gradually moves away, and whether the vehicle gradually accelerates until the speed is stabilized at 30 km / h; Step S85, LDW and LKA test: turn on the LDW and LKA functions of the vehicle, and observe whether there is an identification of the function being turned on on the vehicle instrument panel; the vehicle uniformly travels, enters the road surface with a curve in the virtual traffic scene, releases the steering wheel at the curve, and observes whether there is an audible and visual warning of lane deviation warning, and whether the vehicle travels in the virtual traffic scene without exceeding the lane line by 0.4 m, and the steering wheel can automatically correct the deviation and return to the center of the lane.

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