Desktop-level brake-by-wire test platform and test method thereof

Abstract

The invention relates to the related technical field of brake-by-wire testing, in particular to a desktop-level brake-by-wire testing platform and a testing method thereof. The invention discloses a desktop-level brake-by-wire test platform and a test method thereof. The desktop-level brake-by-wire test platform comprises a platform base body, a brake execution assembly, a camera, a laser radar, a sensor assembly and an information processing assembly, the platform base body comprises an aluminum alloy support which is provided with a bottom layer, a middle layer and an upper layer. Bottom baffles are fixedly connected to the bottoms of the inner sides of the aluminum alloy supports, and side baffles are fixedly connected to the side faces of the aluminum alloy supports. Compared with actual equipment, the device is smaller in size, lower in cost and convenient to use in laboratories and research institutions, the brake-by-wire system can be rapidly iterated and optimized, the research and development efficiency is improved, the requirements under different working conditions and tests can be met through modular design and rich functions and interfaces, and the device is suitable for popularization and application. And meanwhile, single visual sensor detection or fusion detection can be selected according to the requirements of a user.

Description

Technical Field

[0001] The present invention relates to the technical field related to brake-by-wire testing, and in particular to a desktop-level brake-by-wire testing platform and a testing method thereof. Background Art

[0002] With the continuous development of science and technology, wire control technology has been widely used in many fields, especially in the automotive industry. Wire control braking technology has become a necessary system for the intelligence of modern automobiles.

[0003] The brake-by-wire system is a braking system controlled by electronic signals. It eliminates the mechanical connection between the brake pedal and the brake. It can transmit the driver's braking intention or the braking request of the intelligent driving controller through electronic signals, thereby controlling the brake actuator to output braking force, thereby achieving precise control of vehicle braking. However, although the brake-by-wire technology has been widely used in the field of vehicle engineering, it is relatively less used in desktop environments.

[0004] At present, most of the wire control brake technology platforms on the market are designed for passenger vehicles or industrial applications. They are complex in structure, bulky in size, expensive, and not suitable for desktop environments. This makes it difficult to effectively demonstrate the advantages and application potential of wire control brake technology in scenarios such as simulation experiments, tests, and teaching demonstrations. At the same time, with the development of automobile intelligence, target detection technology based on cameras and radars has become increasingly mature. Many brands of cars on the market have integrated target detection technology with wire control brake or wire control steering technology to improve driving safety and practicality. Therefore, the development of a desktop-level wire control brake experimental platform control system based on multi-sensor fusion has important practical value and market prospects. Summary of the invention

[0005] The purpose of this patent is to provide a desktop-level brake-by-wire test platform and its test method to solve the existing problem: most of the brake-by-wire technology platforms on the market are designed for passenger vehicles or industrial applications, with complex structures, large volumes, high prices, and are not suitable for desktop environments. This makes it difficult to effectively demonstrate the advantages and application potential of brake-by-wire technology in scenarios such as simulation experiments, tests, and teaching demonstrations.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A desktop-level brake-by-wire test platform, comprising a platform base, a brake actuator component, a camera, a laser radar, a sensor component and an information processing component;

[0008] The platform base comprises an aluminum alloy bracket, which is arranged as a bottom layer, a middle layer and an upper layer; a bottom baffle is fixedly connected to the inner bottom of the aluminum alloy bracket, a side baffle is fixedly connected to the side of the aluminum alloy bracket, and a pedal baffle is fixedly connected to the end face of the aluminum alloy bracket;

[0009] The brake actuator is used to output a corresponding braking torque according to the pedaling force;

[0010] The sensor comprises: a position sensor and a pressure sensor, wherein the position sensor and the pressure sensor are used to collect a test signal;

[0011] The information processing component includes: CAN communication equipment, a host computer, and a control unit. The control unit is located in the middle layer of the aluminum alloy bracket. The camera, laser radar, brake actuator, and sensor are all connected to the control unit through cables. The control unit is connected to the CAN communication equipment, and the CAN communication equipment is connected to the host computer.

[0012] Preferably, the execution drive unit includes a brake pedal, a brake execution motor, a reducer, a gear rack mechanism, a brake master cylinder, a fluid reservoir, a brake caliper, and a brake disc. A fluid reservoir is arranged on the outer side of the brake master cylinder; the brake pedal is movably connected to the aluminum alloy bracket, the brake pedal corresponds to the position of the pedal baffle, the brake disc is arranged at the position outside the side baffle, and the brake caliper is arranged on the side baffle; the brake execution motor is transversely fixed to the middle position of the aluminum alloy bracket through a connecting piece, a motor controller is arranged on the outer side of the brake execution motor, the motor controller is electrically connected to the brake execution motor, the output shaft of the brake execution motor is connected to the reducer, and the output shaft of the reducer is connected to the gear rack mechanism through a coupling; the gear rack mechanism is connected to the brake master cylinder through another coupling;

[0013] A brake oil pipe is arranged inside the aluminum alloy bracket, and the brake oil pipe is connected to the brake caliper and the brake master cylinder respectively. The brake fluid of the brake master cylinder is input to the brake caliper along the brake oil pipe.

[0014] Preferably, the camera and laser radar are both arranged on the front upper layer of the aluminum alloy bracket, and a buzzer and a secondary light tube are arranged on the side baffle; the buzzer and the secondary light tube are both connected to the control unit through cables.

[0015] Preferably, the camera, lidar and brake actuator assembly can all be disassembled and tested individually.

[0016] Preferably, the position sensor includes a pedal position sensor and a rack and pinion position sensor, the pedal position sensor is fixedly connected to an aluminum alloy bracket, the pedal position sensor is located at one side of the brake pedal, the rack and pinion position sensor is fixedly connected to the aluminum alloy bracket, the rack and pinion position sensor is located at one side of the rack and pinion mechanism, and the pressure sensor is fixedly connected to the aluminum alloy bracket, and the pressure sensor is located at the other side of the brake pedal.

[0017] Preferably, it also includes a target detection system, which uses the YOLOvs model to be trained on the KITTI data set, and the user adds the required modules according to actual needs; and uses the PointPillars network framework to build a network model to detect objects in the laser point cloud information.

[0018] Preferably, it also includes an automatic emergency braking system, which grades the distance threshold according to different road conditions and the driving state of the vehicle ahead.

[0019] A test method for a desktop-level brake-by-wire test platform is used for the above-mentioned desktop-level brake-by-wire test platform, and the steps are as follows:

[0020] Step 1: Load the whole vehicle model and the wire control brake model in the host computer, wherein the whole vehicle model includes a tire model, a body model and a suspension model; the wire control brake model includes a brake motor model and a brake actuator motor CAN communication model;

[0021] Step 2: The control unit has built-in target recognition algorithm, sensor signal processing algorithm and brake actuator control algorithm; the brake actuator control algorithm includes different automatic emergency braking control strategies, including laser radar and secondary light warning strategy, fixed deceleration braking strategy and full braking strategy;

[0022] Step 3: Load the model in S into the host computer and reserve a window for adjusting vehicle information parameters;

[0023] Step 4: embed the algorithm in S into the control unit; the control algorithm reserves input and output interfaces for the tester to burn his own control algorithm for verification testing;

[0024] Step 5: The driver inputs the control signal by operating the brake pedal and the upper computer parameter adjustment window;

[0025] Step 6: The signal collected by the pressure sensor is transmitted to the host computer after signal processing by the control unit, so as to input the braking parameters of the vehicle model in the host computer;

[0026] Step 7: The signals collected by the camera, lidar and sensor are processed by the control unit and transmitted to the host computer to collect the test results:

[0027] Step 8: The tester evaluates and modifies the control algorithm based on the input and output data of the host computer.

[0028] The present invention has at least the following beneficial effects:

[0029] 1. Compared with actual equipment, the present invention has a smaller size and lower cost, and is convenient for use in laboratories and research institutions. In addition, the present invention can realize rapid iteration and optimization of the brake-by-wire system, improve research and development efficiency, and the modular design and rich functions and interfaces can meet the needs of different working conditions and tests. At the same time, single visual sensor detection or fusion detection can be selected according to user needs.

[0030] 2. The present invention can also provide a safe environment for users to conveniently conduct experiments, tests, verifications and teaching of brake-by-wire, thus providing strong support for the development of vehicle intelligent technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0033] Figure 2 It is the overall structural front view of the present invention;

[0034] Figure 3 It is a top view of the overall structure of the present invention;

[0035] Figure 4 It is a framework diagram of the control system of the present invention;

[0036] Figure 5 This is a flow chart of the automatic emergency braking system.

[0038] In the figure: 1. Camera; 2. LiDAR; 3. Aluminum alloy bracket; 4. Pedal position sensor; 5. Brake pedal; 6. Pressure sensor; 7. Buzzer; 8. Secondary lamp; 9. Side baffle; 10. Brake caliper; 11. Motor controller; 12. CAN communication equipment; 13. Host computer; 14. Brake actuator motor; 15. Connector; 16. Reducer; 17. Coupling; 18. Rack and pinion mechanism; 19. DC power supply; 20. Brake master cylinder; 21. Fluid reservoir; 22. Brake oil pipe; 23. Control unit; 24. Pedal baffle; 25. Bottom baffle; 26. Rack and pinion position sensor. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0040] Embodiment 1:

[0041] Reference Figure 1 - Figure 2 As shown, a desktop-level wire-controlled brake test platform includes a platform base, a brake execution component, a camera 1, a laser radar 2, a sensor component and an information processing component;

[0042] The platform base includes an aluminum alloy bracket 3, which is arranged as a bottom layer, a middle layer and an upper layer; a bottom baffle 25 is fixedly connected to the inner bottom of the aluminum alloy bracket 3, a side baffle 9 is fixedly connected to the side of the aluminum alloy bracket 3, and a pedal baffle 24 is fixedly connected to the end surface of the aluminum alloy bracket 3;

[0043] A brake actuator component, used to output a corresponding braking torque according to the pedaling force;

[0044] The sensors include: a position sensor and a pressure sensor 6, which are used to collect test signals;

[0045] The information processing components include: CAN communication equipment 12, host computer 13, control unit 23, the control unit 23 is located in the middle layer of the aluminum alloy bracket 3, the camera 1, laser radar 2, brake execution component, and sensor are all connected to the control unit 23 through cables, the control unit 23 is connected to the CAN communication equipment 12, and the CAN communication equipment 12 is connected to the host computer 13.

[0046] Preferably, the execution drive unit includes a brake pedal 5, a brake execution motor 14, a reducer 16, a gear rack mechanism 18, a brake master cylinder 20, a fluid reservoir 21, a brake caliper 10, and a brake disc. The brake master cylinder 20 is provided with a fluid reservoir 21; the brake pedal 5 is movably connected to the aluminum alloy bracket 3, the brake pedal 5 corresponds to the position of the pedal baffle 24, the brake disc is arranged at the position outside the side baffle 9, and the brake caliper 10 is arranged on the side baffle 9; the brake execution motor 14 is transversely fixed to the middle position of the aluminum alloy bracket 3 by a connecting member 15, a motor controller 11 is arranged on the outside of the brake execution motor 14, the motor controller 11 is electrically connected to the brake execution motor 14, the output shaft of the brake execution motor 14 is connected to the reducer 16, and the output shaft of the reducer 16 is connected to the gear rack mechanism 18 through a coupling 17; the gear rack mechanism 18 is connected to the brake master cylinder 20 through another coupling 17;

[0047] A brake oil pipe 22 is disposed inside the aluminum alloy bracket 3 . The brake oil pipe 22 is connected to the brake caliper 10 and the brake master cylinder 20 , respectively. The brake fluid of the brake master cylinder 20 is input to the brake caliper 10 along the brake oil pipe 22 .

[0048] Preferably, the camera 1 and the laser radar 2 are both arranged on the front upper layer of the aluminum alloy bracket 3, and a buzzer 7 and a secondary light tube 8 are arranged on the side baffle 9; the buzzer 7 and the secondary light tube 8 are both connected to the control unit 23 through cables.

[0049] Preferably, the camera 1, the laser radar 2 and the brake actuator assembly can all be disassembled and tested individually.

[0050] Preferably, the position sensor includes a pedal position sensor 4 and a rack and pinion position sensor 26, the pedal position sensor 4 is fixedly connected to the aluminum alloy bracket 3, the pedal position sensor 4 is located at one side of the brake pedal 5, the rack and pinion position sensor 26 is fixedly connected to the aluminum alloy bracket 3, the rack and pinion position sensor 26 is located at one side of the rack and pinion mechanism 18, and the pressure sensor 6 is fixedly connected to the aluminum alloy bracket 3, the pressure sensor 6 is located at the other side of the brake pedal 5.

[0051] Preferably, it also includes a target detection system, which uses the YOLOv5s model to be trained on the KITTI data set, and the user adds the required modules according to actual needs; and uses the PointPillars network framework to build a network model to detect objects in the laser point cloud information.

[0052] Preferably, it also includes an automatic emergency braking system, which grades the distance threshold according to different road conditions and the driving state of the vehicle ahead.

[0053] Environmental information is collected through the laser radar 2 and the camera 1, and the target detection algorithm and the distance measurement algorithm are introduced. The appropriate braking strategy is selected according to the detected target distance information and the emergency braking control strategy based on the safety distance model. The motor controller 11 collects target information, brake pressure signal, gear rack mechanism 18 and brake pedal 5 position information in real time through sensors. After the set control strategy calculation, the brake execution motor 14 drives the gear rack mechanism 18 to push the brake master cylinder 20, so that the brake fluid flows to the brake caliper 10 through the brake oil pipe 22 for braking; at the same time, the control system obtains the ideal braking torque according to the road information, working conditions, vehicle body mass, suspension structure and other parameters set by the host computer 13, combined with the brake pedal 5 position, gear rack mechanism 18 position and brake pressure, and then sends a signal through the CAN communication device 12 to adjust the rotation angle of the brake execution motor 14, so as to achieve precise braking.

[0054] The present invention utilizes visual sensors and brake actuators to operate effectively and efficiently, and realizes that the transmission ratio of the brake system changes in real time according to the vehicle working conditions. The camera 1 performs real-time target detection and can input real-time control and control strategies according to vehicle state parameters and brake pedal 5. It can be replaced and adjusted in real time according to the needs of users, without being limited to adjustable parameters. In terms of volume and weight, the platform has the advantages of miniaturization and lightness, with a small installation space and more convenient use. The modular design can meet more abundant test needs. It can be used for teaching demonstrations and experiments in colleges and universities, and can also be used as equipment for researchers to test algorithms. At the same time, it has better scalability. By adding other modules, such as wire-controlled suspension systems and wire-controlled steering systems, the test field can be extended to directions other than wire-controlled braking.

[0055] Compared with the traditional wire control brake test bench based on real vehicle assembly or components, the present invention is composed of miniaturized, low-cost, widely used components and a control system with strong adaptability, high safety and good maintainability. The present invention is further described below through specific implementation and combined with the accompanying drawings:

[0056] The overall test platform is fixed on the aluminum alloy bracket 3, and the DC power supply 19 is connected to each component through cables for power supply. The upper computer 13 integrates the degree of freedom vehicle model, wire control brake model, transmission ratio control algorithm, initial working condition, road surface information, human-machine interface, etc., and is connected to the CAN communication device 12 through cables. The CAN communication adopts PEAK-System communication equipment and is connected to the control unit 23 (ECU). The control unit 23ECU is installed in the middle layer of the aluminum alloy bracket 3, adopts STM32G431 single-chip microcomputer, and uses FD6299T integrated circuit chip to output three-phase electricity, including encoder interface, DC interface, ADC interface, CAN communication interface, etc. The control unit 23 is embedded with sensor signal processing algorithm, brake actuator control algorithm, target detection algorithm and target ranging algorithm, and is connected to the pedal position sensor 4, gear rack position sensor 26, pressure sensor 6, motor controller 11, camera 1, and laser radar 2 through cables.

[0057] The brake pedal 5 is connected to the pedal position sensor 4, the gear rack position sensor 26 is connected to the gear rack mechanism 18, and the pressure sensor 6 is connected to the brake caliper 10 through a three-way element; during the test, the initial working conditions are first set in the host computer 13, such as vehicle speed, vehicle parameters, information, etc. When the camera 1 and the laser radar 2 obtain the external environment information, the environmental information obtained by the two will be integrated and transmitted to the control unit 23. After the control unit 23 converts the environmental information into a digital signal, it is transmitted to the host computer 13 through the CAN communication device 12. The host computer 13 records the acquired environmental information and the angle value; the control unit 23 ECU has built-in decision-level target detection algorithm, target ranging algorithm and automatic emergency braking control strategy to meet the test requirements under different working conditions. According to the target detection algorithm and ranging algorithm, the control unit 23 will identify the target object and the distance to the platform, and transmit it to the motor controller 11. The motor controller 11 is installed in the middle layer of the host computer 13 and is connected to the brake execution motor 14 through a cable.

[0058] When the motor controller 11 receives a command from the control unit 23, it controls the brake execution motor 14 to output the corresponding rotation angle, and decelerates and increases torque through the reducer 16. The reducer 16 is connected to the gear rack mechanism 18 through the coupling 17, and the gear rack mechanism 18 is connected to the brake master cylinder 20 through another coupling 17. The gear rack mechanism 18 rotates, driving the brake master cylinder 20 to move through the coupling 17, so that the brake fluid generates pressure and flows into the brake oil pipe 22, and is transmitted to the brake caliper 10. The pressure of the brake fluid pushes the brake caliper 10 to rub against the brake disc, thereby generating a braking torque. The brake oil pipe 22 is installed in parallel in the aluminum alloy bracket 3, and the gear rack position sensor 26 is installed in parallel with the gear rack mechanism 18. The gear rack position sensor 26 transmits the displacement analog signal of the gear rack mechanism 18 to the control unit 23 through a cable. The control unit 23 converts the analog signal into a digital signal and transmits it to the host computer 13 through the CAN communication device 12. The host computer 13 calculates the actual braking torque and the ideal braking torque according to the displacement of the gear rack mechanism 18 to form a closed loop through PID control.

[0059] In order to be able to change the target recognition algorithm and the brake actuator control algorithm, the underlying code of the control unit 23 retains the algorithm function interface. The user only needs to compile the algorithm function code and burn it into the control unit 23 to verify the effectiveness and stability of the control algorithm.

[0060] Embodiment 2:

[0061] Based on the above embodiment 1, the test method is disclosed:

[0062] Step 1: Load the whole vehicle model and the wire control brake model in the upper computer 13, wherein the whole vehicle model includes a tire model, a body model and a suspension model; the wire control brake model includes a brake motor model and a brake actuator motor CAN communication model;

[0063] Step 2: The control unit 23 has built-in target recognition algorithm, sensor signal processing algorithm and brake actuator control algorithm; the brake actuator control algorithm includes different automatic emergency braking control strategies, including laser radar 2 and secondary light tube 8 warning strategy, fixed deceleration braking strategy and full braking strategy;

[0064] Step 3: Load the model in S1 into the host computer 13, and reserve a window for adjusting vehicle information parameters;

[0065] Step 4: embed the algorithm in S2 into the control unit 23; the control algorithm reserves input and output interfaces for the tester to burn his own control algorithm for verification testing;

[0066] Step 5: The driver inputs a control signal through the operation of the brake pedal 5 and the parameter adjustment window of the host computer 13;

[0067] Step 6: The signal collected by the pressure sensor 6 is transmitted to the host computer 13 after signal processing by the control unit 23, so as to input the braking parameters of the vehicle model in the host computer 13;

[0068] Step 7: The signals collected by the camera 1, the laser radar 2 and the sensor are processed by the control unit 23 and transmitted to the host computer 13 to collect the test results:

[0069] Step 8: The tester evaluates and modifies the control algorithm based on the input and output data of the host computer 13.

[0070] Embodiment 3:

[0071] Based on the above embodiments 1-2, a target detection system is disclosed:

[0072] The present invention adopts the YOLOv5 algorithm for target recognition, which can predict objects in images through a single forward propagation. Its detection speed fully meets the requirements of real-time detection, and because it has a variety of network models, it can adapt to different hardware platforms and performance requirements.

[0073] The present invention intends to use the YOLOv5s model to train on the KITTI data set. The user can add the required modules according to actual needs. For example, if the focus of detection is small target objects, a small target detection head can be added to the model. After setting the hyperparameters and training parameters of the model, training is performed. The trained model can accurately detect the object in front. Because the picture has no depth information, it can only detect whether there is an object in the image, but cannot obtain the distance and state information between the object and the object. The position of the object in the image is marked by calculation and processing, and the position information of the object in the image is obtained. The internal and external parameters of camera 1 are calibrated by Zhang Youzheng calibration method, and the focal length, distortion parameters and other information of camera 1 are obtained. The pixel coordinates of the object on the image are converted to the coordinates in the camera 1 coordinate system through the internal and external parameters, and the distance between the coordinates of the object in the camera 1 coordinate system and the optical center of camera 1 is calculated. The coordinates in the camera 1 coordinate system are converted to the coordinates in the world coordinate system, and the actual distance of the object from camera 1 is calculated.

[0074] The image coordinate system is composed of the pixel coordinate system (u, v) and the physical coordinate system (x, y). The relationship between them can be expressed in matrix form:

[0075]

[0076] Let the length of a pixel on the x-axis and y-axis be dx and dy.

[0077] The relationship between the camera 1 coordinate system and the image coordinate system can be expressed in matrix form:

[0078]

[0079] X c ,Y c ,Z c is the camera 1 coordinate system, with the optical center at O c , f is the focal length of camera 1, which is equal to the distance between the image center O and the optical center O c The distance between.

[0080] The relationship between the world coordinate system and the camera 1 coordinate system can be expressed in matrix form:

[0081]

[0082] Because the camera 1 is highly sensitive to the light environment, in order to compensate for its shortcomings, the laser radar 2 is added to obtain the three-dimensional information of the object. The present invention uses a deep learning method to train the model. The point cloud dataset in the KITTI dataset is used for training. The laser radar 2 can measure the distance of the object and calculate the three-dimensional point coordinates of the point cloud based on the distance.

[0083] The present invention uses the PointPillars network framework to build a network model to detect objects in laser point cloud information. First, the original three-dimensional point cloud data is converted into a pseudo image to facilitate subsequent network processing. Then a two-dimensional convolutional network is used to extract and fuse the features in the pseudo image above. After a series of upsampling, deconvolution, BN layer and ReLU layer, the features of different scales are spliced ​​and fused through the Concat module. Finally, the predicted bounding box of the object is generated by the detection regression network.

[0084] Similar to the YOLO algorithm, after configuring the network framework, the model is trained using the KITTI 3D target dataset, and finally the model file with the best performance is selected for fusion with the visual algorithm.

[0085] Because camera 1 and lidar 2 have differences in frame rate, detection distance, etc., they need to be synchronized in time and space in advance. First, the spatial coordinate system is aligned to unify the point cloud information of lidar 2 and the image information obtained by camera 1 in terms of dimension. In terms of time synchronization, because the sampling frequency of camera 1 is higher and the sampling frequency of lidar 2 is relatively lower, it is chosen to remove the redundant image frames collected by camera 1 to achieve unification in the time dimension.

[0086] The present invention uses a decision-level fusion algorithm to fuse image information and point cloud information, thereby improving the accuracy of object detection and reducing missed detections. Similarly, the fusion algorithm also relies on deep learning for training. First, the two different data information are fused and preprocessed, and then the preprocessed information is trained through the fusion network, and finally the fusion detection result is output.

[0087] Automatic Emergency Braking System:

[0088] Under different road conditions, cars will encounter different braking scenarios, which are divided into two situations: stationary and moving according to the driving status of the vehicle in front. When the vehicle in front is stationary, the distance threshold for generating a warning is called S1, the distance threshold for requiring slight braking is S2, and the distance threshold for requiring full braking is S3.

[0089] The hierarchical braking strategy of the present invention is shown in the following table:

[0090]

[0091] like Figure 4 As shown, when the car is driving, a certain threshold is reached through calculation of the safety distance model and a corresponding braking strategy is implemented, wherein the third danger level is braking at a set deceleration, and the fourth danger level is directly performing full-force braking after reaching the threshold.

[0092] First, the object in front is judged by sensors such as camera 1 and laser radar 2 to determine whether it is within the specified lane range of the current test bench. If it is, it is regarded as a dangerous target. The safety distance model generates braking thresholds of different danger levels. When the distance between the test bench and the vehicle in front is S>S1, the system does not work; when the distance between the test bench and the vehicle in front is S<S1 and S>S2, the system will control the buzzer 7 and the secondary light tube 8 to work for warning; if the braking distance S continues to decrease, so that S2>S>S3, the system will take a fixed deceleration braking operation; when the distance between the test bench and the vehicle in front is less than the fourth danger level distance threshold, the system will take emergency braking measures and perform full braking to ensure the safety of the driver.

Claims

1. A desktop-level brake-by-wire test platform, characterized by: It includes a platform base, a brake execution component, a camera (1), a laser radar (2), a sensor component and an information processing component; The platform base comprises an aluminum alloy bracket (3), wherein the aluminum alloy bracket (3) is arranged as a bottom layer, a middle layer and an upper layer; a bottom baffle (25) is fixedly connected to the inner bottom of the aluminum alloy bracket (3), a side baffle (9) is fixedly connected to the side of the aluminum alloy bracket (3), and a pedal baffle (24) is fixedly connected to the end surface of the aluminum alloy bracket (3); The brake actuator is used to output a corresponding braking torque according to the pedaling force; The sensor comprises: a position sensor and a pressure sensor (6), wherein the position sensor and the pressure sensor (6) are used to collect a test signal; The information processing component comprises: a CAN communication device (12), a host computer (13), and a control unit (23). The control unit (23) is located at the middle layer of the aluminum alloy bracket (3). The camera (1), the laser radar (2), the brake actuator, and the sensor are all connected to the control unit (23) via cables. The control unit (23) is connected to the CAN communication device (12), and the CAN communication device (12) is connected to the host computer (13).

2. A desktop-level brake-by-wire test platform according to claim 1, characterized in that: The execution drive unit comprises a brake pedal (5), a brake execution motor (14), a speed reducer (16), a gear rack mechanism (18), a brake master cylinder (20), a fluid reservoir (21), a brake caliper (10), and a brake disc, wherein the brake master cylinder (20) is provided with a fluid reservoir (21) on the outside; the brake pedal (5) is movably connected to the aluminum alloy bracket (3), the positions of the brake pedal (5) and the pedal baffle (24) correspond, the brake disc is provided at a position outside the side baffle (9), and the brake caliper (10) is provided on the side baffle (9); The brake actuator motor (14) is transversely fixed to the middle position of the aluminum alloy bracket (3) through a connecting piece (15); a motor controller (11) is arranged on the outer side of the brake actuator motor (14); the motor controller (11) is electrically connected to the brake actuator motor (14); the output shaft of the brake actuator motor (14) is connected to a reducer (16); the output shaft of the reducer (16) is connected to a gear rack mechanism (18) through a coupling (17); the gear rack mechanism (18) is connected to a brake master cylinder (20) through another coupling (17); A brake oil pipe (22) is arranged inside the aluminum alloy bracket (3), and the brake oil pipe (22) is connected to the brake caliper (10) and the brake master cylinder (20) respectively, and the brake fluid of the brake master cylinder (20) is input into the brake caliper (10) along the brake oil pipe (22).

3. A desktop-level brake-by-wire test platform according to claim 1, characterized in that: The camera (1) and the laser radar (2) are both arranged on the front upper layer of the aluminum alloy bracket (3); a buzzer (7) and a secondary light tube (8) are arranged on the side baffle (9); the buzzer (7) and the secondary light tube (8) are both connected to the control unit (23) via cables.

4. The desktop-level wire-controlled brake test platform according to claim 1, characterized in that: The camera (1), laser radar (2) and brake execution assembly can all be disassembled and tested individually.

5. The desktop-level brake-by-wire test platform according to claim 1, characterized in that: The position sensor comprises a pedal position sensor (4) and a gear rack position sensor (26); the pedal position sensor (4) is fixedly connected to the aluminum alloy bracket (3); the pedal position sensor (4) is located at a position on one side of the brake pedal (5); the gear rack position sensor (26) is fixedly connected to the aluminum alloy bracket (3); the gear rack position sensor (26) is located at a position on one side of the gear rack mechanism (18); the pressure sensor (6) is fixedly connected to the aluminum alloy bracket (3); the pressure sensor (6) is located at a position on the other side of the brake pedal (5).

6. The desktop-level brake-by-wire test platform according to claim 1, characterized in that: It also includes a target detection system, which uses the YOLOv5s model to be trained on the KITTI data set, and the user can add the required modules according to actual needs; and uses the PointPillars network framework to build a network model to detect objects in laser point cloud information.

7. The desktop-level brake-by-wire test platform according to claim 1, characterized in that: It also includes an automatic emergency braking system, which grades the distance threshold according to different road conditions and the driving state of the vehicle ahead.

8. A method for testing a desktop-level brake-by-wire test platform, used for a desktop-level brake-by-wire test platform according to any one of claims 1 to 7, characterized in that: Here are the steps: S1: A whole vehicle model and a wire-controlled brake model are installed in a host computer (13), wherein the whole vehicle model includes a tire model, a body model and a suspension model; and the wire-controlled brake model includes a brake motor model and a brake actuator motor CAN communication model; S2: The control unit (23) has a built-in target recognition algorithm, a sensor signal processing algorithm and a brake actuator control algorithm; the brake actuator control algorithm includes different automatic emergency braking control strategies, including a laser radar (2) and a secondary light tube (8) warning strategy, a fixed deceleration braking strategy and a full braking strategy; S3: Load the model in S1 into the host computer (13), and reserve a window for adjusting vehicle information parameters; S4: embedding the algorithm in S2 into the control unit (23); wherein the control algorithm reserves input and output interfaces for the tester to burn his own control algorithm for verification testing; S5: The driver inputs a control signal through the parameter adjustment window of the host computer (13) by operating the brake pedal (5); S6: The signal collected by the pressure sensor (6) is transmitted to the host computer (13) after signal processing by the control unit (23), so as to input the braking parameters of the vehicle model in the host computer (13); S7: The signals collected by the camera (1), the laser radar (2) and the sensor are processed by the control unit (23) and transmitted to the host computer (13) to collect the test results: S8: The tester evaluates and modifies the control algorithm based on the input and output data of the host computer (13).

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