EPB rotating hub test control method, system and device and storage medium

Abstract

The invention relates to an EPB rotating hub test control method, system and device and a storage medium, and the method comprises the steps: starting to clamp a vehicle EPB wheel after entering a rotating hub test mode, and obtaining an EPB braking torque applied to the vehicle EPB wheel in real time; in the process of clamping the EPB wheels of the vehicle, the non-EPB wheels of the vehicle are braked through the real-time hydraulic braking torque corresponding to the EPB braking torque, in the rotating hub test, the braking torque of the non-EPB wheels is actively controlled, it is ensured that the vehicle is always in a static state in the EPB clamping process, slippage or yawing caused by uneven braking force distribution is avoided, and the stability of the vehicle is improved. Therefore, the stability of the vehicle in the testing process is ensured, and the safety in the testing process is greatly improved. In addition, the safety coefficient of the whole vehicle is improved, so that the rotating speed of the rotating hub of the EPB wheel in the testing process can be properly improved, and the regulation detection passing rate of the EPB is greatly improved.

Description

Technical Field

[0001] The present application relates to the technical field of vehicle off-line testing, and in particular to an EPB rotary hub test control method, system, device and storage medium. Background Art

[0002] At present, every complete vehicle must pass through the hub table for parking brake force monitoring when it rolls off the assembly line. When the parking brake force is tested, the hub under the axle equipped with EPB (usually the rear wheel) rotates, and the hubs of other wheels (usually the front wheel) do not rotate. Then the EPB caliper is controlled to brake the vehicle, and the resistance torque of the hub table is measured by the sensor. The resistance torque of the hub table = the braking torque of the vehicle, thereby verifying whether the vehicle can pass the test.

[0003] In some related technologies, the following problems may occur during the vehicle rotation test: (1) If the rotation speed of the hub is too low, the wheel speed may be quickly stopped during the EPB clamping process. At this time, the hub and the vehicle tire will slip, which may easily cause sharp corner noise and local tire wear.

[0004] (2) If the rotating hub speed is too high, during the EPB clamping process, the clamping forces of the left and right tires may have torque deviations and torque phase deviations, resulting in dangerous conditions such as the vehicle swaying laterally or sliding off the rotating hub, affecting the safety of the test process and the inspection pass rate. Summary of the invention

[0005] The embodiments of the present application provide an EPB hub test control method, system, device and storage medium to solve the problem in the related art that the hub rotation speed is too high, which may easily cause the vehicle to swing sideways or slip from the hub platform, thus affecting the detection pass rate.

[0006] In a first aspect, an EPB hub test control method is provided, comprising: When the wheel is spinning at high speed and the vehicle speed is zero, it enters the hub test mode; After entering the rotating hub test mode, the vehicle EPB wheel begins to be clamped, and the EPB braking torque applied to the vehicle EPB wheel is obtained in real time; During the process of clamping the EPB wheel of the vehicle, the non-EPB wheel of the vehicle is braked simultaneously with the hydraulic braking torque corresponding to the real-time EPB braking torque.

[0007] In some embodiments, before clamping the EPB wheels of the vehicle, a target hydraulic braking torque is applied to the non-EPB wheels of the vehicle; the target hydraulic braking torque is greater than the parking brake force limit and less than the maximum bearing torque of the hub.

[0008] In some embodiments, during the process of clamping the EPB wheel of the vehicle, the hydraulic braking torque is controlled to increase at a first slope, and the EPB braking torque is controlled to increase at a second slope; The first slope is greater than the second slope, and a difference between the first slope and the second slope is within a design range.

[0009] In some embodiments, obtaining the real-time hydraulic braking torque corresponding to the EPB braking torque includes the following steps: Using the real-time value of the EPB braking torque as a basic value; Acquire the real-time hub speed and tire slip rate corresponding to the EPB braking torque; then compensate the base value based on the hub speed and tire slip rate to obtain a target value; The target value is used as the hydraulic braking torque.

[0010] In some embodiments, the process of clamping the EPB wheel of the vehicle further includes the following steps: Obtain the real-time yaw rate of the vehicle and then compare it with the designed threshold; When the real-time speed of the yaw angle is greater than the design threshold, it indicates that there is a yaw risk, and at the same time the hydraulic braking torque is controlled to increase according to the preset increment at the current moment; the preset increment is 8-15% of the hydraulic braking torque corresponding to the EPB braking torque at the current moment.

[0011] In some embodiments, when the control hydraulic braking torque is increased by a preset increment, if the real-time speed of the yaw angle is still greater than the design threshold, the control EPB braking torque is also increased by the preset increment; When the hydraulic braking torque is controlled to be increased according to the preset increment at the current moment, and the yaw angle real-time speed gradually decreases to below the design threshold, the hydraulic braking torque is controlled to be gradually released by the preset increment.

[0012] In some embodiments, when the EPB braking torque is controlled to increase by the preset increment or when the hydraulic braking torque is controlled to increase by the preset increment at the current moment, if the real-time speed of the yaw angle is still greater than the design threshold, the hub platform is controlled to shut down and all braking systems of the vehicle are locked.

[0013] In a second aspect, an EPB hub test control system is provided, the EPB hub test control system comprising: An EPB controller is used to enter a hub test mode when the wheel rotates at a high speed and the vehicle speed is zero; and after entering the hub test mode, start clamping the vehicle EPB wheel and obtain the EPB braking torque applied to the vehicle EPB wheel in real time; An ESC controller, which is connected to the EPB controller via a CAN bus signal and receives the EPB braking torque; The compensation module is used to calculate the corresponding hydraulic braking torque according to the real-time EPB braking torque during the process of clamping the EPB wheel of the vehicle; and then control the ESC controller to brake the non-EPB wheel of the vehicle with the hydraulic braking torque.

[0014] In a third aspect, an EPB hub test control device is provided, comprising a processor, a memory, and an EPB hub test control program stored in the memory and executable by the processor, wherein when the EPB hub test control program is executed by the processor, the steps of the above-mentioned EPB hub test control method are implemented.

[0015] In a fourth aspect, a computer-readable storage medium is provided, on which an EPB hub test control program is stored, wherein when the EPB hub test control program is executed by a processor, the steps of the above-mentioned EPB hub test control method are implemented.

[0016] The beneficial effects of the technical solution provided by this application include: The embodiments of the present application provide an EPB rotating hub test control method, system, device and storage medium. After entering the rotating hub test mode, the vehicle's EPB wheel begins to be clamped, and the EPB braking torque applied to the vehicle's EPB wheel is obtained in real time; in the process of clamping the vehicle's EPB wheel, the vehicle's non-EPB wheels are braked with a hydraulic braking torque corresponding to the real-time EPB braking torque. In the rotating hub test, the above steps actively control the braking torque of the non-EPB wheels to ensure that the vehicle is always in a stationary state during the EPB clamping process, avoiding slip or yaw caused by uneven distribution of braking force, thereby ensuring vehicle stability during the test and greatly improving safety during the test; in addition, the safety factor of the entire vehicle is improved, so the rotating hub speed of the EPB wheel during the test can be appropriately increased, thereby greatly improving the regulatory inspection pass rate of EPB. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 The contact between the EPB wheel and the non-EPB and the rotating hub of the vehicle on the rotating hub test platform provided in the related art; Figure 2 A general flow chart of the hub test control method provided in an embodiment of the present application; Figure 3 A control flow chart for suppressing yaw provided in an embodiment of the present application. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0020] According to GB 7258-2017 Technical Conditions for Safe Operation of Motor Vehicles, when using a bench test to inspect braking performance, the total parking brake force should be no less than 20% of the vehicle weight under test (no less than 15% for vehicles with a total mass less than 1.2 times the curb weight). Therefore, each vehicle assembly line vehicle of a vehicle manufacturer must be monitored for parking brake force on a rotating hub bench. This article only focuses on the parking brake system of EPB driving.

[0021] The following problems may occur during the vehicle rotation test: (1) If the rotation speed of the hub is too low, the wheel speed may be quickly stopped during the EPB clamping process. At this time, the hub and the vehicle tire will slip, which may easily cause sharp corner noise and local tire wear.

[0022] (2) If the rotating hub speed is too high, during the EPB clamping process, the clamping force of the left and right tires will have torque deviation and torque phase deviation, resulting in dangerous conditions such as lateral swing of the vehicle or slipping off the rotating hub, affecting the safety of the test process and the inspection pass rate. Note: Among them, the reasons for the deviation in the braking torque of the left and right wheels are: the transmission efficiency of each EPB caliper and the friction coefficient of the caliper friction plate cannot be achieved consistently, which results in different braking torques of the left and right tires.

[0023] Reason for torque phase deviation: The back electromotive force at the moment the EPB caliper is started is large. In order to avoid impact on the entire vehicle network, the left and right EPBs are generally started at staggered times (staggered by about 20 to 60ms), so there is a phase difference in the braking torque of the left and right wheels.

[0024] There are also a few key points that need to be clarified: (1) The function of the EPB system (Electronic Parking Brake System), which is usually used for parking brakes, and electronically controls the clamping of the rear wheel calipers. The rotary test bench is used to simulate vehicle driving conditions and test vehicle performance, such as braking and power systems. The vehicle tires are placed on the rotary hub, and the rotary hub rotates to simulate the road surface.

[0025] (2) The reason for dangerous operating conditions such as vehicle swaying sideways or sliding off the hub is that when the EPB caliper clamps the rear wheel (assuming that the EPB acts on the rear wheel), the front wheel may not be braked, resulting in uneven distribution of braking force, and the vehicle may sway or slide on the hub.

[0026] (3) The rotating hub test bench simulates vehicle driving conditions and is used to test braking performance, power output, etc. The vehicle tires are placed on the rotating hub, but the vehicle body remains stationary. Potential risks: If the EPB only applies braking force to a specific wheel (usually the rear wheel) while other wheels (such as the front wheel) have no braking force, it will cause swaying or slipping; Yaw refers to the rotation of the vehicle around the vertical axis, while slip refers to the relative movement between the tire and the hub; yaw moment imbalance refers to the uneven braking force between the front and rear axles, and the vehicle may rotate (yaw) around the vertical axis. Slip risk means: the relative sliding between the tire and the hub due to insufficient friction affects the test accuracy and equipment safety.

[0027] (4) The front wheels are non-EPB wheels, and the ESC system needs to apply hydraulic braking force to these front wheels. This application does not exclude the vehicle configuration of front-wheel EPB, but rear-wheel EPB is more common. See Figure 1 , where the rear wheel is an EPB wheel and the front wheel is a non-EPB wheel. During the test, the hub in contact with the EPB rear wheel rotates.

[0028] See also Figure 2 In the first aspect, the present application proposes an EPB hub test control method for the above problems, which comprises the following steps: Step 100, when the wheels rotate at high speed and the vehicle speed is zero, the hub test mode is entered; that is, the trigger condition is that the EPB recognizes that the vehicle is in the hub test mode through a sensor or a diagnostic signal (such as detecting that the wheels rotate at high speed and the vehicle speed is zero, the vehicle speed being zero means that the vehicle body does not move on the test platform, and only the vehicle EPB wheel rotates with the hub); Step 200: After entering the rotating hub test mode, the EPB wheel of the vehicle begins to be clamped, and the EPB braking torque applied to the EPB wheel of the vehicle is obtained in real time; the EPB caliper is clamped to apply the parking braking force to the rear wheel, simulating the test under the actual parking condition; Step 300: While clamping the EPB wheel of the vehicle, the non-EPB wheel of the vehicle is braked with the hydraulic braking torque corresponding to the real-time EPB braking torque. That is, the ESC applies precise braking force to the front wheel through the hydraulic system to offset the imbalance caused by the unilateral braking of the EPB, balance the braking force of the non-EPB wheel not covered by the EPB, and prevent swaying and slipping.

[0029] Through the above steps, the braking torque of the non-EPB wheel is actively controlled to ensure that the vehicle is always stationary during the EPB clamping process, avoiding slip or yaw caused by uneven distribution of braking force, thereby ensuring the stability of the vehicle during the test and greatly improving the safety during the test; in addition, the safety factor of the whole vehicle is improved, so the hub speed of the EPB wheel during the test can be appropriately increased, thereby greatly improving the regulatory inspection pass rate of EPB.

[0030] It should be understood that the EPB controller and the ESC controller require signal coordination and timing synchronization. The EPB clamping command and the non-EPB wheel braking command must be strictly synchronized, and the timing consistency is ensured through the CAN signal between the controllers (such as 0.1ms level timestamp). The EPB controller sends instructions to the ESC to inform the current EPB braking torque, and then calculates the braking force of the non-EPB wheel; the EPB and ESC transmit braking torque, wheel speed and other data through the CAN bus. The above process is a dynamic process. By acquiring the EPB braking torque applied to the vehicle's EPB wheel in real time, applying the hydraulic braking torque synchronously in real time, and dynamically adjusting the hydraulic braking torque, the vehicle can achieve a dynamic balance of the braking torque in the rotating hub test and adapt to different test conditions.

[0031] That is, yaw stability control: by balancing the braking force of the front and rear axles, the rotational moment around the center of the vehicle is eliminated to prevent the body from deflecting.

[0032] Slip prevention: Regulated hydraulic braking torque ensures effective friction between all tires and the hub to prevent slipping.

[0033] Of course, the above control method can also be applied in the following test scenarios, such as braking performance test: verifying the effectiveness of the EPB working in coordination with the service brake system.

[0034] Powertrain testing: Avoid drive wheel slip during high torque output.

[0035] Four-wheel drive system test: coordinate multi-axis braking force to simulate stability under complex road conditions.

[0036] In some preferred embodiments, dynamic imbalance may occur in the early stage of EPB clamping. To solve this problem, the following settings are provided: Step 200 also includes the following steps: before clamping the EPB wheel of the vehicle, applying a target hydraulic braking torque to the non-EPB wheel of the vehicle; the target hydraulic braking torque is greater than the parking brake force limit and less than the maximum bearing torque of the hub.

[0037] The above steps achieve early intervention braking, and the ESC system applies braking force to the non-EPB wheels in advance before the EPB begins to clamp. The basic braking force can be established in advance to offset the dynamic imbalance that may occur in the early stage of EPB clamping, ensuring that the braking force of the non-EPB wheels is sufficient to stabilize the vehicle alone, even if the EPB braking force is not fully effective. The braking force of the non-EPB wheels must exceed the parking brake force limit specified in GB7258 (for example: the parking brake force must be ≥ 20% of the total vehicle mass).

[0038] Furthermore, the above steps are aimed at the case where the vehicle deflects due to excessive braking force on one side. During the test, the large difference in braking force between different axles can also cause instability. The above axles refer to the front and rear axles. The following settings are used to address this problem: In the process of clamping the EPB wheel of the vehicle, the hydraulic braking torque is controlled to increase at a first slope, and the EPB braking torque is controlled to increase at a second slope; The first slope is greater than the second slope, and a difference between the first slope and the second slope is within a designed range.

[0039] In this embodiment, the design of the first slope and the second slope realizes the torque growth slope control, that is, the braking torque growth rate of the non-EPB wheel must be faster than the growth rate of the EPB clamping force. Through the high dynamic response characteristics of the ESC hydraulic system (such as high-speed solenoid valve adjustment), the braking force can be rapidly linearly increased (for example: the first slope is set to 1.2 to 1.5 times the second slope). Avoid instantaneous torque imbalance caused by excessive difference in the growth rate of the braking force of the front and rear axles during the EPB clamping process.

[0040] In addition, in this embodiment, the slope matching accuracy also needs to be guaranteed to ensure that the braking force curves of ESC and EPB are strictly matched. The calibration method is: calibrate the braking force slope parameters through bench tests, and establish a lookup table mapping in combination with vehicle mass, wheelbase and other parameters.

[0041] In some preferred embodiments, how to calculate the hydraulic braking torque to compensate for the EPB braking torque and ensure the balance of the front and rear axle braking forces has the following settings: Acquiring the hydraulic braking torque corresponding to the real-time EPB braking torque includes the following steps: The real-time EPB braking torque value is used as the basic value; Acquire the hub speed and tire slip rate corresponding to the real-time EPB braking torque; then compensate the base value based on the hub speed and tire slip rate to obtain the target value; The target value is taken as the hydraulic braking torque.

[0042] The above is achieved by taking into account factors such as axle load transfer and friction coefficient based on the vehicle dynamics model to ensure the accuracy of the compensation torque; based on the feedback of the hub speed and tire slip rate, the non-EPB wheel braking force is fine-tuned in real time to ensure the dynamic balance of the total braking torque and the hub driving torque.

[0043] In this application, there are also the following problems: Over-braking risk: excessive braking force of the non-EPB wheel may cause hub overload or abnormal tire wear. The solution is to set a protection mechanism, that is, set an upper limit for braking force (such as not exceeding 80% of the maximum load torque of the hub), and monitor it in real time through a pressure sensor.

[0044] In some preferred embodiments, due to the deviation in the braking torque of the left and right wheels: the transmission efficiency of each EPB caliper and the friction coefficient of the caliper friction plate cannot be consistent, resulting in different braking torques of the left and right tires.

[0045] And due to the reason of torque phase deviation: the back electromotive force at the moment of EPB caliper startup is large. In order to avoid impact on the entire vehicle network, the left and right EPBs are generally started at staggered times (staggered by about 20~60ms), so there is a phase in the braking torque of the left and right wheels.

[0046] After controlling the non-EPB wheel braking force to compensate for the EPB wheel braking force, there is still a risk of yaw. To ensure safety, there are also the following settings: refer to Figure 3 In the process of clamping the vehicle EPB wheel, the following steps are also included: Obtain the real-time yaw rate of the vehicle and then compare it with the designed threshold; When the real-time speed of the yaw angle is greater than the design threshold, it indicates that there is a yaw risk, and at the same time the hydraulic braking torque is controlled to increase according to the preset increment at the current moment; the preset increment is 8-15% of the hydraulic braking torque corresponding to the EPB braking torque at the current moment.

[0047] In this embodiment, yaw rate monitoring and intervention are implemented. The yaw rate threshold in the monitoring parameters is set to 0.5° / s (the specific value needs to be calibrated according to parameters such as the vehicle's center of mass height and wheelbase). The yaw rate signal is obtained through the ESC's built-in inertial measurement unit (IMU) or an independent gyroscope. The trigger condition is: the yaw rate continues to exceed the threshold (for example: for more than 100ms). The logic of intervention is: Level 1 response: The EPB controller sends an emergency boost command to the ESC via the CAN bus, requiring the non-EPB wheel braking torque to be increased by a preset increment (such as 10% of the current value).

[0048] Furthermore, when the control hydraulic braking torque is increased by a preset increment, if the real-time speed of the yaw angle is still greater than the design threshold, the control EPB braking torque is also increased by a preset increment; When the hydraulic braking torque is controlled to increase by the preset increment at the current moment, and the yaw angular velocity gradually decreases to below the design threshold, the hydraulic braking torque is controlled to gradually release the preset increment. In this embodiment, a secondary response is achieved. That is, if the yaw angular velocity does not converge, the EPB clamping force is triggered to increase synchronously, forming a joint braking of the front and rear axles. Exit condition: After the yaw angular velocity falls below the threshold and stabilizes for 200ms, the additional braking force is gradually released.

[0049] Among them, the preset increment is dynamic and different in different situations. The preset increment is proportional to the yaw rate deviation value. This relationship needs to be determined through actual vehicle calibration. I will not introduce it in detail here because each actual vehicle has different parameters and weight. Of course, in order to avoid frequent fluctuations in braking force, hysteresis control can be introduced, which is an existing technology.

[0050] Furthermore, if the communication fails, the ESC compensation may fail and the ESC may not respond to the EPB's request for force increase. In this case, redundancy protection is required, so the following settings are made: When the EPB braking torque is increased by a preset increment or when the hydraulic braking torque is increased by a preset increment at the current moment, and the real-time yaw angle speed is still greater than the design threshold, the rotary hub platform is controlled to shut down and all the vehicle's braking systems are locked. That is, the EPB can start an independent clamping force increase (limited by the maximum clamping force of the mechanical structure), triggering the rotary hub shutdown protocol and locking all braking systems.

[0051] To implement this test, you need to pay attention to the following points: Basic parameter calibration: including vehicle mass distribution, tire-hub friction coefficient, EPB / ESC response delay, etc.

[0052] Threshold calibration: By injecting yaw disturbance (such as unilateral hub acceleration), the critical value of the yaw angular velocity threshold is determined.

[0053] Verification of special scenarios: Extreme working condition testing, simulating failure modes such as EPB clamping delay and ESC hydraulic failure, to verify the robustness of the protection strategy. Long-term testing, verifying the stability of the braking force compensation strategy in continuous testing (such as avoiding overheating of the hydraulic system).

[0054] For the determination that the vehicle is in a stable state or static holding, the displacement of the vehicle on the hub must be ≤1mm (measured by a laser displacement sensor).

[0055] The above test strategy settings, through preloading of non-EPB wheel braking torque, dynamic compensation of non-EPB wheel braking torque, and closed-loop safety protection based on yaw angular velocity, achieve zero displacement constraint of the vehicle in the rotating hub test; millisecond-level intervention in the yaw instability trend; and dual compatibility with regulatory requirements (GB 7258) and equipment safety limits. This strategy embodies the deep integration of multi-system collaborative control and fault-tolerant design, and provides a standardized solution for high-precision vehicle testing.

[0056] In the second aspect, the present application also proposes an EPB hub test control system, the EPB hub test control system comprising: An EPB controller is used to enter a hub test mode when the wheel rotates at a high speed and the vehicle speed is zero; and after entering the hub test mode, start clamping the vehicle EPB wheel and obtain the EPB braking torque applied to the vehicle EPB wheel in real time; An ESC controller is connected to an EPB controller via a CAN bus signal and receives an EPB braking torque; The compensation module is used to calculate the corresponding hydraulic braking torque according to the real-time EPB braking torque during the process of clamping the EPB wheel of the vehicle; and then control the ESC controller to brake the non-EPB wheel of the vehicle with the hydraulic braking torque.

[0057] Among them, the functional implementation of each of the above-mentioned module controllers corresponds to the various steps in the above-mentioned EPB hub test control method embodiment, and its functions and implementation processes will not be repeated here one by one.

[0058] In a third aspect, an embodiment of the present application provides an EPB hub test control device, which may be a personal computer (PC), a laptop computer, a server, a CPU, a host computer, or other device with data processing capabilities.

[0059] In the embodiment of the present application, the EPB hub test control device may include a processor, a memory, a communication interface and a communication bus.

[0060] The communication bus may be of any type and is used to interconnect the processor, the memory, and the communication interface.

[0061] The communication interface includes input / output (I / O) interface, physical interface and logical interface, etc., which are used to realize the interconnection of devices inside the EPB hub test control device, and the interface used to realize the interconnection between the EPB hub test control device and other devices (such as other computing devices or user devices). The physical interface can be an Ethernet interface, a fiber optic interface, an ATM interface, etc.; the user device can be a display, a keyboard, etc.

[0062] The memory can be various types of storage media, such as random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), flash memory, optical storage, hard disk, programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), etc.

[0063] The processor may be a general-purpose processor, and the general-purpose processor may call the EPB hub test control program stored in the memory and execute the EPB hub test control method provided in the embodiment of the present application. For example, the general-purpose processor may be a central processing unit (CPU). The method executed when the EPB hub test control program is called may refer to the various embodiments of the EPB hub test control method of the present application, and will not be described in detail here.

[0064] In a fourth aspect, an embodiment of the present application also provides a computer-readable storage medium.

[0065] The computer-readable storage medium of the present application stores an EPB hub test control program, wherein when the EPB hub test control program is executed by a processor, the steps of the EPB hub test control method as described above are implemented.

[0066] Among them, the method implemented when the EPB hub test control program is executed can refer to the various embodiments of the EPB hub test control method of the present application, and will not be repeated here.

[0067] It should be noted that the serial numbers of the above-mentioned embodiments of the present application are only for description and do not represent the advantages or disadvantages of the embodiments.

[0068] The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally includes steps or units that are not listed, or optionally includes other steps or units inherent to these processes, methods, products or devices. The terms "first", "second" and "third" are used to distinguish different objects, etc., and do not represent a sequence, nor do they limit "first", "second" and "third" to different types.

[0069] In the description of the embodiments of the present application, "exemplary", "for example" or "for example" are used to indicate examples, illustrations or descriptions. Any embodiment or design described as "exemplary", "for example" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary", "for example" or "for example" is intended to present related concepts in a specific way.

[0070] In the description of the embodiments of the present application, unless otherwise specified, “ / ” means or, for example, A / B can mean A or B; the “and / or” in the text is merely a description of the association relationship of associated objects, indicating that three relationships may exist, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of the present application, “multiple” refers to two or more than two.

[0071] In some processes described in the embodiments of the present application, multiple operations or steps that appear in a specific order are included, but it should be understood that these operations or steps may not be executed in the order in which they appear in the embodiments of the present application or in parallel, and the sequence number of the operation is only used to distinguish the different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed in sequence or in parallel, and these operations or steps may be combined.

[0072] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, disk, CD) as described above, and includes a number of instructions for a terminal device to execute the methods described in each embodiment of the present application.

[0073] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. An EPB hub test control method, characterized in that: It includes: When the wheel is spinning at high speed and the vehicle speed is zero, it enters the hub test mode; After entering the rotating hub test mode, the vehicle EPB wheel begins to be clamped, and the EPB braking torque applied to the vehicle EPB wheel is obtained in real time; During the process of clamping the EPB wheel of the vehicle, the non-EPB wheel of the vehicle is braked simultaneously with the hydraulic braking torque corresponding to the real-time EPB braking torque.

2. The EPB hub test control method according to claim 1, characterized in that: Before clamping the EPB wheel of the vehicle, a target hydraulic braking torque is applied to the non-EPB wheel of the vehicle; the target hydraulic braking torque is greater than the parking brake force limit and less than the maximum bearing torque of the rotating hub.

3. The EPB hub test control method according to claim 1, characterized in that: In the process of clamping the EPB wheel of the vehicle, controlling the hydraulic braking torque to increase at a first slope, and controlling the EPB braking torque to increase at a second slope; The first slope is greater than the second slope, and a difference between the first slope and the second slope is within a design range.

4. The EPB hub test control method according to claim 1, characterized in that: Acquiring the real-time hydraulic braking torque corresponding to the EPB braking torque includes the following steps: Using the real-time value of the EPB braking torque as a basic value; Acquire the real-time hub speed and tire slip rate corresponding to the EPB braking torque; then compensate the base value based on the hub speed and tire slip rate to obtain a target value; The target value is used as the hydraulic braking torque.

5. The EPB hub test control method according to claim 1, characterized in that: In the process of clamping the vehicle EPB wheel, the following steps are also included: Obtain the real-time yaw rate of the vehicle and then compare it with the designed threshold; When the real-time speed of the yaw angle is greater than the design threshold, it indicates that there is a yaw risk, and at the same time the hydraulic braking torque is controlled to increase according to the preset increment at the current moment; the preset increment is 8-15% of the hydraulic braking torque corresponding to the EPB braking torque at the current moment.

6. The EPB hub test control method according to claim 5, characterized in that: When the control hydraulic braking torque is increased by a preset increment, and the real-time speed of the yaw angle is still greater than the design threshold, the control EPB braking torque is also increased by the preset increment; When the hydraulic braking torque is controlled to be increased according to the preset increment at the current moment, and the yaw angle real-time speed gradually decreases to below the design threshold, the hydraulic braking torque is controlled to be gradually released by the preset increment.

7. The EPB hub test control method according to claim 6, characterized in that: When the EPB braking torque is controlled to increase by the preset increment or when the hydraulic braking torque is controlled to increase by the preset increment at the current moment, if the real-time speed of the yaw angle is still greater than the design threshold, the hub platform is controlled to stop and all braking systems of the vehicle are locked.

8. An EPB hub test control system, characterized in that: The EPB hub test control system includes: An EPB controller is used to enter a hub test mode when the wheel rotates at a high speed and the vehicle speed is zero; and after entering the hub test mode, start clamping the vehicle EPB wheel and obtain the EPB braking torque applied to the vehicle EPB wheel in real time; An ESC controller, which is connected to the EPB controller via a CAN bus signal and receives the EPB braking torque; The compensation module is used to calculate the corresponding hydraulic braking torque according to the real-time EPB braking torque during the process of clamping the EPB wheel of the vehicle; and then control the ESC controller to brake the non-EPB wheel of the vehicle with the hydraulic braking torque.

9. An EPB hub test control device, characterized in that: The EPB hub test control device includes a processor, a memory, and an EPB hub test control program stored in the memory and executable by the processor, wherein when the EPB hub test control program is executed by the processor, the steps of the EPB hub test control method as described in any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores an EPB hub test control program, wherein when the EPB hub test control program is executed by a processor, the steps of the EPB hub test control method according to any one of claims 1 to 7 are implemented.

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