Vehicle brake redundancy method and system, vehicle and readable storage medium

Abstract

The invention discloses a vehicle brake redundancy method and system, a vehicle and a readable medium, and belongs to the technical field of automatic driving. The vehicle braking redundancy method comprises the steps that in response to a valet parking instruction of a target vehicle, a state signal of the target vehicle is monitored; wherein the state signal is used for indicating the state of the autonomous parking system of the target vehicle; acquiring the state of the autonomous parking system based on the state signal; based on the state of the autonomous parking system, whether the target vehicle has a braking redundancy requirement or not is judged; if yes, a preset braking redundancy strategy is executed on the basis of the braking redundancy requirement, so that braking redundancy of the target vehicle is achieved. Brake redundancy can be achieved in the valet parking process, and meanwhile the problems of high cost, heavy weight, complex assembly and the like caused by using an RBU are solved.

Description

Technical Field

[0001] The present application belongs to the field of autonomous driving technology, and specifically relates to a vehicle braking redundancy method, system, vehicle and readable storage medium. Background Art

[0002] During valet parking, a common operating scenario is that after the driver leaves the vehicle, the system performs a long-distance parking task at a speed of about 10kph. In order to ensure safety during parking, the existing technology generally uses a redundant brake unit (Redundant Brake Unit, hereinafter referred to as RBU) to perform redundant backup of the braking system, that is, it is necessary to set up an additional RBU on the vehicle, and it is necessary to design a corresponding brake redundancy strategy based on the RBU. However, on the one hand, in vehicle applications, the RBU unit cost is high and the weight is heavy, which will significantly increase the manufacturing cost and weight burden of the vehicle; on the other hand, when assembling the RBU in the OEM assembly workshop, it is necessary to add 4 additional brake pipes, which makes the vehicle assembly process quite complicated and reduces production efficiency. Summary of the invention

[0003] The purpose of the present application is to provide a vehicle brake redundancy method, system, vehicle and readable storage medium, which can realize brake redundancy in a valet parking system while overcoming the problems of high cost, heavy weight, complex assembly and the like caused by using RBU.

[0004] In order to solve the above technical problems, this application is implemented as follows: In a first aspect, the present application provides a vehicle braking redundancy method, the method comprising: In response to a valet parking instruction of a target vehicle, monitoring a status signal of the target vehicle; wherein the status signal is used to indicate a status of an autonomous parking system of the target vehicle; Based on the status signal, obtain the status of the autonomous parking system; Based on the status of the autonomous parking system, determine whether the target vehicle has a need for brake redundancy; If so, based on the braking redundancy requirement, a preset braking redundancy strategy is executed to achieve braking redundancy of the target vehicle.

[0005] Further, the status signal includes a brake signal, a push rod travel signal, a deceleration signal and a degradation signal; based on the status of the autonomous parking system, the step of determining whether the target vehicle has a brake redundancy requirement includes: when it is detected that the status of the autonomous parking system is a failure state, the target vehicle has a brake redundancy requirement; wherein the failure state includes at least one of the following: a brake signal is missing or abnormal; a push rod travel signal is missing or abnormal; a deceleration signal is missing or abnormal; and a degradation signal is triggered.

[0006] Furthermore, based on the braking redundancy requirement, a preset braking redundancy strategy is executed to achieve the braking redundancy of the target vehicle, specifically including: obtaining the braking force parameters of the target vehicle; determining the target braking force of the target vehicle according to the braking force parameters; determining the wheel-side negative torque of the target vehicle and the target deceleration of the target vehicle according to the target braking force; and controlling the actual deceleration of the target vehicle based on the wheel-side negative torque and the target deceleration to achieve braking redundancy of the target vehicle.

[0007] Furthermore, based on the wheel-side negative torque and the target deceleration, the actual deceleration of the target vehicle is controlled to achieve braking redundancy of the target vehicle, specifically including: applying wheel-side negative torque to the target vehicle, and obtaining a vehicle speed signal of the target vehicle during the process of applying the wheel-side negative torque; obtaining an actual deceleration based on the vehicle speed signal; determining whether the actual deceleration reaches the target deceleration; if so, braking the target vehicle at the actual deceleration to achieve braking redundancy of the target vehicle; if not, controlling the actual deceleration based on the relationship between the actual deceleration and the wheel-side negative torque to achieve braking redundancy of the target vehicle.

[0008] Further, in the step of determining the target braking force of the target vehicle according to the braking force parameter, The expression of target braking force is: , In the formula, F For the target braking force, m is the fully loaded weight of the target vehicle, is the road adhesion coefficient, L 2 is the distance from the rear axle to the center of gravity of the target vehicle, h is the fully loaded center of gravity height of the target vehicle, L 1 is the wheelbase of the target vehicle.

[0009] Further, in the step of determining the wheel side negative torque of the target vehicle and the target deceleration of the target vehicle according to the target braking force, The expression of negative wheel torque is: ， In the formula, T is the negative torque at the wheel end, F For the target braking force, r is the wheel radius of the target vehicle.

[0010] Further, in the step of controlling the actual deceleration based on the relationship between the actual deceleration and the wheel side negative torque to achieve the braking redundancy of the target vehicle, The relationship between the actual deceleration and the negative torque at the wheel is expressed as: , In the formula,a is the actual deceleration, k is the empirical coefficient, T is the negative torque at the wheel end, m is the mass of the target vehicle, r is the wheel radius of the target vehicle.

[0011] Compared with the prior art, the above technical solution provided by the present application at least includes the following technical effects: The present application provides a vehicle braking redundancy method. The vehicle braking redundancy method provided by the present application can use a vehicle power controller in a valet parking system to achieve braking redundancy, overcoming the problems of high cost, heavy weight, and complex assembly caused by the use of RBU. By using a vehicle power controller to achieve braking redundancy, a series of disadvantages faced by the traditional use of RBU are effectively avoided. Compared with RBU, the vehicle power controller, as an important component in the vehicle system, does not require the additional purchase and loading of a special RBU, greatly reduces the hardware cost investment, and helps to reduce the overall weight of the vehicle. In addition, the installation of RBU often requires major changes to the vehicle's braking system, while the use of a vehicle power controller to achieve braking redundancy can make full use of the vehicle's existing architecture, without the need for large-scale modifications and complex assembly processes, which can simplify the assembly process and improve production efficiency.

[0012] In a second aspect, the present application provides a vehicle braking redundancy system, the system comprising: A signal acquisition module, configured to monitor a status signal of the target vehicle in response to a valet parking instruction of the target vehicle; wherein the status signal is used to indicate a status of an autonomous parking system of the target vehicle; A state acquisition module, used for acquiring the state of the autonomous parking system based on the state signal; A demand judgment module, used to judge whether a target vehicle has a demand for brake redundancy based on the state of the autonomous parking system; The brake redundancy module is used to execute a preset brake redundancy strategy based on the brake redundancy requirement when the target vehicle has a brake redundancy requirement to achieve brake redundancy of the target vehicle.

[0013] In a third aspect, the present application provides a vehicle comprising a processor, a memory, and a program or instruction stored in the memory and executable on the processor, wherein the program or instruction, when executed by the processor, implements the vehicle braking redundancy method as in the first aspect.

[0014] In a fourth aspect, the present application provides a readable storage medium, on which a program or instruction is stored, and when the program or instruction is executed by a processor, the steps of the vehicle braking redundancy method as in the first aspect are implemented.

[0015] It can be understood that the technical effects of the technical solutions provided in the second, third and fourth aspects can be found in the relevant description of the first aspect, and will not be repeated here.

[0016] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a flow chart of a vehicle braking redundancy method provided by an embodiment of the present application; Figure 2 is a structural block diagram of a vehicle brake redundancy system provided in an embodiment of the present application; Figure 3 It is a structural block diagram of a vehicle provided in an embodiment of the present application. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions 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 creative work are within the scope of protection of this application.

[0019] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here. In addition, the "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally represents that the objects associated with each other are in an "or" relationship.

[0020] The following is combined with Figure 1 , the vehicle braking redundancy method provided in the embodiment of the present application is described in detail through specific embodiments and their application scenarios.

[0021] It should be noted that the vehicle braking redundancy method provided in the embodiment of the present application can be applied to hybrid electric vehicles, and the vehicle power controller (Hybrid Total Control Unit, hereinafter referred to as HTCU) of the hybrid electric vehicle can be used to achieve braking redundancy. The HTCU can coordinate and manage multiple power system components of the vehicle, including the engine, motor, battery, etc., to ensure that the vehicle can operate efficiently and stably under different working conditions.

[0022] See also Figure 1, shown is a vehicle braking redundancy method provided in the first aspect of an embodiment of the present application, the method may include but is not limited to steps S101 to S104.

[0023] S101: In response to a valet parking instruction of a target vehicle, monitoring a status signal of the target vehicle; wherein the status signal is used to indicate a status of an autonomous parking system of the target vehicle.

[0024] It is understandable that during the valet parking process, the automated valet parking system (AVP) will send braking instructions to the autonomous parking system based on factors such as the vehicle's driving status and the distance to the target parking space to ensure that the vehicle can travel along the predetermined path and speed and park accurately at the appropriate location. Among them, the autonomous parking system can adopt the OneBox intelligent integrated braking system, the electronic power braking system or the electronic parking brake system.

[0025] In this embodiment, the valet parking command is received by the central control system of the target vehicle. The command can be issued by the user on the mobile phone APP or sent through the smart terminal device in the parking lot. After the central control system receives the command, it transmits the command to the HTCU through the CAN bus. Through the signal receiving unit of the HTCU itself, the status signal sent from the vehicle sensor group can be received. The vehicle sensor group includes but is not limited to the brake pedal position sensor, the push rod stroke sensor, the acceleration sensor, etc. The above sensors can be used to judge the braking intention, braking intensity, braking effect and the state of the braking system. Therefore, the status signal of the target vehicle is monitored, which can be used to comprehensively indicate the state of the autonomous parking system of the target vehicle. When the HTCU receives the status signal sent from the vehicle sensor group, a differential signal input method can be used to enhance the anti-interference ability of the status signal reception, and ensure that the status signal can be accurately and stably monitored by the HTCU. By monitoring the status signal of the target vehicle, the state of the autonomous parking system of the target vehicle can be more comprehensively and accurately understood, so as to avoid the failure of the autonomous parking system of the target vehicle during the AVP valet parking process, which affects the safety of the target vehicle.

[0026] S102: Acquire the state of the autonomous parking system based on the state signal.

[0027] In this embodiment, the autonomous parking system may include an autonomous parking main controller and an autonomous parking actuator. The HTCU may obtain the status of the autonomous parking main controller and the autonomous parking actuator of the target vehicle through the CAN bus. The signal processing unit of the HTCU itself can parse and process the status signal of the monitored target vehicle, and compare the parsed signal with the preset autonomous parking system status threshold or mode to determine the specific working state of the current autonomous parking system of the target vehicle. The working state can be divided into a normal state and a failure state. By real-time monitoring and analyzing the status signal of the target vehicle, potential problems and faults of the autonomous parking system can be discovered in time, so that subsequent measures can be taken to avoid the occurrence of dangerous situations. The HTCU can adjust the strategy in time according to the actual situation to ensure the safety of the target vehicle during the AVP valet parking process.

[0028] S103: Based on the state of the autonomous parking system, determine whether the target vehicle has a braking redundancy requirement.

[0029] In this embodiment, based on the state of the autonomous parking system, it is determined whether the target vehicle has a need for brake redundancy. If the autonomous parking system is currently in a normal state, it is determined that the target vehicle does not have a need for brake redundancy; if the autonomous parking system is currently in a failed state, it is determined that the target vehicle has a need for brake redundancy. The HTCU mainly determines the potential impact of the current state of the autonomous parking system on the braking performance based on the preset rules. It is believed that the current state of the autonomous parking system may further deteriorate during the subsequent AVP valet parking process, resulting in a decrease in the braking performance of the target vehicle, thereby affecting the safety of the AVP valet parking process. The HTCU will determine that the current state of the autonomous parking system is a failed state, and the target vehicle has a need for brake redundancy. Among them, the preset rules can be set based on a comprehensive consideration of multiple factors such as the performance of each component in the autonomous parking system, the autonomous parking safety standard, and the operating conditions of the target vehicle, and can be flexibly adjusted according to actual conditions. When the current state of the autonomous parking system is a failed state, brake redundancy can be enabled, which can effectively avoid collision accidents caused by subsequent brake failures and ensure the safety of the target vehicle and surrounding personnel and facilities.

[0030] S104: If yes, based on the braking redundancy requirement, execute a preset braking redundancy strategy to achieve braking redundancy of the target vehicle.

[0031] In this embodiment, the preset brake redundancy strategy is executed by the HTCU. During the vehicle design and manufacturing stage, multiple brake redundancy strategies can be pre-stored in the HTCU according to the vehicle power system performance and the design requirements of the autonomous parking system. The brake redundancy strategy can be designed according to the brake redundancy requirements and operating conditions of different vehicles. During the process of the HTCU executing the preset brake redundancy strategy, the HTCU will continue to monitor the state signal of the target vehicle to dynamically adjust the corresponding braking operation to achieve the brake redundancy of the target vehicle.

[0032] In some embodiments, the status signal includes a brake signal, a push rod travel signal, a deceleration signal and a degradation signal; based on the status of the autonomous parking system, the step of determining whether the target vehicle has a brake redundancy requirement includes: when it is detected that the status of the autonomous parking system is a failure state, the target vehicle has a brake redundancy requirement; wherein the failure state includes at least one of the following: the brake signal is missing or abnormal; the push rod travel signal is missing or abnormal; the deceleration signal is missing or abnormal; the degradation signal is triggered.

[0033] In this embodiment, it is detected whether the state of the autonomous parking system is in a failure state. The failure state is determined by the signal monitored during the braking process of the target vehicle or the signal used for early warning before braking. The HTCU can use a pre-set algorithm to process the monitored state signal. The HTCU can use these algorithms to filter and normalize the state signal, convert the analog signal into a digital signal, and compare it with the standard signal range and historical data stored in the storage unit. For the brake signal and the push rod stroke signal, an analysis algorithm based on a time series can be used to determine the continuity and change trend of the brake signal and the push rod stroke signal; for the deceleration signal, a dynamic algorithm and an error analysis algorithm can be used to compare it with the theoretical value calculated according to the physical characteristics of the autonomous parking system during the braking process; for the degradation signal, a simple logic judgment algorithm can be used. When the degradation signal is triggered, it indicates that the state of the autonomous parking system is detected to be in a failure state.

[0034] It is understandable that when detecting whether the state of the above-mentioned state signal is in a failure state, a time window and an allowable error range can be set so that the HTCU will consider the fault tolerance range when determining that the state of the autonomous parking system is in a failure state. In the embodiment of the present application, the HTCU does not simply determine that the state of the autonomous parking system is in a failure state based on a single fluctuation of a single signal, but can make a comprehensive judgment based on multiple signals, thereby reducing the possibility of misjudgment due to a single signal and improving the accuracy of the HTCU in detecting the state of the autonomous parking system.

[0035] In this embodiment, the HTCU can continuously monitor the brake signal through the brake pedal position sensor of the target vehicle. When the vehicle can brake normally, the brake pedal position sensor will send a continuous and expected range of electrical signals corresponding to the brake pedal position to the HTCU. When the brake signal monitored by the HTCU remains constant for a period of time or the signal value exceeds the normal range (such as the signal suddenly changes to a high level or is at an intermediate level without change), it is considered that the brake signal is missing or abnormal.

[0036] In this embodiment, the HTCU can continuously monitor the push rod stroke signal through the push rod stroke sensor on the push rod of the brake master cylinder of the target vehicle. When the vehicle can brake normally, the push rod stroke signal will produce corresponding linear changes with the braking operation. When performing the corresponding braking operation, when the push rod stroke signal monitored by the HTCU is always zero for a period of time or there is a discontinuous jump, it is considered that the push rod stroke signal is missing or abnormal.

[0037] In this embodiment, the HTCU can continuously monitor the deceleration signal through the acceleration sensor of the target vehicle. When the vehicle can brake normally, according to Newton's second law, combined with the relevant performance parameters during the braking process, the HTCU can predict the deceleration range of the target vehicle. When the deceleration signal monitored by the HTCU deviates greatly from the expected deceleration range of the target vehicle, or the deceleration signal remains at zero for a long time and the vehicle does not start braking, it is considered that the deceleration signal is missing or abnormal.

[0038] In this embodiment, the HTCU can monitor whether a degradation signal is triggered through a system fault diagnosis module in the autonomous parking system. The degradation signal is usually triggered when a fault occurs in the braking system or a related system and may affect the normal operation and braking performance of the target vehicle. Exemplary situations that trigger a degradation signal include but are not limited to: errors, loopholes or anomalies in the software program of the autonomous parking system, which cause the system to fail to operate normally or make wrong decisions; communication interruptions, data transmission errors or excessive delays between modules within the autonomous parking system (such as between sensors and controllers, controllers and actuators) and between other systems; one or more of the sensors of the autonomous parking system fail, such as signal loss, data anomalies or damage to the sensor itself. When one or more of the above situations occur, a degradation signal is triggered.

[0039] In some embodiments, based on the braking redundancy requirement, a preset braking redundancy strategy is executed to achieve the braking redundancy of the target vehicle, specifically including: obtaining the braking force parameters of the target vehicle; determining the target braking force of the target vehicle based on the braking force parameters; determining the wheel-side negative torque of the target vehicle and the target deceleration of the target vehicle based on the target braking force; based on the wheel-side negative torque and the target deceleration, controlling the actual deceleration of the target vehicle to achieve braking redundancy of the target vehicle.

[0040] In this embodiment, in the AVP valet parking process, in order to allow the target vehicle to park safely and accurately in the predetermined position, the braking process of the vehicle needs to be precisely controlled. The target braking force can be determined according to the braking force parameter, and the braking force parameter includes the inherent characteristics and current state information of the target vehicle. The inherent characteristics and current state information of the target vehicle can be used to calculate the braking force required to achieve the expected braking effect. In an electric vehicle or hybrid electric vehicle, when the wheel side negative torque is determined according to the target braking force, the braking demand can be converted into a control requirement for the motor, and the motor controller can adjust the armature current and magnetic flux of the motor according to the calculated wheel side negative torque, so that the motor generates a corresponding electromagnetic torque, thereby realizing electric braking. By accurately calculating the target braking force, wheel side negative torque and target deceleration, the braking process of the target vehicle can be made more accurate and stable, avoiding the situation of insufficient braking or excessive braking, and optimizing the performance of the braking system from different angles, thereby improving the braking performance of the target vehicle during autonomous parking.

[0041] In some embodiments, based on the wheel-side negative torque and the target deceleration, the actual deceleration of the target vehicle is controlled to achieve braking redundancy of the target vehicle, specifically including: applying wheel-side negative torque to the target vehicle, and obtaining a vehicle speed signal of the target vehicle during the process of applying the wheel-side negative torque; obtaining an actual deceleration based on the vehicle speed signal; determining whether the actual deceleration reaches the target deceleration; if so, braking the target vehicle at the actual deceleration to achieve braking redundancy of the target vehicle; if not, controlling the actual deceleration based on the relationship between the actual deceleration and the wheel-side negative torque to achieve braking redundancy of the target vehicle.

[0042] In this embodiment, the actual deceleration is obtained according to the vehicle speed signal, and the HTCU will perform a time series analysis on the vehicle speed signal. Within a period of time, the vehicle speed values ​​at multiple moments are recorded to calculate the actual deceleration. The HTCU compares the obtained actual deceleration with the target deceleration. When the actual deceleration reaches or approaches the target deceleration, that is, within the preset error range, it is considered that the current braking state meets the requirements, and the target vehicle is braked at the actual deceleration to achieve the braking redundancy of the target vehicle. At the same time, the HTCU will continue to monitor the actual deceleration of the target vehicle to ensure that the target vehicle decelerates stably until it stops. When the actual deceleration does not reach the target deceleration, the HTCU will control the actual deceleration based on the relationship between the actual deceleration and the wheel side negative torque. The actual deceleration is less than the target deceleration, which may be due to insufficient wheel side negative torque. At this time, the wheel side negative torque can be increased. For example, according to the characteristic curve of the motor, the armature current or magnetic flux can be increased to increase the electromagnetic torque of the motor, and the hydraulic pressure of the brake master cylinder can be increased to generate additional braking force. On the contrary, when the actual deceleration is greater than the target deceleration, the target vehicle may brake too hard, affecting comfort and safety. The negative torque on the wheel side or the hydraulic pressure of the brake master cylinder can be appropriately reduced. The HTCU continuously monitors and adjusts the actual deceleration to ensure that the target vehicle brakes at a rate close to the target deceleration, so that the target vehicle can brake safely.

[0043] In some embodiments, in the step of determining the target braking force of the target vehicle according to the braking force parameter, the expression of the target braking force is: , In the formula, F For the target braking force, m is the fully loaded weight of the target vehicle, is the road adhesion coefficient, L 2 is the distance from the rear axle to the center of gravity of the target vehicle, h is the fully loaded center of gravity height of the target vehicle, L 1 is the wheelbase of the target vehicle.

[0044] In this embodiment, the fully loaded weight of the target vehicle can be directly read by the HTCU or obtained by real-time monitoring based on the weight sensor of the target vehicle. The road adhesion coefficient can be obtained using a wheel slip rate sensor in combination with a vehicle dynamics model. According to the relationship curve between different slip rate ranges and the adhesion coefficient, the current road adhesion coefficient can be roughly estimated. For example, the road adhesion coefficient can take a fixed empirical value of 0.8. The distance from the center of gravity of the rear axle to the target vehicle and the wheelbase are fixed design parameters, which can be directly read from the storage unit by the HTCU. The fully loaded center of gravity height of the target vehicle can be estimated by the design data of the target vehicle and the vehicle load distribution model, or the HTCU can obtain it through a center of gravity position sensor that the target vehicle can be equipped with.

[0045] In this embodiment, the expression of the target braking force of the embodiment of the present application takes into account the braking force parameters such as the full load weight of the target vehicle, the distance from the rear axle to the center of gravity, and the road adhesion coefficient, so that the determined target braking force is more accurate. Under different vehicle full load conditions and road conditions, the braking force requirements are different. For example, the inertia of the target vehicle is large under the fully loaded state, and a larger braking force is required. The braking force cannot be too large under the road surface with a low adhesion coefficient. Through the expression of the target braking force of the embodiment of the present application, the appropriate target braking force can be determined according to the actual situation to improve the safety during the braking process. At the same time, the distance from the rear axle to the center of gravity and the height of the center of gravity when fully loaded are taken into account, which helps to prevent the target vehicle from being unstable during the braking process, such as tail swinging or excessive forward tilting. When the center of gravity is high or the distance from the rear axle to the center of gravity is large, the braking force can be reasonably adjusted according to this expression to avoid the target vehicle from losing stability due to unreasonable braking force distribution. The road adhesion coefficient can also be adjusted so that the target vehicle can achieve the best braking effect on different road surfaces.

[0046] In some embodiments, in the step of determining the wheel side negative torque of the target vehicle and the target deceleration of the target vehicle according to the target braking force, The expression of negative wheel torque is: ， In the formula, T is the negative torque at the wheel end, F For the target braking force, r is the wheel radius of the target vehicle.

[0047] In this embodiment, the wheel side negative torque is determined by the expression of the wheel side negative torque, the electric or hybrid vehicle can better control the electric brake system, and the motor controller can adjust the working state of the motor according to the wheel side negative torque, so that the motor enters the power generation mode and generates the corresponding electromagnetic torque, thereby achieving the braking redundancy of the target vehicle. The influence of the transmission ratio can also be considered in the process of determining the wheel side negative torque. The target deceleration of the target vehicle can be determined according to Newton's second law. Determining the wheel side negative torque and the target deceleration according to the target braking force helps to achieve the braking redundancy of the target vehicle.

[0048] In some embodiments, in the step of controlling the actual deceleration based on the relationship between the actual deceleration and the wheel side negative torque to achieve the braking redundancy of the target vehicle, The relationship between the actual deceleration and the negative torque at the wheel is expressed as: , In the formula, a is the actual deceleration, k is the empirical coefficient, Tis the negative torque at the wheel end, m is the mass of the target vehicle, r is the wheel radius of the target vehicle.

[0049] In this embodiment, in actual application, the negative torque of the wheel side is transmitted to the wheel side with loss. In order to make the relationship expression between the actual deceleration and the negative torque of the wheel side more consistent with the actual situation, an empirical coefficient can be introduced. For example, the empirical coefficient can be 1.2. The empirical coefficient can be obtained through a large number of experiments and actual test data. By determining and monitoring the actual deceleration and dynamically adjusting it according to the relationship expression between the actual deceleration and the negative torque of the wheel side, it can be ensured that the braking redundancy of the target vehicle is achieved in the event of failure of the autonomous parking system.

[0050] See also Figure 2 , shown is a structural block diagram of a vehicle braking redundancy system provided in an embodiment of the second aspect of the present application.

[0051] It should be noted that, in some embodiments, the HTCU may be integrated with an electronic caliper EPB. In the event that the autonomous parking system fails, the HTCU may also brake the vehicle by controlling the electronic caliper EPB to achieve braking redundancy of the target vehicle. In the event that the autonomous parking system fails, the HTCU may also request the P gear and use the transmission P gear lock to brake the vehicle to achieve braking redundancy of the target vehicle.

[0052] It should be noted that the vehicle brake redundancy method provided in the embodiment of the present application can be executed by a vehicle brake redundancy system, or a module in the system for executing the method for loading vehicle brake redundancy. In the embodiment of the present application, the vehicle brake redundancy control method provided in the embodiment of the present application is described by taking the vehicle brake redundancy system executing the method for loading vehicle brake redundancy as an example.

[0053] In some embodiments of the present application, the vehicle brake redundancy system provided by the embodiments of the present application includes: A signal acquisition module 201 is used to monitor a state signal of the target vehicle in response to a valet parking instruction of the target vehicle; wherein the state signal is used to indicate a state of an autonomous parking system of the target vehicle; A state acquisition module 202, used to acquire the state of the autonomous parking system based on the state signal; A demand determination module 203 is used to determine whether the target vehicle has a brake redundancy demand based on the state of the autonomous parking system; The brake redundancy module 204 is used to execute a preset brake redundancy strategy based on the brake redundancy requirement to achieve brake redundancy of the target vehicle when the target vehicle has a brake redundancy requirement.

[0054] The vehicle brake redundancy system in the embodiment of the present application may be a device, or a component, integrated circuit, or chip in a terminal. The device may be a mobile electronic device or a non-mobile electronic device. Exemplarily, the mobile electronic device may be a mobile phone, a tablet computer, a laptop computer, a PDA, an in-vehicle electronic device, a wearable device, an ultra-mobile personal computer (UMPC), a netbook, or a personal digital assistant (PDA), etc., and the non-mobile electronic device may be a server, a network attached storage (NAS), or a personal computer (PC), etc., which is not specifically limited in the embodiment of the present application.

[0055] The vehicle brake redundancy system provided in the embodiment of the present application can achieve Figure 1 To avoid repetition, the various processes of implementing the vehicle braking redundancy system in the embodiment will not be described here.

[0056] Alternatively, if Figure 3 As shown, an embodiment of the present application also provides a vehicle, including a processor 301, a memory 302, and a program or instruction 303 stored in the memory and executable on the processor. When the program or instruction is executed by the processor, each process of the above-mentioned vehicle braking redundancy method embodiment is implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

[0057] An embodiment of the present application also provides a readable storage medium, on which a program or instruction is stored. When the program or instruction is executed by a processor, each process of the above-mentioned vehicle braking redundancy method embodiment is implemented, and the same technical effect can be achieved. To avoid repetition, it will not be repeated here.

[0058] The processor is the processor in the target vehicle in the above embodiment. The readable storage medium includes a computer readable storage medium, such as a computer read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0059] It should be noted that, in this article, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise one..." do not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0060] 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, 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, a magnetic disk, or an optical disk), and includes a number of instructions for a terminal (which can be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) to execute the methods described in each embodiment of the present application.

[0061] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present application, ordinary technicians in this field can also make many forms without departing from the purpose of the present application and the scope of protection of the claims, all of which are within the protection of the present application.

Claims

1. A vehicle braking redundancy method, characterized in that: The method comprises: In response to a valet parking instruction of a target vehicle, monitoring a status signal of the target vehicle; wherein the status signal is used to indicate a status of an autonomous parking system of the target vehicle; Based on the status signal, obtaining a status of the autonomous parking system; Based on the state of the autonomous parking system, determining whether the target vehicle has a braking redundancy requirement; If so, based on the braking redundancy requirement, a preset braking redundancy strategy is executed to achieve braking redundancy of the target vehicle.

2. The vehicle braking redundancy method according to claim 1, characterized in that: The state signal includes a brake signal, a push rod travel signal, a deceleration signal and a degradation signal; The step of determining whether the target vehicle has a braking redundancy requirement based on the state of the autonomous parking system includes: When it is detected that the state of the autonomous parking system is a failure state, the target vehicle has a braking redundancy requirement; Wherein, the failure state includes at least one of the following: the brake signal is missing or abnormal; the push rod stroke signal is missing or abnormal; the deceleration signal is missing or abnormal; the degradation signal is triggered.

3. The vehicle braking redundancy method according to claim 1, characterized in that: The step of executing a preset braking redundancy strategy based on the braking redundancy requirement to achieve braking redundancy of the target vehicle specifically includes: Obtaining a braking force parameter of the target vehicle; Determining a target braking force of the target vehicle according to the braking force parameter; Determining the wheel side negative torque of the target vehicle and the target deceleration of the target vehicle according to the target braking force; Based on the wheel side negative torque and the target deceleration, the actual deceleration of the target vehicle is controlled to achieve braking redundancy of the target vehicle.

4. The vehicle braking redundancy method according to claim 3, characterized in that: The step of controlling the actual deceleration of the target vehicle based on the wheel side negative torque and the target deceleration to achieve braking redundancy of the target vehicle specifically includes: Applying the wheel side negative torque to the target vehicle, and obtaining a vehicle speed signal of the target vehicle during the process of applying the wheel side negative torque; obtaining the actual deceleration according to the vehicle speed signal; determining whether the actual deceleration reaches the target deceleration; If so, braking the target vehicle at the actual deceleration to achieve braking redundancy of the target vehicle; If not, based on the relationship between the actual deceleration and the wheel side negative torque, the actual deceleration is controlled to achieve braking redundancy of the target vehicle.

5. The vehicle braking redundancy method according to claim 3, characterized in that: In the step of calculating the target braking force of the target vehicle according to the braking force parameter, The expression of the target braking force is: ， In the formula, F For the target braking force, m is the fully loaded weight of the target vehicle, is the road adhesion coefficient, L 2 is the distance from the rear axle to the center of gravity of the target vehicle, h is the fully loaded center of gravity height of the target vehicle, L 1 is the wheelbase of the target vehicle.

6. The vehicle braking redundancy method according to claim 3, characterized in that: In the step of calculating the wheel side negative torque of the target vehicle and the target deceleration of the target vehicle according to the target braking force, The expression of the wheel side negative torque is: ， In the formula, T is the negative torque at the wheel end, F For the target braking force, r is the wheel radius of the target vehicle.

7. The vehicle braking redundancy method according to claim 4, characterized in that: In the step of controlling the actual deceleration based on the relationship between the actual deceleration and the wheel side negative torque to achieve braking redundancy of the target vehicle, The relationship between the actual deceleration and the wheel side negative torque is expressed as: ， In the formula, a is the actual deceleration, k is the empirical coefficient, T is the negative torque at the wheel end, m is the mass of the target vehicle, r is the wheel radius of the target vehicle.

8. A vehicle braking redundancy system, characterized in that: The system comprises: A signal acquisition module, configured to monitor a status signal of the target vehicle in response to a valet parking instruction of the target vehicle; wherein the status signal is used to indicate a status of an autonomous parking system of the target vehicle; a state acquisition module, configured to acquire a state of the autonomous parking system based on the state signal; a demand determination module, configured to determine whether the target vehicle has a brake redundancy demand based on the state of the autonomous parking system; The braking redundancy module is used to execute a preset braking redundancy strategy based on the braking redundancy requirement when the target vehicle has the braking redundancy requirement, so as to achieve braking redundancy of the target vehicle.

9. A vehicle, characterized in that: The invention comprises a processor, a memory and a program or instruction stored in the memory and executable on the processor, wherein the program or instruction, when executed by the processor, implements the vehicle braking redundancy method as claimed in any one of claims 1 to 7.

10. A readable storage medium, characterized in that: The readable storage medium stores programs or instructions, and when the programs or instructions are executed by the processor, the steps of the vehicle braking redundancy method as described in any one of claims 1 to 7 are implemented.

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