Backup parking methods, equipment, media and vehicles

Abstract

This application provides a backup parking method, device, medium, and vehicle. The backup parking method includes: based on fault information and parking status information of the electronic parking brake system, controlling the hydraulic system to provide parking brake pressure to the hydraulic brakes of the target wheels and locking the corresponding hydraulic valves to achieve parking. This method can utilize existing vehicle service braking systems to achieve hydraulic backup parking when the electronic parking brake system fails, is easy to implement, and meets vehicle parking safety requirements.

Description

Technical Field

[0001] This application relates to the automotive field, and more specifically to a backup parking method, device, medium, and vehicle. Background Technology

[0002] In related technologies, brake backup control systems typically integrate the Electronic Park Brake (EPB) system software into two Electronic Control Units (ECUs). When the main ECU fails, the other ECU controls the motor to achieve single-sided or double-sided parking, meeting parking backup requirements. This approach requires consideration of multi-ECU interaction and controller integration, resulting in high implementation costs and technical complexity per vehicle. Furthermore, if the EPB motor hardware fails, the lack of backup for this actuator could still lead to parking failure. Summary of the Invention

[0003] This application is made in consideration of the above-mentioned problems. This application provides a backup parking method, device, medium, and vehicle that can realize hydraulic backup parking when the electronic parking brake system fails, utilizing the existing vehicle service braking system. It is easy to implement and meets the requirements of vehicle parking safety.

[0004] According to one aspect of this application, the backup parking method includes:

[0005] Based on the fault information and parking status information of the electronic parking brake system, the control hydraulic system provides parking brake pressure to the hydraulic brakes of the target wheels and locks the corresponding hydraulic valves to achieve parking.

[0006] In one embodiment of this application, controlling the hydraulic system to provide parking brake pressure to the hydraulic brake of the target wheel includes:

[0007] When a brake pedal signal is detected, the hydraulic system is controlled to provide parking brake pressure to the hydraulic brakes of the target wheel based on the brake pedal signal.

[0008] In one embodiment of this application, controlling the hydraulic system to provide parking brake pressure to the hydraulic brake of the target wheel based on the brake pedal signal includes:

[0009] When the braking force corresponding to the current brake pedal signal meets the parking requirements, the hydraulic system is controlled to provide parking braking pressure to the hydraulic brakes of the target wheel according to the current braking force.

[0010] When the braking force corresponding to the current brake pedal signal is insufficient to meet the parking requirements, a prompt signal is sent to remind the user to increase the depth of the brake pedal so that the braking force corresponding to the brake pedal signal meets the parking requirements.

[0011] In one embodiment of this application, controlling the hydraulic system to provide parking brake pressure to the hydraulic brake of the target wheel based on the brake pedal signal further includes:

[0012] Determine whether the braking force corresponding to the current brake pedal signal meets the parking requirements;

[0013] When the braking force corresponding to the current brake pedal signal is greater than or equal to the parking braking force, it is determined that the braking force corresponding to the current brake pedal signal meets the parking requirements. The parking braking force is determined based on the motor speed, wheel speed, and slope value.

[0014] When the braking force corresponding to the current brake pedal signal is less than the parking braking force, it is determined that the braking force corresponding to the current brake pedal signal does not meet the parking requirements.

[0015] In one embodiment of this application, the method for obtaining the parking status information includes:

[0016] Parking status information is obtained from the electronic parking brake system and / or the parking button.

[0017] In one embodiment of this application, when the target wheel is driven by a distributed motor, the backup parking method further includes:

[0018] Based on the rear axle motor resolver angle signal, rear axle wheel speed direction and pulse value, the hydraulic leakage during hydraulic parking is determined;

[0019] When the leakage amount exceeds a preset leakage threshold, the hydraulic system is pressurized.

[0020] In one embodiment of this application, the backup parking method further includes:

[0021] Obtain the voltage information of the low-voltage battery;

[0022] When the voltage information is lower than a preset voltage threshold, the power battery is activated to charge the low-voltage battery.

[0023] In one embodiment of this application, before controlling the hydraulic system to provide parking brake pressure to the hydraulic brake of the target wheel based on fault information and parking status information of the electronic parking brake system, the backup parking method further includes:

[0024] Fault detection was performed on the electronic parking brake system.

[0025] When a preset fault is detected, corresponding fault information is generated.

[0026] In one embodiment of this application, the preset fault includes one or more of the following: power supply fault, motor fault, return loop harness fault, and left and right execution circuit fault.

[0027] According to a second aspect of this application, a control device is provided, the control device including a memory and a processor, the memory storing a computer program executed by the processor, the computer program, when executed by the processor, causing the control device on which the processor is installed to perform the backup parking method as described in any of the first aspects above.

[0028] According to a third aspect of this application, a storage medium is provided, on which a computer program is stored, the computer program running on a computer, and the computer program, when running, causes the computer to perform the backup parking method as described in any of the first aspects above.

[0029] According to a fourth aspect of this application, a vehicle is provided, the vehicle comprising:

[0030] The control device as described in any of the second aspects above, or,

[0031] Storage media as described in any of the third aspects above.

[0032] This application utilizes the existing vehicle service braking system to achieve hydraulic backup parking in the event of EPB failure, which is easy to implement and meets vehicle parking safety requirements. Attached Figure Description

[0033] The above and other objects, features, and advantages of the present invention will become more apparent from the more detailed description of the embodiments of the invention in conjunction with the accompanying drawings. The drawings are provided to further illustrate the embodiments of the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings, the same reference numerals generally represent the same parts or steps.

[0034] Figure 1 This is a schematic block diagram of a vehicle braking system architecture according to an embodiment of this application;

[0035] Figure 2 This is a schematic diagram of the hydraulic control of a vehicle braking system during driving, according to an embodiment of this application;

[0036] Figure 3 This is a schematic flowchart of a backup parking method according to an embodiment of this application;

[0037] Figure 4 This is a schematic diagram illustrating the principle of locking the corresponding hydraulic valve during parking brake operation according to an embodiment of this application;

[0038] Figure 5 This is a schematic flowchart illustrating the generation of hydraulic system control signals according to an embodiment of this application;

[0039] Figure 6 This is a schematic flowchart of a backup parking method according to another embodiment of this application. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the present invention more apparent, exemplary embodiments according to the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are merely a part of the embodiments of the present invention, and not all of the embodiments of the present invention. It should be understood that the present invention is not limited to the exemplary embodiments described herein. Based on the embodiments of the present invention described herein, all other embodiments obtained by those skilled in the art without inventive effort should fall within the protection scope of the present invention.

[0041] Because the technical complexity of the redundant parking scheme through dual backup of controller and some actuators is high, and because the backup parking may still fail when the EPB motor hardware fails, there is no backup for this hardware actuator. Therefore, this application proposes a backup parking method, device, medium and vehicle based on the existing service braking system.

[0042] Vehicle braking systems typically include service braking systems and parking braking systems. The parking braking system mainly comprises: a control mechanism, an electronic control unit, an actuator, and warning indicator lights. The control mechanism can be an EPB switch, and the actuator mainly includes an EPB caliper motor, a reduction mechanism, a helical rotation mechanism, a brake wheel cylinder piston, friction pads, and a brake disc. Helical rotation mechanisms are mainly divided into two types: threaded drive mechanisms and ball screw drive mechanisms. The service braking system provides braking force to the wheels through a controlled hydraulic system, reducing the speed of the vehicle or even stopping it. In this application, the hydraulic system includes a hydraulic pump, hydraulic valves, hydraulic cylinders, hydraulic lines, and an oil tank. The hydraulic pump is the power source of the hydraulic system, mechanically pumping hydraulic oil into the hydraulic lines and hydraulic cylinders. The hydraulic valves control the flow direction and speed of the hydraulic fluid, thereby enabling the control and adjustment of various parts of the vehicle. The hydraulic cylinders are the actuators of the hydraulic system, converting hydraulic pressure into mechanical force to complete the vehicle's movement and adjustment tasks. The hydraulic lines connect the various components, transmitting hydraulic fluid to the locations requiring control. The hydraulic oil tank stores the hydraulic oil.

[0043] First, refer to Figure 1 This application describes a vehicle braking system according to an embodiment of the present application.

[0044] In the diagram, the thick black line represents the hydraulic circuit of the vehicle's braking system, the gray line represents the power realization circuit, and the dashed line represents the wiring harness circuit. Figure 1 As shown, the EPB controller connects to an onboard tablet computer (PDA) or an EPB switch. The PAD is a virtual switch used to acquire the driver's intention to clamp and release the EPB, and sends the acquired signals to the vehicle bus as required. The EPB controller receives relevant signals through the vehicle bus. The EPB switch is a physical switch used to acquire the driver's intention to clamp and release the EPB, and is connected to the EPB controller via a hardwired connection. The service brake system controller is connected to the EPB controller through the vehicle bus. The vehicle bus includes, but is not limited to, the Controller Area Network (CAN) bus, the Local Interconnect Network (LIN) bus, etc.

[0045] The vehicle controller, acting as the powertrain controller, controls power output by regulating motor speed and torque. The motors include a front left motor, a rear left motor, a front right motor, and a rear right motor. Each motor outputs power to the front left, rear left, front right, and rear right wheels via a drive shaft. The EPB controller controls the left and right rear axle motors to achieve caliper clamping and releasing for parking brake control. The service brake system controller controls braking by regulating the pressure in the brake's hydraulic circuit. The brakes convert the brake fluid pressure established by the vehicle stability controller into braking force on the wheels. The brakes include a front left brake, a rear left brake, a front right brake, and a rear right brake.

[0046] The EPB's working process typically includes: when the vehicle is stationary or the vehicle speed is below a certain threshold, the driver presses the parking button or operates the PDA. The EPB control unit receives the input current signal, and after integrating relevant signals from other controllers or sensors, it calculates the clamping force required by the vehicle and outputs the target current signal to the EPB caliper motor. The caliper motor starts to rotate and outputs torque. Through the reduction mechanism, the motor is decelerated and the torque is increased, forming the EPB caliper input torque. Then, through threaded drive or ball screw drive, the EPB caliper input torque is converted into piston clamping force to achieve parking, and the parking system status signal is sent to the instrument panel to inform the driver.

[0047] The following is for reference Figure 2This diagram illustrates the hydraulic control of a vehicle braking system according to an embodiment of the present application. The dashed lines with arrows indicate the direction of brake fluid flow when the brake pedal is depressed, the gray lines with arrows indicate the return direction when ABS is activated, and the black arrows indicate the direction of hydraulic fluid flow from the simulator. In addition to IV and OV, the valves in the diagram include a master cylinder separation valve (CSV) for isolating the master cylinder and wheel cylinder hydraulic pressure, and a plunger separation valve (PSV) for switching the brake hydraulic pressure source. When the PSV is closed, the brake pressure source is from the driver; when it is open, the brake pressure source is from the motor and pump. The brake fluid reservoir, master cylinder, and master cylinder simulator constitute a single circuit. The hydraulic brakes of the left front wheel (FL), right front wheel (FR), left rear wheel (RL), and right rear wheel (RR) are connected to hydraulic lines.

[0048] When the vehicle is powered on normally and the EPB is fault-free, the hydraulic pressure flow of the entire braking system is as follows when the driver presses the brake pedal. At this time, the master cylinder isolation valve isolates the pressure between the master cylinder and the wheel cylinders. The master cylinder isolation valve CSV is a normally closed valve, which is closed after power-on. The plunger pump isolation valve PSV is a normally open valve, which is normally open after power-on. The wheel cylinder pressure is achieved through the motor and pump. When the brake pedal is released, the hydraulic pressure of the four wheel cylinders returns to the brake fluid reservoir along the original path.

[0049] When the vehicle is powered on normally, the ignition is off, and the EPB is functioning correctly (with neither wheel able to park), the master cylinder isolation valve opens, connecting the master cylinder and wheel cylinder pressures. The PSV valve isolates the plunger pump from the circuit, while OV, PSV1, and PSV2 close, hydraulically shutting off the master cylinder from the master cylinder simulator, thus achieving mechanical backup braking. When the brake pedal is released, the hydraulic pressure from all four wheel cylinders returns to the brake fluid reservoir along the original path. In this situation, parking is still achieved by the EPB even after power is cut off.

[0050] Next, a backup parking method according to an embodiment of this application will be described in detail.

[0051] The backup parking method in this embodiment can be used for Figure 1In the vehicle braking system, specifically, it can be applied to the controller of the service braking system. The controller can be a microcontroller unit (MCU), a central processing unit (CPU), a digital signal processor (DSP), a single-chip microcomputer, an embedded device, or other forms of processing unit with data processing capabilities and / or instruction execution capabilities, and can control other components in the service braking system to perform the desired functions.

[0052] The method includes: based on the fault information and parking status information of the electronic parking brake system, controlling the hydraulic system to provide parking brake pressure to the hydraulic brakes of the target wheels and locking the corresponding hydraulic valves to achieve parking.

[0053] Here, the parking status information can include the status information of the EPB button, such as the status information of the parking button being pressed, or the operation command information of the user's in-vehicle tablet, such as the parking command.

[0054] For example, the EPB controller can collect the driver's switching requests and monitor the open circuit, short circuit, and other states of the left and right execution circuits, and finally send the system parking status information, fault information, etc. to the vehicle's common CAN bus. Thus, the service braking system can obtain fault information and parking status information in real time.

[0055] In this application, the target wheels can be two wheels on the front axle, two wheels on the rear axle, or four wheels, as long as they can meet the parking brake requirements.

[0056] A hydraulic valve that provides parking brake pressure and locks the hydraulic brakes of the target wheels can be a hydraulic valve for controlling the inflow and outflow of brake fluid into and out of the target wheel brakes. Specifically, the hydraulic valve includes a directional control valve through which the brake fluid flows into and out of each wheel brake.

[0057] For example, a hydraulic valve may include an inlet valve (IV) and an outlet valve (OV) of a hydraulic brake.

[0058] When the vehicle is in standby parking mode, the hydraulic valves at the inlet and outlet of the brake of the target wheel are locked by controlling the opening and closing of the directional control valve, thus maintaining the pressure in each wheel cylinder and realizing the parking brake function. The safety and robustness of the entire system are greatly enhanced.

[0059] This application utilizes the parking brake within the vehicle's service braking system, enabling backup parking when the electronic parking brake system malfunctions, without adding controller components or increasing costs. This improves the overall parking system safety and ensures vehicle operation. Furthermore, while existing parking brake systems only lock the left and right rear wheels, the backup parking method in this application can achieve parking with up to four wheels, including the left and right rear wheels, the left and right front wheels. This allows the vehicle to have greater parking force to meet more complex operating conditions when the EPB system fails, improving parking stability and reliability.

[0060] Next, refer to Figure 3 This application describes a backup parking method according to an embodiment of the present application.

[0061] According to one embodiment of this application, the backup parking method includes the following steps S310 and S320.

[0062] In step S310, the service braking system responds to the received fault information by obtaining parking status information from the electronic parking brake system.

[0063] When the fault detection circuit detects a fault in the EPB, the service braking system 120 obtains parking status information from the electronic parking brake system. This parking status information can be EPB switch position information.

[0064] In step S320, based on fault information and parking status information, the hydraulic system is controlled to provide parking braking pressure to the hydraulic brakes of the target wheels and lock the corresponding hydraulic valves to achieve parking.

[0065] In this application, parking braking can be performed through the service braking system. Specifically, the controller calculates the required braking force by combining other sensor parameters, and then the motor pushes the brake fluid to provide parking braking pressure to the hydraulic brake, and locks the corresponding hydraulic valve to achieve parking.

[0066] The locked hydraulic valves include all hydraulic valves in the hydraulic brake's inlet and outlet passages. Figure 2 Taking the hydraulic system shown as an example, it can lock 4 IVs and 4 OVs, or lock CSV1, CSV2, PSV1, PSV2 and 4 OV hydraulic valves.

[0067] According to one embodiment of this application, the service braking system for implementing the backup parking method can be an Integrated Power Brake (IPB) system. The IPB is a decoupled electro-hydraulic braking system that integrates the functions of a vacuum booster, an electronic vacuum pump, and an Anti-lock Braking System (ABS) / Electronic Stability Controller (ESC). The integrated power brake system includes an IPB controller, a servo-assisted motor, hydraulic valves, a master cylinder, and a brake fluid reservoir. The IPB controller is electrically connected to the EPB fault detection circuit and the servo-assisted motor. The servo-assisted motor is also connected to the master cylinder via a mechanical transmission component. The master cylinder is connected to the hydraulic valves, the brake fluid reservoir, and the hydraulic brakes of each wheel. The IPB controller controls the servo-assisted motor to drive the master cylinder to generate parking brake pressure and controls the opening and closing of the hydraulic valves. The servo-assisted motor, under the control of the IPB controller, drives the master cylinder to generate parking brake pressure.

[0068] In this embodiment, without adding other controllers, the IPB system utilizes the hydraulic pressure of the braking system to close the inlet and outlet valves at the wheel end through braking pressure, thus storing the braking pressure at the caliper. This ensures that even in the event of an actuator failure, safe parking can still be achieved without the need for additional software integration.

[0069] According to one embodiment of this application, the IPB controller can also be connected to one or more of the following via a vehicle bus: pedal depth sensor, wheel speed sensor, body control module, inertial measurement unit controller, gear position controller, and motor controller.

[0070] The IPB controller acquires pedal depth signals via a pedal depth sensor, wheel speed signals via a wheel speed sensor, vehicle inertial measurement unit (IMU) signals via an inertial measurement unit (IMU), vehicle gear information via a gear position controller, and drive shaft motor speed information via a motor controller. Combining this with current operating conditions and driver requirements, it controls the braking pressure of each wheel to achieve braking functions, including anti-lock braking, traction control, and vehicle stability control. Furthermore, by collecting information such as the driver's brake pedal depth, wheel speeds, and current gear, it can also provide more reference information for parking brake application.

[0071] It should be noted that the IPB controller in this application can also be directly connected to the motor speed sensor, gear sensor, and inertial measurement unit to obtain sensor acquisition signals carrying relevant information. This embodiment does not limit the method of information acquisition.

[0072] The inertial measurement unit (IMU) controller is installed in the vehicle and primarily collects information from sensors such as lateral acceleration, longitudinal acceleration, and yaw rate. This information is then transmitted to the vehicle's common CAN bus for other modules to receive. Wheel motor speed sensors collect the rotational speed of the corresponding motor in each wheel and connect to the corresponding electronic control unit (ECU), allowing the ECU to obtain the actual rotational speed of the motor and send the speed signal to the vehicle controller. The gear selector controller collects the current driver and vehicle gear position information and sends it to the vehicle's CAN bus. Wheel speed sensors collect the rotational speed of each wheel and connect to the vehicle stability controller, allowing the ECU to obtain the actual rotational speed of the current wheel and send the speed signal to the vehicle controller.

[0073] In addition, the IPB controller can also connect to the resolver sensors of each motor, and measure the minute rotation direction and amount of rotation of each drive motor through the sensor body, head and measuring device, and feed this information back to the control system.

[0074] The following is for reference Figure 4 This diagram illustrates the principle of locking the corresponding hydraulic valve during parking brake operation in a backup parking method according to an embodiment of this application. The × symbol in the diagram indicates hydraulic shut-off. Figure 4 As shown, when the parking brake is applied, it is first determined whether the current braking pressure meets the parking force. If it does, CSV1, CSV2, PSV1, PSV2 and the four OVs are locked to achieve parking brake.

[0075] By using the backup parking method, parking backup can be achieved without increasing the cost of PBC software integration and hardware by utilizing the existing vehicle service braking system. When the actuator motor and actuator wiring harness circuit fail, parking can be achieved through hydraulic braking to meet vehicle parking safety requirements. Furthermore, this method can achieve four-wheel braking parking, with a greater braking force than that provided by simple rear axle braking, resulting in higher safety and robustness.

[0076] According to one embodiment of this application, controlling the hydraulic system to provide parking brake pressure to the hydraulic brake of the target wheel includes:

[0077] When a brake pedal signal is detected, the hydraulic system is controlled to provide parking brake pressure to the hydraulic brakes of the target wheel, based on the brake pedal signal.

[0078] The braking pressure corresponding to the brake pedal signal here should meet the braking force requirements for parking. The braking force required for parking can be determined based on motor speed, wheel speed, and gradient.

[0079] According to one embodiment of this application, based on a brake pedal signal, controlling a hydraulic system to provide parking brake pressure to the hydraulic brake of a target wheel includes:

[0080] When the braking force corresponding to the current brake pedal signal meets the parking requirements, the hydraulic system is controlled to provide parking braking pressure to the hydraulic brakes of the target wheel according to the current braking force.

[0081] When the braking force corresponding to the current brake pedal signal is insufficient to meet the parking requirements, a prompt signal is sent to remind the user to increase the depth of the brake pedal so that the braking force corresponding to the brake pedal signal meets the parking requirements.

[0082] Please see Figure 5 In one specific implementation, the steps of generating hydraulic system control signals to provide parking brake pressure to the hydraulic brakes of the target wheels include:

[0083] S1. Collect the current pedal depth information;

[0084] S2. Determine the current braking force based on pedal depth information;

[0085] S3. Compare the current braking force with the parking braking force;

[0086] S4. When the current braking force is greater than or equal to the parking braking force, determine that the braking force corresponding to the current brake pedal signal meets the parking requirements, and generate a corresponding control signal based on the current braking force.

[0087] S5. When the current braking force is less than the parking braking force, determine that the braking force corresponding to the current brake pedal signal does not meet the parking requirements, generate braking depth prompt information, and return to step S1.

[0088] In step S1, the pedal depth information is obtained by acquiring the original braking depth signal.

[0089] In step S3, the parking braking force can be determined based on real-time collected brake fluid pressure signals, wheel speed signals, vehicle inertia signals, current vehicle gear, and motor speed.

[0090] By acquiring information signals such as motor speed, wheel speed, and vehicle gear, and calculating the current slope value of the vehicle using a slope sensor, the parking braking force is determined. This locks the brake valves of the wheels, maintaining pressure in each wheel cylinder to achieve the parking braking function. The safety and robustness of the entire system are greatly enhanced, and it meets the requirements for parking on slopes. Verification has shown that the method in this embodiment can achieve parking safety on slopes of at least 8%.

[0091] In step S5, the prompt message is used to remind the driver to increase the braking depth. The braking depth prompt message can be displayed on the instrument panel or PAD, or it can be prompted by voice. For example, the prompt message can be "increase braking depth".

[0092] According to one embodiment of this application, the method for obtaining parking status information includes:

[0093] Parking status information is obtained from the electronic parking brake system and / or the parking button.

[0094] According to one embodiment of this application, the method further includes: generating maintenance prompt information for the electronic parking brake system based on fault detection information.

[0095] The notification message can remind the driver to have the parking brake system checked as soon as possible.

[0096] According to one embodiment of this application, when the target wheel is driven by the motor distribution, the backup parking method further includes: determining the hydraulic leakage during hydraulic parking based on the rear axle motor rotation angle signal, the rear axle wheel speed direction and pulse value; and controlling the hydraulic system to pressurize when the leakage exceeds a preset leakage threshold.

[0097] The rear axle motor resolver angle signal can be acquired by a resolver sensor, and the rear axle wheel speed direction and pulse value can be acquired by a wheel speed sensor.

[0098] When the leakage exceeds the preset leakage threshold, the hydraulic system is pressurized to prevent the vehicle from rolling away and further improve parking safety.

[0099] According to one embodiment of this application, the method further includes: acquiring voltage information of the low-voltage battery; and when the voltage information is lower than a preset voltage threshold, starting the power battery to charge the low-voltage battery.

[0100] The battery will continue to consume power while the vehicle is parked. Therefore, an intelligent power protection strategy is used to monitor the low voltage of the battery. When the voltage drops below a threshold, the power battery will be activated to maintain the battery voltage.

[0101] By monitoring battery power and charging it in a timely manner, parking failure caused by battery depletion can be avoided, further improving parking safety.

[0102] According to one embodiment of this application, before controlling the hydraulic system to provide parking brake pressure to the hydraulic brake of the target wheel based on fault information and parking status information of the electronic parking brake system, the backup parking method further includes:

[0103] Perform fault detection on the electronic parking brake system;

[0104] When a preset fault is detected, corresponding fault information is generated.

[0105] In one specific implementation, fault detection circuitry can be used to detect faults in the electronic parking brake system.

[0106] The fault detection circuit can detect faults in the actuators of the vehicle's electronic parking brake system, such as faulty return loop harness, faulty EPB actuator motor, and motor faults, but is not limited to these.

[0107] The fault detection circuit performs fault detection on the vehicle's electronic parking brake system to obtain fault information of the vehicle's electronic parking brake system, and sends the fault information to the service brake system.

[0108] For example, the fault detection circuit may include an EPB motor speed detection circuit, a temperature detection circuit, etc. In specific implementation, the motor speed and temperature can be detected in real time by various corresponding sensors, and the information is transmitted to the controller of the vehicle braking system. The vehicle braking system receives the fault information and compares the fault information with preset information. When the detected information exceeds the corresponding preset range, the EPB motor is determined to be faulty.

[0109] According to one embodiment of this application, the preset fault includes one or more of the following: power supply fault, motor fault, return loop harness fault, and left and right execution circuit fault.

[0110] Specifically, a power supply failure in the electronic parking brake system may include:

[0111] The power supply voltage of the electronic parking brake system is lower than the first voltage threshold u1 and continues to exceed the first time threshold t1.

[0112] The power supply voltage of the electronic parking brake system is higher than the second voltage threshold u2 and continues to exceed the second time threshold t2.

[0113] Specifically, faults in the left and right execution circuits may include:

[0114] Both calipers detected an open circuit or a broken circuit.

[0115] Short circuits were detected on both the left and right sides;

[0116] The loop impedance was detected to be higher than the impedance threshold on both the left and right sides, and the duration exceeded the third time threshold t3.

[0117] The rear axle motor's resolver angle is greater than the angle threshold.

[0118] The difference in the number of directional pulses from the rear axle wheel speed sensor is greater than the pulse count threshold.

[0119] During EPB parking, the plunger pump pressure change is less than the pressure threshold.

[0120] If any of the above conditions are met, the EPB system can be considered unable to meet the parking requirements.

[0121] It should be noted that the above thresholds are all optimal thresholds determined in advance based on controller selection, physical characteristics, and vehicle parameters.

[0122] Based on the above fault information, parking braking can meet the parking redundancy backup requirements under various EPB parking failures, and greatly reduce the probability of braking system failure caused by wiring harness circuit, EPB controller, and EPB actuator motor failure.

[0123] It should be noted that when an EPB malfunction is detected, the following conditions must be met simultaneously before backup parking can be performed:

[0124] Vehicle speed < 3 km / h;

[0125] The gear is in P / N position;

[0126] The drive shaft motor speed is less than the speed threshold.

[0127] There is no hardware fault in the vehicle's braking system.

[0128] Next, refer to Figure 6 This paper describes the implementation process of a backup parking method according to an embodiment of the present application. In this embodiment, the service braking system is an IPB system.

[0129] like Figure 6 As shown, the implementation process includes the following steps S01-S09.

[0130] S01. After the vehicle is powered on (IG on), confirm that the EPB caliper has been released.

[0131] S02. Determine parking intent: When the vehicle is in a prohibited state, the driver presses the brake pedal and triggers the EPB switch or PAD button, requesting the EPB to clamp the parking mechanism.

[0132] S03, EPB checks the system status. It comprehensively judges the EPB parking execution status by considering three conditions: rear axle wheel speed direction, rear axle motor rotation angle, and plunger pump pressure change. It executes EPB clamping and sends out the execution result, which is displayed on the instrument panel as a parking indicator light. When an EPB system fault is detected, causing parking to fail, the EPB system status is sent to the vehicle CAN and an IPB is requested to perform hydraulic backup.

[0133] S04. After receiving the EPB backup parking request, IPB begins to check the current vehicle gear, four-wheel wheel speed & vehicle speed, and drive shaft motor speed. Once the conditions are met, IPB confirms that there are no faults.

[0134] S05. Compare the current wheel cylinder pressure P0 with the required wheel cylinder pressure P1 calculated based on the slope value of the vehicle's actual stopping position. When P0 > P1, close the CSV and PSV valves and send out parking information, indicating that the vehicle has been put into emergency parking and reminding the driver to check the parking brake system. When P0 < P1, remind the driver to increase the braking depth through the instrument panel. When the conditions are met, close the CSV and PSV valves and send out parking information, indicating that the vehicle has been put into emergency parking and reminding the driver to check the parking system.

[0135] S06. If the instrument panel continues to display a warning for 30 seconds after the vehicle is powered off, please inspect the parking brake system.

[0136] S07. During hydraulic parking, the IPB uses the rear axle motor rotation angle signal, rear axle wheel speed direction and pulse value to help determine the amount of hydraulic leakage during hydraulic parking. When the leakage exceeds the threshold, the IPB actively increases the pressure to ensure vehicle parking safety.

[0137] S08 and IPB continuously consume battery power during parking. To address this, an intelligent power-saving strategy has been added, which monitors the voltage of the smaller battery and activates the larger battery to maintain the battery voltage when it falls below a threshold.

[0138] S09. When the vehicle is powered on again (IG on), the brake pedal needs to be pressed to power on the entire vehicle. After power is on, the instrument panel will indicate to the driver that the emergency parking brake system has been released. Please be aware of the risk of the vehicle rolling away and have the parking brake system inspected as soon as possible.

[0139] The working process of the hydraulic system in the above process

[0140] In this embodiment, when the vehicle's EPB system malfunctions and cannot achieve parking on both sides, it requests the IPB to perform backup parking brake. The IPB obtains the status of each wheel and the overall vehicle status, generates corresponding braking pressure by having the driver press the brake, and then adds corresponding control logic to the IPB. By using the CSV and PSV valves in the IPB hardware, it locks the wheel cylinder pressure to generate four-wheel braking force, thereby achieving the purpose of hydraulic backup parking.

[0141] This application also provides a control device, which includes a memory and a processor. The memory stores a computer program that is executed by the processor. When the computer program is executed by the processor, it causes the control device equipped with the processor to perform the backup parking method as described in any of the above embodiments.

[0142] This application also provides a storage medium storing a computer program that runs on a computer. When the computer program runs, it causes the computer to execute the backup parking method as described in any of the above embodiments.

[0143] This application also provides a vehicle, which includes: a control device as described in any of the above embodiments, or a storage medium as described in any of the above embodiments.

[0144] Although exemplary embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above exemplary embodiments are merely illustrative and are not intended to limit the scope of the invention. Various changes and modifications can be made therein by those skilled in the art without departing from the scope and spirit of the invention. All such changes and modifications are intended to be included within the scope of the invention as claimed in the appended claims.

[0145] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0146] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed.

[0147] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0148] Similarly, it should be understood that, in order to streamline the invention and aid in understanding one or more of the various aspects of the invention, features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof in the description of exemplary embodiments of the invention. However, this inventive approach should not be construed as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as reflected in the corresponding claims, its inventive point lies in solving the corresponding technical problem with fewer features than all of those in a single disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of the invention.

[0149] Those skilled in the art will understand that, apart from the mutual exclusion of features, all features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all processes or elements of any method or apparatus so disclosed can be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) may be replaced by an alternative feature serving the same, equivalent, or similar purpose.

[0150] Furthermore, those skilled in the art will understand that although some embodiments described herein include certain features but not others included in other embodiments, combinations of features from different embodiments are intended to be within the scope of the invention and form different embodiments. For example, in the claims, any of the claimed embodiments can be used in any combination.

[0151] The various component embodiments of the present invention can be implemented in hardware, or as software modules running on one or more processors, or a combination thereof. Those skilled in the art will understand that microprocessors or digital signal processors (DSPs) can be used in practice to implement some or all of the functions of some modules in the article analysis device according to embodiments of the present invention. The present invention can also be implemented as an apparatus program (e.g., a computer program and computer program product) for performing part or all of the methods described herein. Such programs implementing the present invention can be stored on a computer-readable medium, or can be in the form of one or more signals. Such signals can be downloaded from an Internet website, provided on a carrier signal, or provided in any other form.

[0152] It should be noted that the above embodiments are illustrative of the invention and not restrictive, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The invention can be implemented by means of hardware comprising several different elements and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

[0153] The above description is merely a specific embodiment of the present invention or an explanation of that embodiment. The scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. The scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A backup parking method, characterized in that, The backup parking method includes: Based on the fault information and parking status information of the electronic parking brake system, the hydraulic system is controlled to provide parking brake pressure to the hydraulic brakes of the target wheels and lock the corresponding hydraulic valves to achieve parking. The control hydraulic system provides parking brake pressure to the hydraulic brake of the target wheel, including: when a brake pedal signal is detected, controlling the hydraulic system to provide parking brake pressure to the hydraulic brake of the target wheel according to the brake pedal signal; Specifically, based on the brake pedal signal, controlling the hydraulic system to provide parking brake pressure to the hydraulic brakes of the target wheel includes: determining whether the braking force corresponding to the current brake pedal signal meets the parking requirements, wherein the parking brake force is determined based on motor speed, wheel speed, and slope value; when the braking force corresponding to the current brake pedal signal is greater than or equal to the parking brake force, it is determined that the braking force corresponding to the current brake pedal signal meets the parking requirements, and the hydraulic system is controlled to provide parking brake pressure to the hydraulic brakes of the target wheel based on the current braking force; when the braking force corresponding to the current brake pedal signal is less than the parking brake force, it is determined that the braking force corresponding to the current brake pedal signal does not meet the parking requirements, and a prompt signal is sent to prompt the user to increase the brake pedal depth so that the braking force corresponding to the brake pedal signal meets the parking requirements.

2. The backup parking method as described in claim 1, characterized in that, The method for obtaining the parking status information includes: Parking status information is obtained from the electronic parking brake system and / or the parking button.

3. The backup parking method as described in claim 1, characterized in that, When the target wheels are driven by distributed motors, the backup parking method further includes: Based on the rear axle motor resolver angle signal, rear axle wheel speed direction and pulse value, the hydraulic leakage during hydraulic parking is determined; When the leakage amount exceeds a preset leakage threshold, the hydraulic system is pressurized.

4. The backup parking method as described in claim 1, characterized in that, The backup parking method also includes: Obtain the voltage information of the low-voltage battery; When the voltage information is lower than a preset voltage threshold, the power battery is activated to charge the low-voltage battery.

5. The backup parking method as described in claim 1, characterized in that, Before controlling the hydraulic system to provide parking brake pressure to the hydraulic brakes of the target wheels based on fault information and parking status information of the electronic parking brake system, the backup parking method further includes: Fault detection was performed on the electronic parking brake system. When a preset fault is detected, corresponding fault information is generated.

6. The backup parking method as described in claim 5, characterized in that, The preset faults include one or more of the following: power supply fault, motor fault, return loop harness fault, and left and right execution circuit fault.

7. A control device, characterized in that, The control device includes a memory and a processor, the memory storing a computer program executed by the processor, the computer program, when executed by the processor, causing the control device on which the processor is installed to perform the backup parking method as described in any one of claims 1-6.

8. A storage medium, characterized in that, The storage medium stores a computer program that runs on a computer and, when running, causes the computer to perform the backup parking method as described in any one of claims 1-6.

9. A vehicle, characterized in that, The vehicles include: The control device as described in claim 7, or, The storage medium as described in claim 8.

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