Backup parking method and device, medium and vehicle

Abstract

The invention provides a backup parking method and device, a medium and a vehicle. The backup parking method comprises the steps that based on fault information and parking state information of an electronic parking braking system, a hydraulic system is controlled to provide parking braking pressure for a hydraulic brake of a target wheel, and a corresponding hydraulic valve is locked to achieve parking. According to the method, hydraulic backup parking can be achieved through an existing vehicle service braking system when the electronic parking braking system breaks down, implementation is easy, and the requirement for vehicle parking safety is met.

Description

Technical Field

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

[0002] In the related art, the brake backup control system usually integrates the electronic parking brake system (EPB) software into two electronic control units (ECU). When the main control ECU fails, the other ECU controls the motor to achieve single-side or double-side parking to meet the parking backup requirements. The above solution needs to consider the requirements of multi-ECU interaction and controller integration. Both the cost of single-vehicle implementation and the technical complexity are relatively high. When the EPB motor hardware fails, this hardware actuator has no backup and the parking failure problem may still occur. Summary of the invention

[0003] The present application is proposed in view of the above problems. The present application provides a backup parking method, device, medium and vehicle, which can utilize the existing vehicle service brake system to realize hydraulic backup parking when the electronic parking brake system fails, is easy to realize and meets the parking safety of the vehicle.

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

[0005] 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.

[0006] In one embodiment of the present application, controlling the hydraulic system to provide parking brake pressure for 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 brake of the target wheel according to the brake pedal signal.

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

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

[0010] When the braking force corresponding to the current brake pedal signal does not meet the parking requirement, 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 requirement.

[0011] In one embodiment of the present application, according to the brake pedal signal, controlling the hydraulic system to provide parking brake pressure for the hydraulic brake of the target wheel also includes:

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

[0013] When the braking force corresponding to the current brake pedal signal is greater than or equal to the parking brake force, determining that the braking force corresponding to the current brake pedal signal meets the parking requirement, wherein the parking brake force is determined based on the motor speed, the wheel speed, and the ramp 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 requirement.

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

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

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

[0018] Determine the hydraulic leakage during hydraulic parking execution based on the rear axle motor rotation angle signal, rear axle wheel speed direction and pulse value;

[0019] When the leakage amount is greater than a preset leakage amount threshold, the hydraulic system is controlled to increase pressure.

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

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

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

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

[0024] Performing fault detection on the electronic parking brake system;

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

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

[0027] According to a second aspect of the present application, a control device is provided, which includes a memory and a processor, wherein the memory stores a computer program executed by the processor, and when the computer program is executed by the processor, the control device equipped with the processor executes the backup parking method as described in any one of the first aspects above.

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

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

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

[0031] A storage medium as described in any one of the third aspects above.

[0032] The present application realizes hydraulic backup parking when the EPB fails by utilizing the existing vehicle service brake system, which is easy to realize and meets the parking safety of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The above and other purposes, features and advantages of the present invention will become more apparent by describing the embodiments of the present invention in more detail in conjunction with the accompanying drawings. The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings, the same reference numerals generally represent the same components or steps.

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

[0035] Figure 2 is a schematic diagram of hydraulic control of a service brake system during driving according to an embodiment of the present application;

[0036] Figure 3 is a schematic flow chart of a backup parking method according to an embodiment of the present application;

[0037] Figure 4 is a schematic diagram of the principle of locking the corresponding hydraulic valve during parking braking according to an embodiment of the present application;

[0038] Figure 5 is a schematic flow chart of generating a hydraulic system control signal according to an embodiment of the present application;

[0039] Figure 6 It is a schematic flowchart of a backup parking method according to another embodiment of the present application. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical scheme and advantages of the present invention more obvious, the exemplary embodiments according to the present invention will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments of the present invention, and 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 in the present invention, all other embodiments obtained by those skilled in the art without creative work should fall within the protection scope of the present invention.

[0041] Since the technical complexity of the redundant parking solution through dual backup of the controller and some actuators is relatively high, and when the EPB motor hardware fails, this hardware actuator has no backup and backup parking failure may still occur. Based on this, the present application proposes a backup parking method, equipment, medium and vehicle based on the existing service brake system.

[0042] The vehicle braking system usually includes a service brake system and a parking brake system. The parking brake system mainly includes: an operating mechanism, an electronic control unit, an actuator, and an alarm indicator light. The operating mechanism can be an EPB switch, and the actuator mainly includes an EPB caliper motor, a deceleration mechanism, a spiral rotation mechanism, a brake wheel cylinder piston, a friction plate, and a brake disc. The spiral rotation mechanism is mainly divided into two types: a threaded transmission mechanism and a ball screw transmission mechanism. The service brake system provides braking force to the wheels by controlling the hydraulic system to reduce the speed of the moving vehicle or even stop it. In this application, the hydraulic system includes a hydraulic pump, a hydraulic valve, a hydraulic cylinder, a hydraulic pipeline, and a fuel tank. The hydraulic pump is the power source of the hydraulic system, and the oil is pressed into the hydraulic pipeline and the hydraulic cylinder by mechanical means. The hydraulic valve can control the flow direction and speed of the oil, thereby realizing the control and adjustment of various parts of the car. The hydraulic cylinder is the actuator of the hydraulic system, which can convert the pressure of the oil into mechanical force to complete the movement and adjustment tasks of the car. The hydraulic pipeline plays the role of connecting various components and transferring the oil to the position that needs to be controlled. The hydraulic oil tank is the place where the hydraulic oil is stored.

[0043] First, refer to Figure 1 A vehicle braking system according to an embodiment of the present application is described.

[0044] The thick black line in the figure is the hydraulic circuit of the service brake system, the gray line is the power realization circuit, and the dotted line is the wiring harness circuit. Figure 1 As shown, the EPB controller is connected to the vehicle-mounted tablet computer (PDA) or EPB switch. The PAD is a virtual switch used to collect the driver's intention to clamp and release the EPB, and sends the collected signal 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 collect the driver's intention to clamp and release the EPB, and is connected to the EPB controller through a hard line. 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 bus (CAN, Controller Area Network), the local Internet (Local Interconnect Network, LIN) bus, etc.

[0045] The vehicle controller, as the controller of the power system, controls the power output by controlling the motor speed and torque. The motors include the left front motor, the left rear motor, the right front motor, and the right rear motor. Each motor outputs power to the left front wheel, the left rear wheel, the right front wheel, and the right rear wheel through the drive shaft. The EPB controller is used to control the left and right motors of the rear axle to realize the clamping and release of the caliper to control the parking brake. The service brake system controller realizes brake control by controlling the pressure of the hydraulic circuit of the brake. The brake can convert the brake fluid pressure established by the vehicle stability controller to control the relevant mechanism into the braking force on the wheel. The brake includes the left front brake, the left rear brake, the right front brake, and the right rear brake.

[0046] The working process of EPB usually includes: when the vehicle is stationary or the speed is lower than a certain threshold, the driver presses the parking button or operates the PDA, the EPB control unit receives the input current signal, and then calculates the clamping force required by the current vehicle after comprehensively receiving the relevant signals transmitted by other controllers or sensors, thereby outputting the target current signal to the EPB caliper motor, and the caliper motor starts to rotate to output torque, and the motor is decelerated and torque increased through the reduction mechanism to form the EPB caliper input torque, and then the EPB caliper input torque is converted into piston clamping force through threaded transmission or ball screw transmission to achieve parking, and the parking system status signal is sent to the instrument to inform the driver.

[0047] The following reference Figure 2The following is a schematic diagram of hydraulic control of a driving brake system according to an embodiment of the present application. The dashed line with an arrow in the figure is the flow direction of the brake fluid when the brake pedal is stepped on, the gray line with an arrow is the return direction of ABS activation, and the black arrow is the flow direction of the simulator hydraulic pressure. In addition to IV and OV, the valves in the figure also include a master cylinder isolation valve (Cylinder Separate Valve, CSV) used to isolate the hydraulic pressure of the master cylinder and the wheel cylinder, and a plunger isolation valve (Plunger Separate Valve, PSV) used to switch the brake hydraulic pressure source. When the PSV is closed, the brake pressure source comes from the driver, and when it is opened, the brake pressure source comes from the motor and pump. The brake fluid pot, the master cylinder, and the master cylinder simulator constitute a separate circuit. The hydraulic brakes of the left front wheel (Front Left, FL), the right front wheel (Front Right, FR), the left rear wheel (Rear Left, RL), and the right rear wheel (Rear Right, RR) are respectively connected to the hydraulic pipeline.

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

[0049] When the vehicle is powered on normally, the ignition gear is turned off and there is no fault in the EPB (both left and right cannot be parked), the master cylinder isolation valve opens, the master cylinder and wheel cylinder pressure are connected, the PSV valve isolation plunger pump is connected to the circuit, and at the same time OV, PSV1, and PSV2 are closed, the hydraulic pressure between the master cylinder and the master cylinder simulator is cut off, and mechanical backup braking is achieved. When the brake pedal is released, the hydraulic pressure of the four wheel cylinders returns to the brake fluid pot along the original route. In this case, parking is still achieved by EPB when the power is turned off.

[0050] Next, a backup parking method according to an embodiment of the present application is described in detail.

[0051] The backup parking method of this embodiment can be used to 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 and an embedded device or other forms of processing units with data processing capabilities and / or instruction execution capabilities, and can control other components in the service braking system to perform desired functions.

[0052] The method comprises: based on the fault information and parking state information of the electronic parking brake system, controlling the hydraulic system to provide parking brake pressure for the hydraulic brake of the target wheel and locking the corresponding hydraulic valve to achieve parking.

[0053] Here, the parking status information may include status information of the EPB button, such as status information of the parking button being pressed, or may be operation instruction information of the user's in-vehicle tablet computer, such as a parking instruction.

[0054] For example, the EPB controller can collect the driver's switch requirements, monitor the open circuit and short circuit status of the left and right execution circuits, and send the final system parking status information, fault information, etc. to the vehicle public CAN. Therefore, the service brake system can obtain fault information and parking status information in real time.

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

[0056] The hydraulic valve that provides parking brake pressure and locks the hydraulic brake of the target wheel can be a hydraulic valve for controlling the brake fluid to flow into and out of the target wheel brake. Specifically, the hydraulic valve includes a directional control valve through which the brake fluid flowing into and out of each wheel brake flows.

[0057] Exemplarily, the hydraulic valve may include an inlet valve (Inlet valve, IV) and an outlet valve (Outlet valve, OV) of the hydraulic brake.

[0058] During backup parking, the hydraulic valves at the brake inlet and outlet of the target wheel are locked by controlling the opening and closing of the directional control valve, maintaining pressure in each wheel cylinder to achieve the parking brake function, greatly enhancing the safety and robustness of the entire system.

[0059] In this application, by utilizing the parking brake of the service brake system, it is possible to meet the backup parking requirements when the electronic parking brake system fails without adding controller parts and costs on the basis of existing vehicles, thereby improving the parking system safety of the entire vehicle and ensuring the driving of the vehicle. In addition, the existing parking brake system only locks the left rear wheel and the right rear wheel to achieve parking, while the backup parking method in this application can achieve four-wheel parking including the left rear wheel, the right rear wheel, the left front wheel, and the right front wheel at most, so that the vehicle can have greater parking force to meet more complex working conditions when the EPB system fails, and improve the stability and reliability of parking.

[0060] Next, refer to Figure 3 A backup parking method according to an embodiment of the present application is described below.

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

[0062] In step S310 , the service brake system obtains parking state information from the electronic parking brake system in response to the received fault information.

[0063] When the fault detection circuit detects that the EPB fails, the service brake system 120 obtains parking state information from the electronic parking brake system, where the parking state information may be EPB switch position information.

[0064] In step S320, based on the fault information and the parking state information, 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.

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

[0066] The locked hydraulic valves include all the hydraulic valves on the hydraulic brake inlet and outlet passages. Figure 2 Taking the hydraulic system shown as an example, 4 IVs and 4 OVs can be locked, and CSV1, CSV2, PSV1, PSV2 and 4 OV hydraulic valves can also be locked.

[0067] According to one embodiment of the present application, the service brake system for implementing the backup parking method may be an intelligent integrated brake system (Integrated Power Brake, IPB), which belongs to a decoupled electro-hydraulic brake system, integrating product functions such as a vacuum booster, an electronic vacuum pump, and an anti-lock braking system (ABS) / electronic stability control system (ESC). The intelligent integrated brake system includes an IPB controller, a servo booster motor, a hydraulic valve, a master cylinder, and a brake fluid pot. The IPB controller is electrically connected to an EPB fault detection circuit and a servo booster motor respectively. The servo booster motor is also connected to the master cylinder through a mechanical transmission component. The master cylinder is connected to the hydraulic valve, the brake fluid pot, and the hydraulic brake of each wheel respectively; the IPB controller is used to control the servo booster motor to drive the master cylinder to generate parking brake pressure and control the opening and closing of the hydraulic valve; the servo booster motor is used to drive the master cylinder to generate parking brake pressure under the control of the IPB controller.

[0068] In this embodiment, without adding other controllers, the IPB system uses the brake system hydraulic pressure to close the wheel end inlet and outlet valves through the brake pressure, and stores the brake pressure at the caliper to ensure safe parking when an actuator failure occurs, without the need for additional integrated software.

[0069] According to one embodiment of the present application, the IPB controller may also be connected to one or more of a pedal depth sensor, a wheel speed sensor, a body control module, an inertial measurement unit controller, a gear controller, and a motor controller through a vehicle bus.

[0070] The IPB controller can obtain the pedal depth signal by connecting with the pedal depth sensor, the wheel speed signal by the wheel speed sensor, the vehicle body inertial measurement signal by the inertial measurement unit, the vehicle gear information by the gear controller, and the drive shaft motor speed information by the motor controller. It controls the brake pressure of each wheel in combination with the current working conditions and the driver's needs to realize the braking function, which includes the main functions of wheel anti-lock, traction control, and body stability control. In addition, by collecting information such as the driver's brake pedal depth, the four wheel speeds, and the current driving gear, it can also provide more reference information for parking brakes.

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

[0072] The inertial measurement unit controller is a controller installed on the vehicle. It mainly collects information such as the vehicle's lateral acceleration, longitudinal acceleration, and yaw rate sensor, and sends this signal to the vehicle's public CAN for other modules to receive and use. The motor speed sensor of each wheel is responsible for collecting the speed of the corresponding motor of each wheel, and is connected to the corresponding electronic control so that the electronic control can obtain the actual speed of the current motor and send the speed signal to the vehicle controller. The gear controller is responsible for collecting the current driver and vehicle gear information and sending it to the vehicle CAN bus. The wheel speed sensor of each wheel is responsible for collecting the speed of each wheel and is connected to the vehicle stability controller so that the vehicle stability controller can obtain the actual speed of the current wheel and send the speed signal to the vehicle controller.

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

[0074] The following reference Figure 4 The schematic diagram of the principle of locking the corresponding hydraulic valve during parking brake in the backup parking method according to an embodiment of the present application is described below. The × in the figure indicates hydraulic shutoff. Figure 4 As shown, when parking brake is applied, first determine whether the current brake pressure meets the parking force. If so, CSV1, CSV2, PSV1, PSV2 and 4 OVs are locked to achieve parking brake.

[0075] By using the backup parking method and the existing vehicle service brake system, parking backup can be achieved without increasing the PBC software integration and hardware costs; when the actuator motor and the actuator harness circuit fail, parking is achieved through hydraulic braking to meet the parking safety of the vehicle; and this method can achieve four-wheel braking parking, and the braking force is greater than the parking force provided by the simple rear axle brake, and is safer and more robust.

[0076] According to one embodiment of the present application, controlling the hydraulic system to provide parking brake pressure for 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 wheels according to the brake pedal signal.

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

[0079] According to one embodiment of the present application, controlling the hydraulic system to provide parking brake pressure for the hydraulic brake of the target wheel according to the brake pedal signal includes:

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

[0081] When the braking force corresponding to the current brake pedal signal does not meet the parking requirement, 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 requirement.

[0082] See also Figure 5 In one specific implementation, the step of generating a hydraulic system control signal to provide a parking brake pressure to a hydraulic brake of a target wheel includes:

[0083] S1, collecting current pedal depth information;

[0084] S2, determining the current braking force based on the pedal depth information;

[0085] S3, comparing 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, determining that the braking force corresponding to the current brake pedal signal meets the parking requirement, and generating a corresponding control signal based on the current braking force;

[0087] S5. When the current braking force 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 requirement, a braking depth prompt message is generated, and the process returns to step S1.

[0088] In step S1, pedal depth information is obtained by collecting a raw signal of brake depth.

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

[0090] By obtaining information signals such as motor speed, wheel speed and vehicle gear position, and calculating the current slope value of the vehicle through the slope sensor, the parking brake force is determined, so that the brake inlet and outlet valves that lock the wheels will maintain the pressure in each wheel cylinder to achieve the parking brake function, and the safety and robustness of the entire system are greatly enhanced; and it meets the needs of slope parking. It has been verified that the method of this embodiment can achieve a minimum of 8% slope parking safety.

[0091] In step S5, the prompt information is used to remind the driver to increase the braking depth. The braking depth prompt information can be displayed through the instrument or PAD, and can also be prompted by voice. For example, the prompt information can be "increase braking depth".

[0092] According to one embodiment of the present application, a method for acquiring parking status information includes:

[0093] Obtain parking status information from the electric parking brake system and / or the parking button.

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

[0095] The prompt message can remind the driver to inspect the parking brake system as soon as possible.

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

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

[0098] When the leakage volume is greater than the preset leakage volume threshold, the hydraulic system is controlled to increase pressure, which can prevent the vehicle from rolling down the slope and further improve the safety of parking.

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

[0100] The battery power will continue to be consumed during parking, so an intelligent power conservation strategy is used to monitor the low-voltage battery voltage. When it is lower than the threshold, the power battery is started to supply power to maintain the battery voltage.

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

[0102] According to one embodiment of the present application, before controlling the hydraulic system to provide parking brake pressure for the hydraulic brake of the target wheel based on the fault information and parking state 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 a specific implementation, the electronic parking brake system may be fault-detected by a fault detection circuit.

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

[0107] The fault detection circuit performs fault detection on the vehicle electronic parking brake system to obtain fault information of the vehicle 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 a specific implementation, the motor speed and temperature can be detected in real time through various corresponding sensors, and the information can be transmitted to the controller of the service brake system. The service brake system receives the fault information and compares the fault information with the preset information. When the detection information exceeds the corresponding preset range, the EPB motor is determined to be faulty.

[0109] According to one embodiment of the present application, the preset faults include one or more of power supply faults, motor faults, loop harness faults, and left and right execution circuit faults.

[0110] Specifically, the power supply failure of 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 supply voltage of the electronic parking brake system is higher than the second voltage threshold u2 and lasts longer than the second time threshold t2.

[0113] Specifically, left and right execution circuit failures may include:

[0114] The calipers on both sides detected an open circuit or a broken circuit;

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

[0116] The loop impedance detected on the left and right sides is higher than the impedance threshold and lasts longer than the third time threshold t3;

[0117] The rear axle motor rotation angle is greater than the angle threshold;

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

[0119] The plunger pump pressure change during the EPB parking process is less than the pressure threshold.

[0120] When any of the above conditions is met, it can be considered that the EPB system cannot meet the parking requirement.

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

[0122] Parking braking based on the above fault information can meet the parking redundancy backup requirements under various EPB parking failures, greatly reducing the probability of vehicle braking system failure due to wiring harness circuit, EPB controller, and EPB execution motor failure.

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

[0124] Vehicle speed: <3 km / h;

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

[0126] The driving shaft motor speed is less than the speed threshold;

[0127] There is no hardware failure in the service brake system.

[0128] Next, refer to Figure 6 The implementation process of the backup parking method according to an embodiment of the present application is described below. In this embodiment, the service brake 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 and the ignition gear (IG on) is turned on, confirm that the EPB caliper has been released.

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

[0132] S03, EPB checks the system status, and comprehensively judges the execution status of EPB parking through three conditions: rear axle wheel speed direction, rear axle motor rotation angle, and plunger pump pressure change. It executes EPB clamping and sends the execution result, and the parking indicator light is displayed on the instrument; when an EPB system fault is detected, resulting in parking failure, the EPB system status is sent to the vehicle CAN, and IPB is requested for hydraulic backup.

[0133] S04. After receiving the EPB backup parking request, IPB starts to detect the current vehicle gear position, four-wheel speed, vehicle speed, and drive shaft motor speed status. When the conditions are met, it is confirmed that IPB should be fault-free.

[0134] S05. Compare the current wheel cylinder pressure P0 with the required wheel cylinder pressure P1 calculated according to the slope value of the actual parking position of the vehicle. When P0>P1, close the CSV and PSV valves to send out the parking information, indicating that the vehicle has been parked in an emergency and remind the driver to inspect the parking brake system. When P0<P1, remind the driver through the instrument to increase the braking depth. When the conditions are met, close the CSV and PSV valves, send out the parking information, indicating that the vehicle has been parked in an emergency and remind the driver to inspect the parking system.

[0135] S06. After the vehicle is powered off, the instrument panel will continue to remind you for 30 seconds. Please inspect the parking brake system.

[0136] S07. During hydraulic parking, IPB assists in determining the amount of hydraulic leakage during hydraulic parking through the rear axle motor rotation angle signal, rear axle wheel speed direction and pulse value. When the leakage is greater than the threshold, IPB actively increases pressure to ensure vehicle parking safety.

[0137] S08 and IPB will continue to consume battery power during parking. An intelligent power conservation strategy has been added to monitor the small battery voltage. When it is lower than the threshold, the large battery is started to supply power to maintain the battery voltage.

[0138] S09. When the vehicle is powered on again, you need to step on the brake pedal to power on the vehicle. After powering on, the instrument prompts the driver that the emergency parking brake system has been released. Please pay attention to the risk of rolling and repair the parking brake system as soon as possible.

[0139] In the above process, the working process of the hydraulic system

[0140] In this embodiment, when the vehicle's EPB system fails and parking on both sides cannot be achieved, the IPB is requested to perform backup parking brakes. The IPB obtains the status of each wheel and the status of the entire vehicle, generates corresponding braking pressure by the driver stepping on the brakes, and then increases the corresponding control logic of the IPB, uses the CSV and PSV valves in the IPB hardware, locks the wheel cylinder pressure to generate four-wheel braking force, and achieves the purpose of hydraulic backup parking.

[0141] An embodiment of the present application also provides a control device, which includes a memory and a processor. The memory stores a computer program executed by the processor. When the computer program is executed by the processor, the control device equipped with the processor executes the backup parking method of any of the above embodiments.

[0142] An embodiment of the present application further provides a storage medium, on which a computer program is stored. The computer program runs on a computer, and when the computer program is running, the computer executes the backup parking method of any of the above embodiments.

[0143] An embodiment of the present application also provides a vehicle, the vehicle comprising: a control device as in any of the above embodiments, or a storage medium as in any of the above embodiments.

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

[0145] Those skilled in the art will appreciate that the units and algorithm steps of each example 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 performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present 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 only schematic, for example, the division of the units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed.

[0147] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0148] Similarly, it should be understood that in order to streamline the present invention and help understand one or more of the various inventive aspects, in the description of the exemplary embodiments of the present invention, the various features of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. However, this inventive method should not be interpreted as reflecting the following intention: the claimed invention requires more features than the features explicitly stated in each claim. More specifically, as reflected in the corresponding claims, the inventive point is that the corresponding technical problem can be solved with less than all the features of a single disclosed embodiment. Therefore, the claims following the specific embodiment are hereby expressly incorporated into the specific embodiment, wherein each claim itself serves as a separate embodiment of the present invention.

[0149] It will be understood by those skilled in the art that, except for mutually exclusive features, all features disclosed in this specification (including the accompanying claims, abstracts and drawings) and all processes or units of any method or device disclosed in this specification may be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstracts and drawings) may be replaced by an alternative feature that provides the same, equivalent or similar purpose.

[0150] In addition, those skilled in the art will appreciate that, although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present invention and form different embodiments. For example, in the claims, any one of the claimed embodiments may be used in any combination.

[0151] The various component embodiments of the present invention may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. It should be understood by those skilled in the art that a microprocessor or digital signal processor (DSP) may be used in practice to implement some or all of the functions of some modules in the article analysis device according to an embodiment of the present invention. The present invention may also be implemented as a device program (e.g., a computer program and a computer program product) for executing part or all of the methods described herein. Such a program implementing the present invention may be stored on a computer-readable medium, or may be in the form of one or more signals. Such a signal may be downloaded from an Internet website, or provided on a carrier signal, or provided in any other form.

[0152] It should be noted that the above embodiments illustrate the present invention rather than limit it, and that those skilled in the art may devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference symbol between brackets shall not be construed as a limitation on the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "one" or "an" preceding an element does not exclude the presence of a plurality of such elements. The present invention may be implemented by means of hardware comprising a number of different elements and by means of a suitably programmed computer. In a unit claim enumerating a number of devices, several of these devices may be embodied by the same hardware item. The use of the words first, second, and third, etc., does not indicate any order. These words may be interpreted as names.

[0153] The above is only a specific embodiment of the present invention or an explanation of a specific embodiment. The protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A backup parking method, characterized in that: The backup parking method comprises: 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.

2. The backup parking method according to claim 1, characterized in that: Control the hydraulic system to provide parking brake pressure to the hydraulic brakes of the target wheels, including: When a brake pedal signal is detected, the hydraulic system is controlled to provide parking brake pressure to the hydraulic brake of the target wheel according to the brake pedal signal.

3. The backup parking method according to claim 2, characterized in that: According to the brake pedal signal, controlling the hydraulic system to provide parking brake pressure for the hydraulic brake of the target wheel includes: When the braking force corresponding to the current brake pedal signal meets the parking requirement, the hydraulic system is controlled according to the current braking force to provide parking brake pressure for the hydraulic brake of the target wheel; When the braking force corresponding to the current brake pedal signal does not meet the parking requirement, 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 requirement.

4. The backup parking method according to claim 3, characterized in that: According to the brake pedal signal, controlling the hydraulic system to provide parking brake pressure for the hydraulic brake of the target wheel also includes: Determine whether the braking force corresponding to the current brake pedal signal meets the parking requirement; When the braking force corresponding to the current brake pedal signal is greater than or equal to the parking brake force, determining that the braking force corresponding to the current brake pedal signal meets the parking requirement, wherein the parking brake force is determined based on the motor speed, the wheel speed, and the ramp value; 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 requirement.

5. The backup parking method according to claim 1, characterized in that: The method for acquiring parking status information includes: The parking state information is obtained from the electronic parking brake system and / or the parking button.

6. The backup parking method according to claim 1, characterized in that: When the target wheels are driven by motor distribution, the backup parking method further includes: Determine the hydraulic leakage during hydraulic parking execution based on the rear axle motor rotation angle signal, rear axle wheel speed direction and pulse value; When the leakage amount is greater than a preset leakage amount threshold, the hydraulic system is controlled to increase pressure.

7. The backup parking method according to claim 1, characterized in that: The backup parking method further includes: Get the voltage information of the low-voltage battery; When the voltage information is lower than a preset voltage threshold, the power battery is started to charge the low-voltage battery.

8. The backup parking method according to claim 1, characterized in that: Before controlling the hydraulic system to provide parking brake pressure for the hydraulic brake of the target wheel based on the fault information and parking state information of the electronic parking brake system, the backup parking method further includes: Performing fault detection on the electronic parking brake system; When a preset fault is detected, corresponding fault information is generated.

9. The backup parking method according to claim 8, characterized in that: The preset faults include one or more of power supply faults, motor faults, loop harness faults, and left and right execution circuit faults.

10. A control device, characterized in that: The control device includes a memory and a processor, wherein the memory stores a computer program executed by the processor, and when the computer program is executed by the processor, the control device equipped with the processor executes the backup parking method as described in any one of claims 1 to 9.

11. A storage medium, characterized in that: The storage medium stores a computer program, which runs on a computer. When the computer program is running, the computer executes the backup parking method according to any one of claims 1 to 9.

12. A vehicle, characterized in that: The vehicle comprises: The control device as claimed in claim 10, or The storage medium as claimed in claim 11.

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