Control method and device of electronic parking system

Abstract

The invention provides a control method and device for an electronic parking system, and belongs to the technical field of parking braking. The method comprises the steps that the air chamber pressure of a brake air chamber and a vehicle state signal are obtained; determining a parking state of the electronic parking system based on the air chamber pressure, and determining an expected parking state of the electronic parking system based on the vehicle state signal; when the parking state is different from the expected parking state, a pressure adjusting signal is generated, the pressure of the air chamber is adjusted based on the pressure adjusting signal, and the vehicle is controlled to be kept in the expected parking state. When the parking state is different from the expected parking state, the vehicle is controlled to be kept in the expected parking state, unexpected parking and unexpected parking release of the vehicle are avoided, then safety accidents are avoided, and the safety of the vehicle is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of parking brakes, and in particular to a control method and device for an electronic parking system. Background Art

[0002] The handbrake of traditional commercial vehicles is mainly realized by pneumatic structure, which is simple and reliable. With the development requirements of intelligence and electrification, the electronic parking brake (EPB) system has gradually become the focus of commercial vehicle applications. Compared with the traditional handbrake, the operation method has changed to sending instructions to the EPB ECU by pressing and lifting the button switch (HCU), and the EPB ECU controls the opening and closing of the solenoid valve to achieve exhaust or intake of the brake system, thereby achieving parking brake or releasing parking.

[0003] EPB collects digital signals from HCU, calculates through ECU, and controls the actuator to achieve parking. If the HCU output signal is wrong, it is easy to cause unexpected parking or unexpected release of parking, thus causing safety accidents.

[0004] Therefore, there is an urgent need to provide a control method and device for an electronic parking system to avoid unexpected parking or unexpected release of parking caused by an erroneous HCU output signal, thereby ensuring the safety of vehicle driving. Summary of the invention

[0005] In view of this, it is necessary to provide a control method and device for an electronic parking system to solve the technical problem in the prior art that when the output signal of the electronic handbrake button switch is incorrect, unexpected parking or unexpected release of parking occurs, resulting in safety risks.

[0006] On the one hand, in order to solve the above technical problems, the present invention provides a control method of an electronic parking system, comprising: Acquire the air chamber pressure of the brake air chamber and the vehicle status signal; determining a parking state of the electronic parking system based on the air chamber pressure, and determining a desired parking state of the electronic parking system based on the vehicle state signal; When the parking state is different from the desired parking state, a pressure adjustment signal is generated, and the air chamber pressure is adjusted based on the pressure adjustment signal to control the vehicle to maintain the desired parking state.

[0007] In a possible implementation, the parking state includes parking; then determining the parking state of the electronic parking system based on the air chamber pressure includes: It is determined whether the air chamber pressure is within the parking air chamber pressure range within a first preset time, and if so, the parking state is determined to be parking.

[0008] In a possible implementation, the parking state further includes incomplete release of parking; then determining the parking state of the electronic parking system based on the air chamber pressure includes: Determining whether the air chamber pressure is less than a first pressure threshold and whether a duration for which the air chamber pressure is less than the first pressure threshold is greater than a preset duration; When the air chamber pressure is less than a first pressure threshold and a duration for which the air chamber pressure is less than the first pressure threshold is greater than a preset duration, the parking state is incompletely released.

[0009] In a possible implementation, the parking state further includes completely releasing the parking state; then determining the parking state of the electronic parking system based on the air chamber pressure includes: It is determined whether the air chamber pressure is greater than a second pressure threshold, and if so, the parking state is completely released.

[0010] In a possible implementation, the desired parking state includes parking, and the vehicle state signal includes an electronic parking brake button request signal, a transmission output shaft vehicle speed signal, a wheel speed signal, and an external system request signal; Then, determining the expected parking state of the electronic parking system based on the vehicle state signal includes: When the electronic parking brake button request signal is a parking request signal, or the transmission output shaft vehicle speed signal is zero, the wheel speed signal is zero and the external system request signal is a parking request signal, the desired parking state is parking.

[0011] In a possible implementation, the desired parking state further includes releasing parking, and the vehicle state signal further includes a brake pedal signal, an accelerator pedal signal, a transmission combined brake state signal, an engine torque signal, and a vehicle air pressure signal; Then, determining the expected parking state of the electronic parking system based on the vehicle state signal includes: When the electronic parking brake button request signal is a request to release parking, and the brake pedal signal is a pressed signal, the desired parking state is to release parking; When the accelerator pedal signal is a depressed signal, the transmission combined with the brake state signal is a released signal, the engine torque signal meets the starting torque requirement, and the vehicle air pressure signal meets the starting air pressure requirement, the expected parking state is released parking.

[0012] In a possible implementation, when the parking state is parking or completely released from parking, and the desired parking state is released from parking, adjusting the air chamber pressure based on the pressure adjustment signal includes: Controlling the air inlet valve of the brake air chamber to open, and inputting gas into the brake air chamber until the air chamber pressure of the brake air chamber reaches the reference air pressure; When the parking state is completely released from parking and the desired parking state is parking, the step of adjusting the air chamber pressure includes: The exhaust valve of the brake air chamber is controlled to open to exhaust the gas in the brake air chamber until the air chamber pressure of the brake air chamber is within the parking air chamber pressure range.

[0013] In a possible implementation, before adjusting the air chamber pressure based on the pressure adjustment signal, the method further includes: Verifying the pressure regulation signal based on an E2E verification mechanism; Then the step of adjusting the air chamber pressure comprises: When the pressure regulating signal passes the verification, the air chamber pressure is adjusted based on the pressure regulating signal.

[0014] In a possible implementation, the method further includes: Acquire a first vehicle safety level when the parking state is a request signal for an electronic handbrake button when the parking state is parked, a second vehicle safety level when the parking state is a request signal for an electronic handbrake button when the parking state is not completely released, and a third vehicle safety level when the parking state is a request signal for an electronic handbrake button when the parking state is completely released; A target vehicle safety level that is the highest among the first vehicle safety level, the second vehicle safety level, and the third vehicle safety level is determined, and the target vehicle safety level is used as the vehicle safety level of the electronic handbrake button request signal.

[0015] On the other hand, the present invention further provides a control device for an electronic parking system, comprising: A data acquisition unit, used to acquire the air chamber pressure of the brake air chamber and a vehicle status signal; a parking state determining unit, configured to determine a parking state of the electronic parking system based on the air chamber pressure, and to determine a desired parking state of the electronic parking system based on the vehicle state signal; The parking state control unit is used to generate a pressure adjustment signal when the parking state is different from the expected parking state, and adjust the air chamber pressure based on the pressure adjustment signal to control the vehicle to maintain the expected parking state.

[0016] The beneficial effects of the present invention are as follows: the control method of the electronic parking system provided by the present invention can determine the parking state issued by the button switch of the electronic handbrake based on the air chamber pressure, and determine the expected parking state based on the vehicle status signal by acquiring the air chamber pressure of the brake air chamber and the vehicle status signal; when the parking state is different from the expected parking state, a pressure adjustment signal is generated to adjust the air chamber pressure, so as to control the vehicle to maintain the expected parking state and avoid the vehicle from entering the parking state determined based on the air chamber pressure, that is, avoiding the vehicle from unexpected parking and unexpected release of parking, thereby avoiding safety accidents and improving the safety of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 A schematic flow chart of an embodiment of a control method for an electronic parking system provided by the present invention; Figure 2 A schematic diagram of an embodiment of determining a desired parking state of an electronic parking system based on a vehicle state signal provided by the present invention; Figure 3 A schematic diagram of another embodiment of determining a desired parking state of an electronic parking system based on a vehicle state signal provided by the present invention; Figure 4 A schematic diagram of a flow chart of an embodiment of the present invention for avoiding unexpected parking; Figure 5 A schematic diagram of an embodiment of the present invention for avoiding an incompletely released parking state; Figure 6 A schematic diagram of an embodiment of the present invention for preventing unexpected parking release; Figure 7 A schematic diagram of a flow chart of an embodiment of determining the automobile safety level of an electronic handbrake button request signal provided by the present invention; Figure 8 A schematic structural diagram of an embodiment of a control device for an electronic parking system provided by the present invention; Fig. 9 A schematic structural diagram of an embodiment of a commercial vehicle provided by the present invention. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0020] It should be understood that the schematic drawings are not drawn to scale. The flowchart used in the present invention shows the operations implemented according to some embodiments of the present invention. It should be understood that the operations of the flowchart can be implemented out of order, and the steps without logical context can be reversed in order or implemented simultaneously. In addition, those skilled in the art, under the guidance of the content of the present invention, can add one or more other operations to the flowchart, and can also remove one or more operations from the flowchart. Some of the block diagrams shown in the accompanying drawings are functional entities, which do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in software form, or in one or more hardware modules or integrated circuits, or in different networks and / or processor systems and / or microcontroller systems.

[0021] Reference to an "embodiment" herein means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0022] The present invention provides a control method and device for an electronic parking system, which are described below respectively.

[0023] The embodiment of the present invention provides a control method of an electronic parking system, such as Figure 1 As shown, the control method of the electronic parking system includes: S101, obtaining the air chamber pressure of the brake air chamber and a vehicle status signal; S102, determining a parking state of the electronic parking system based on the air chamber pressure, and determining an expected parking state of the electronic parking system based on the vehicle state signal; S103: When the parking state is different from the expected parking state, a pressure adjustment signal is generated, and the air chamber pressure is adjusted based on the pressure adjustment signal to control the vehicle to maintain the expected parking state.

[0024] Compared with the prior art, the control method of the electronic parking system provided by the embodiment of the present invention can determine the parking state issued by the button switch of the electronic handbrake based on the air chamber pressure by acquiring the air chamber pressure of the brake air chamber and the vehicle status signal, and determine the expected parking state based on the vehicle status signal. When the parking state is different from the expected parking state, a pressure adjustment signal is generated to adjust the air chamber pressure, so as to control the vehicle to maintain the expected parking state and avoid the vehicle from entering the parking state determined based on the air chamber pressure, that is, avoiding the vehicle from unexpected parking and unexpected release of parking, thereby avoiding safety accidents and improving the safety of the vehicle.

[0025] It should be noted that in addition to the two safety risk states of unexpected parking and unexpected release of parking, in actual applications, there may also be a situation where the parking brake is not fully released. This situation may cause the tire to catch fire while driving.

[0026] To avoid this dangerous event, in some embodiments of the present invention, the parking state includes parking, complete parking release and incomplete parking release. Incomplete parking release means that the parking brake is not fully released.

[0027] The embodiments of the present invention can avoid unexpected parking, vehicle instability and rear-end collision by setting the parking state to include parking, and can avoid unexpected parking release and vehicle rolling down a slope and injuring people by setting the parking state to include complete parking release. Furthermore, the embodiments of the present invention take into account the parking state of incomplete parking release, and while avoiding unexpected parking and unexpected parking release, further consider the situation of tire fire caused by dragging brakes, thereby further ensuring the safety of the vehicle.

[0028] In some embodiments of the present invention, when the parking state is parking, determining the parking state of the electronic parking system based on the air chamber pressure in step S102 includes: It is determined whether the air chamber pressure is within the parking air chamber pressure range within the first preset time, and if so, the parking state is determined to be parking.

[0029] The first preset time and the parking chamber pressure range should be set according to parameters such as response sensitivity. In a specific embodiment of the present invention, the first preset time is 130ms-150ms. The parking chamber pressure range is 0bar-0.5bar.

[0030] In some embodiments of the present invention, when the parking state is not completely released, the step S102 of determining the parking state of the electronic parking system based on the air chamber pressure includes: Determine whether the air chamber pressure is less than a first pressure threshold and whether a duration during which the air chamber pressure is less than the first pressure threshold is greater than a preset duration; When the air chamber pressure is less than the first pressure threshold and the duration for which the air chamber pressure is less than the first pressure threshold is greater than a preset duration, the parking state is incompletely released.

[0031] Specifically, the first pressure threshold is any value between 5 bar and 7 bar, and the preset duration is any value between 55 s and 65 s.

[0032] In some embodiments of the present invention, when the parking state is completely released, determining the parking state of the electronic parking system based on the air chamber pressure in step S102 includes: It is determined whether the air chamber pressure is greater than a second pressure threshold, and if so, the parking state is completely released.

[0033] Specifically, the second pressure threshold is any value between 0.8 bar and 1.2 bar.

[0034] Since the parking state of not completely releasing the parking brake has an adverse effect on the driving safety of the vehicle, in other words, the parking state of not completely releasing the parking brake is an undesirable parking state. That is, the desired parking state includes parking and releasing the parking brake.

[0035] It should be understood that the desired parking state can be directly initiated by the button switch of the electronic handbrake, and can also be initiated by an external system to ensure diversity of electronic handbrake parking methods.

[0036] Specifically, the vehicle status signal includes an electronic handbrake button request signal, a transmission output shaft speed signal, a wheel speed signal, and an external system request signal; when the desired parking state is parking, such as Figure 2 As shown, determining the expected parking state of the electronic parking system based on the vehicle state signal in step S102 includes: When the electronic parking brake button request signal is a parking request signal, or the transmission output shaft vehicle speed signal is zero, the wheel speed signal is zero, and the external system request signal is a parking request signal, the desired parking state is parking.

[0037] in, Figure 2 The & in the string represents the AND logical predicate, and the || represents the OR logical predicate.

[0038] In a specific embodiment of the present invention, the vehicle state signal also includes a brake pedal signal, an accelerator pedal signal, a transmission combined brake state signal, an engine torque signal and a vehicle air pressure signal. When the desired parking state is to release the parking state, such as Figure 3 As shown, determining the expected parking state of the electronic parking system based on the vehicle state signal in step S102 includes: When the electronic parking brake button request signal is a request to release the parking state, and the brake pedal signal is a pressed signal, the desired parking state is to release the parking state; When the accelerator pedal signal is a depressed signal, the transmission combined with the brake state signal is a released signal, the engine torque signal meets the starting torque requirement and the vehicle air pressure signal meets the starting air pressure requirement, the expected parking state is to release the parking state.

[0039] In the embodiment of the present invention, when the desired parking state is set to parking and releasing parking, both can be determined based on two methods, thereby increasing the diversity of the desired parking state confirmation methods and further improving the safety of the vehicle.

[0040] In a specific embodiment of the present invention, when the parking state is parking or completely released, and the desired parking state is released, adjusting the air chamber pressure based on the pressure adjustment signal includes: Control the air inlet valve of the brake air chamber to open, and input gas into the brake air chamber until the air chamber pressure of the brake air chamber reaches the reference air pressure; When the parking state is completely released and the desired parking state is parking, the air chamber pressure is adjusted, including: The exhaust valve of the brake air chamber is controlled to open to discharge the gas in the brake air chamber until the air chamber pressure of the brake air chamber is within the parking air chamber pressure range.

[0041] The reference air pressure is any value between 7.5 bar and 9.5 bar.

[0042] In a specific embodiment of the present invention, the overall control process for avoiding undesired parking is as follows: Figure 4 As shown, specifically, when the air chamber pressure of the brake air chamber is detected to be 0bar~0.5bar within 130ms~150ms, it is determined whether the expected parking state is parking. If not, a command to open the intake valve is generated to drive the intake valve (the intake valve is a solenoid valve) of the brake air chamber to open, and to intake air into the brake air chamber to ensure that the air chamber pressure returns to the reference air pressure, thereby releasing the parking state of the air chamber and ensuring normal driving.

[0043] In a specific embodiment of the present invention, the overall control process for avoiding the incompletely released parking state is as follows: Figure 5 As shown, specifically, when it is detected that the air chamber pressure of the brake air chamber is lower than 5bar~7bar, and this state lasts for 55s~65s, it is determined whether the expected parking state is parking. If not, the intake valve of the brake air chamber is driven to open, and air is supplied to the brake air chamber to ensure that the air chamber pressure returns to the reference air pressure, release the parking state of the air chamber, and ensure normal driving.

[0044] In a specific embodiment of the present invention, the overall control process for avoiding unexpected release of parking is as follows: Figure 6As shown, specifically, when the air chamber pressure of the brake air chamber is detected to be greater than 0.8bar~1.2bar within 20ms~40ms, it is determined whether the desired parking state is to release the parking state. If not, the exhaust valve (the exhaust valve is a solenoid valve) of the brake air chamber is driven to open, and the brake air chamber is exhausted to ensure that the air chamber pressure is 0bar~0.5bar, and the parking state is maintained.

[0045] It should be noted that when the parking is unexpectedly released, the driver can be instructed to step on the brakes to avoid rolling down the slope. Figure 6 As shown, when the desired parking state is not to release the parking state, an alarm signal may be generated and sent to the instrument panel to prompt the driver, and the exhaust valve may be driven to open while the alarm signal is generated.

[0046] It should be understood that the air chamber pressure and vehicle status signals are processed by the vehicle's Electronic Control Unit (ECU), and the pressure adjustment signal is also sent by the ECU to avoid unexpected parking or unexpected release of parking due to ECU failure.

[0047] To solve the above technical problems, in some embodiments of the present invention, the automotive safety level of the ECU must reach ASIL C. The main chip and power chip in the ECU are selected to meet the ASIL C level, with a hardware single-point failure metric ≥ 97%, a latent failure metric ≥ 80%, and a random hardware failure target value < 10(-7) / h.

[0048] The embodiment of the present invention ensures that the ECU is fault-free by setting the automobile safety level and parameter requirements of the ECU, thereby further ensuring driving safety.

[0049] To further ensure the accuracy of the parking state, in some embodiments of the present invention, before adjusting the air chamber pressure based on the pressure adjustment signal, the method further includes: Verify the pressure regulation signal based on the E2E verification mechanism; Then adjust the air chamber pressure, including: When the pressure regulation signal passes the verification, the air chamber pressure is adjusted based on the pressure regulation signal.

[0050] Among them, the E2E verification mechanism can protect data exchange during operation and avoid the impact of communication link failure.

[0051] The embodiment of the present invention can ensure the accuracy of the pressure regulation signal by setting an E2E verification mechanism to verify the pressure regulation signal, thereby improving the accuracy of the air chamber pressure regulation, thereby ensuring that the vehicle can maintain the desired parking state and improving vehicle safety.

[0052] Since the electronic handbrake button request signal sent by the switch button of the electronic handbrake has different vehicle safety levels in situations such as requesting parking and requesting releasing parking, when the vehicle is set as a whole, the electronic handbrake button request signal can only have one vehicle safety level.

[0053] Therefore, in some embodiments of the present invention, Figure 7 As shown, the control method of the electronic parking system also includes: S701, obtaining a first vehicle safety level when the parking state is a request signal for an electronic handbrake button when the parking state is parked, a second vehicle safety level when the parking state is a request signal for an electronic handbrake button when the parking state is not completely released, and a third vehicle safety level when the parking state is a request signal for an electronic handbrake button when the parking state is completely released; S702: Determine a target vehicle safety level that is the highest among the first vehicle safety level, the second vehicle safety level, and the third vehicle safety level, and use the target vehicle safety level as the vehicle safety level of the electronic handbrake button request signal.

[0054] The embodiment of the present invention can ensure vehicle safety while simplifying the entire vehicle design by taking the highest vehicle safety level among the first vehicle safety level, the second vehicle safety level and the third vehicle safety level as the final vehicle safety level of the electronic handbrake button request signal.

[0055] In a specific embodiment of the present invention, the first automobile safety level is ASIL D, the second automobile safety level is ASIL C, and the third automobile safety level is ASIL C, then the target automobile safety level is ASIL D.

[0056] It should be noted that the safety level of the external parking request signal is ASIL A, the safety level of the transmission output shaft speed signal is ASIL A, the safety level of the wheel speed signal is ASIL A, the safety level of the transmission combined release brake status signal is ASIL B, and the safety level of the engine actual torque signal is ASIL A.

[0057] In summary, the control method of the electronic parking system proposed in the embodiment of the present invention derives clear EPB safety goals based on the functional safety process and then decomposes the safety control method, and prevents unexpected parking braking during driving, prevents insufficient release of the parking brake during driving, and prevents unexpected parking release from forward development, effectively reduces the safety risks of the vehicle caused by abnormal functions of EPB-related electronic and electrical systems, and improves driving safety.

[0058] In addition, a safety monitoring mechanism is designed, namely: the air chamber pressure is adjusted based on the generated pressure regulation signal to ensure that even if unexpected parking braking occurs while driving, the parking brake is not fully released while driving, or the parking is released unexpectedly, the EPB system will quickly enter a safe state to ensure that no personal or property damage occurs.

[0059] In order to better implement the control method of the electronic parking system in the embodiment of the present invention, based on the control method of the electronic parking system, the embodiment of the present invention also provides a control device of the electronic parking system, such as Figure 8 As shown, the control device 800 of the electronic parking system includes: A data acquisition unit 801 is used to acquire the air chamber pressure of the brake air chamber and a vehicle status signal; a parking state determining unit 802, configured to determine the parking state of the electronic parking system based on the air chamber pressure, and to determine the desired parking state of the electronic parking system based on the vehicle state signal; The parking state control unit 803 is used to generate a pressure adjustment signal when the parking state is different from the expected parking state, and adjust the air chamber pressure based on the pressure adjustment signal to control the vehicle to maintain the expected parking state.

[0060] It should be noted that the control device 800 of the electronic parking system provided in the above embodiment can implement the technical solution described in the above electronic parking system control method embodiment. The specific implementation principles or specific implementation details of the above modules or units can refer to the corresponding contents in the above electronic parking system control method embodiment, which will not be described one by one here.

[0061] like Fig. 9 As shown, the present invention also provides a commercial vehicle 900. The commercial vehicle 900 includes a processor 901, a memory 902 and a display 903. Fig. 9 Only some of the components of the commercial vehicle 900 are shown, but it should be understood that implementation of all of the components shown is not required, and more or fewer components may be implemented instead.

[0062] In some embodiments, the processor 901 is an electronic control unit (ECU) in the commercial vehicle 900 , which is used to run program codes or process data stored in the memory 902 , such as the control method of the electronic parking system in the present invention.

[0063] In some embodiments, the memory 902 may be an internal storage unit of the commercial vehicle 900 , such as a hard disk or a memory of the commercial vehicle 900 .

[0064] Furthermore, the memory 902 may include both an internal storage unit and an external storage device of the commercial vehicle 900. The memory 902 is used to store application software installed in the commercial vehicle 900 and various data.

[0065] In some embodiments, the display 903 may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, an OLED (Organic Light-Emitting Diode) touch device, etc. The display 903 is used to display information of the commercial vehicle 900 and to display a visual user interface. The components 901-903 of the commercial vehicle 900 communicate with each other via a system bus.

[0066] In some embodiments of the present invention, when the processor 901 executes the control program of the electronic parking system in the memory 902, the following steps may be implemented: Acquire the air chamber pressure of the brake air chamber and the vehicle status signal; determining a parking state of the electronic parking system based on the air chamber pressure, and determining a desired parking state of the electronic parking system based on the vehicle state signal; When the parking state is different from the desired parking state, a pressure adjustment signal is generated, and the air chamber pressure is adjusted based on the pressure adjustment signal to control the vehicle to maintain the desired parking state.

[0067] It should be understood that: when the processor 901 executes the control program of the electronic parking system in the memory 902, in addition to the above functions, other functions can also be implemented. For details, please refer to the description of the corresponding method embodiment above.

[0068] Accordingly, an embodiment of the present invention further provides a computer-readable storage medium, which is used to store computer-readable programs or instructions. When the program or instructions are executed by a processor, the steps or functions in the control method of the electronic parking system provided by the above-mentioned method embodiments can be implemented.

[0069] Those skilled in the art will appreciate that all or part of the processes of the above-mentioned embodiments can be implemented by instructing related hardware (such as a processor, a controller, etc.) through a computer program, and the computer program can be stored in a computer-readable storage medium, wherein the computer-readable storage medium is a disk, an optical disk, a read-only storage memory, or a random access memory, etc.

[0070] The control method and device of an electronic parking system provided by the present invention are introduced in detail above. Specific examples are used in this article to illustrate the principle and implementation mode of the present invention. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation mode and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A control method for an electronic parking system, characterized in that: include: Acquire the air chamber pressure of the brake air chamber and the vehicle status signal; determining a parking state of the electronic parking system based on the air chamber pressure, and determining a desired parking state of the electronic parking system based on the vehicle state signal; When the parking state is different from the desired parking state, a pressure adjustment signal is generated, and the air chamber pressure is adjusted based on the pressure adjustment signal to control the vehicle to maintain the desired parking state.

2. The control method of the electronic parking system according to claim 1, characterized in that: The parking state includes parking; then determining the parking state of the electronic parking system based on the air chamber pressure includes: It is determined that the air chamber pressure is within the parking air chamber pressure range within the first preset time, and if so, the parking state is determined to be parking.

3. The control method of the electronic parking system according to claim 2, characterized in that: The parking state also includes incomplete release of parking; then determining the parking state of the electronic parking system based on the air chamber pressure includes: Determining whether the air chamber pressure is less than a first pressure threshold and whether a duration for which the air chamber pressure is less than the first pressure threshold is greater than a preset duration; When the air chamber pressure is less than a first pressure threshold and a duration for which the air chamber pressure is less than the first pressure threshold is greater than a preset duration, the parking state is incompletely released.

4. The control method of the electronic parking system according to claim 3, characterized in that: The parking state also includes completely releasing the parking state; then determining the parking state of the electronic parking system based on the air chamber pressure includes: It is determined whether the air chamber pressure is greater than a second pressure threshold, and if so, the parking state is completely released.

5. The control method of the electronic parking system according to claim 4, characterized in that: The desired parking state includes parking, and the vehicle state signal includes an electronic parking brake button request signal, a transmission output shaft vehicle speed signal, a wheel speed signal, and an external system request signal; Then, determining the expected parking state of the electronic parking system based on the vehicle state signal includes: When the electronic parking brake button request signal is a parking request signal, or the transmission output shaft vehicle speed signal is zero, the wheel speed signal is zero and the external system request signal is a parking request signal, the desired parking state is parking.

6. The control method of the electronic parking system according to claim 5, characterized in that: The desired parking state also includes releasing parking, and the vehicle state signal also includes a brake pedal signal, an accelerator pedal signal, a transmission combined brake state signal, an engine torque signal, and a vehicle air pressure signal; Then, determining the expected parking state of the electronic parking system based on the vehicle state signal includes: When the electronic parking brake button request signal is a request to release parking, and the brake pedal signal is a pressed signal, the desired parking state is to release parking; When the accelerator pedal signal is a depressed signal, the transmission combined with the brake state signal is a released signal, the engine torque signal meets the starting torque requirement, and the vehicle air pressure signal meets the starting air pressure requirement, the expected parking state is released parking.

7. The control method of the electronic parking system according to claim 1, characterized in that: When the parking state is parking or fully released, and the expected parking state is released, adjusting the air chamber pressure based on the pressure adjustment signal includes: Controlling the air inlet valve of the brake air chamber to open, and inputting gas into the brake air chamber until the air chamber pressure of the brake air chamber reaches the reference air pressure; When the parking state is completely released from parking and the desired parking state is parking, the step of adjusting the air chamber pressure includes: The exhaust valve of the brake air chamber is controlled to open to exhaust the gas in the brake air chamber until the air chamber pressure of the brake air chamber is within the parking air chamber pressure range.

8. The control method of the electronic parking system according to claim 1, characterized in that: Before adjusting the air chamber pressure based on the pressure adjustment signal, the method further includes: Verifying the pressure regulation signal based on an E2E verification mechanism; Then the step of adjusting the air chamber pressure comprises: When the pressure regulating signal passes the verification, the air chamber pressure is adjusted based on the pressure regulating signal.

9. The control method of the electronic parking system according to claim 6, characterized in that: The method further comprises: Acquire a first vehicle safety level when the parking state is a request signal for an electronic handbrake button when the parking state is parked, a second vehicle safety level when the parking state is a request signal for an electronic handbrake button when the parking state is not completely released, and a third vehicle safety level when the parking state is a request signal for an electronic handbrake button when the parking state is completely released; A target vehicle safety level that is the highest among the first vehicle safety level, the second vehicle safety level, and the third vehicle safety level is determined, and the target vehicle safety level is used as the vehicle safety level of the electronic handbrake button request signal.

10. A control device for an electronic parking system, characterized in that: include: A data acquisition unit, used to acquire the air chamber pressure of the brake air chamber and a vehicle status signal; a parking state determining unit, configured to determine a parking state of the electronic parking system based on the air chamber pressure, and to determine a desired parking state of the electronic parking system based on the vehicle state signal; The parking state control unit is used to generate a pressure adjustment signal when the parking state is different from the expected parking state, and adjust the air chamber pressure based on the pressure adjustment signal to control the vehicle to maintain the expected parking state.

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