A control method and device for an electronic parking system

Abstract

This invention provides a control method and apparatus for an electronic parking brake system, belonging to the field of parking brake technology. The method includes: acquiring the chamber pressure of the brake chamber and a vehicle status signal; determining the parking state of the electronic parking brake system based on the chamber pressure, and determining the desired parking state of the electronic parking brake system based on the vehicle status signal; when the parking state differs from the desired parking state, generating a pressure adjustment signal, and adjusting the chamber pressure based on the pressure adjustment signal to control the vehicle to maintain the desired parking state. This invention controls the vehicle to maintain the desired parking state when the parking state differs from the desired parking state, avoiding undesired parking and undesired release of the vehicle, thereby preventing safety accidents and improving vehicle safety.

Description

Technical Field

[0001] This invention relates to the field of parking brake technology, and more specifically to a control method and device for an electronic parking system. Background Technology

[0002] Traditional commercial vehicle handbrakes are primarily implemented using pneumatic structures, which are simple and reliable. However, with the increasing demands for intelligent and electrified technologies, Electronic Park Brake (EPB) systems are gradually becoming a key application in commercial vehicles. Compared to traditional handbrakes, the operation involves pressing and releasing a push-button switch (HCU) to send a command to the EPB's ECU. The EPB's ECU then controls the opening and closing of solenoid valves to vent or intake air from the braking system, thereby achieving parking braking or releasing the vehicle.

[0003] The EPB collects digital signals from the HCU, which are then calculated by the ECU to control the actuators to achieve parking. If the HCU output signal is incorrect, it can easily lead to unexpected parking or unexpected release of the parking brake, thereby causing a safety accident.

[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 the parking brake when the HCU output signal is erroneous, thereby ensuring vehicle driving safety. 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 parking brake 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-mentioned technical problems, the present invention provides a control method for an electronic parking system, comprising:

[0007] Acquire the air chamber pressure of the brake chamber and vehicle status signals;

[0008] The parking status of the electronic parking system is determined based on the air chamber pressure, and the desired parking status of the electronic parking system is determined based on the vehicle status signal.

[0009] When the parking state is different from the desired parking state, a pressure regulation signal is generated, and the air chamber pressure is adjusted based on the pressure regulation signal to control the vehicle to maintain the desired parking state.

[0010] In one possible implementation, the parking state includes parking; then determining the parking state of the electronic parking system based on the air chamber pressure includes:

[0011] Determine whether the air chamber pressure is within the parking air chamber pressure range within a first preset time period. If so, determine that the parking state is parking.

[0012] In one possible implementation, the parking state further includes not fully releasing the parking brake; then determining the parking state of the electronic parking system based on the air chamber pressure includes:

[0013] Determine whether the air chamber pressure is less than a first pressure threshold and whether the duration for which the air chamber pressure is less than the first pressure threshold is greater than a preset duration;

[0014] When the air chamber pressure is less than a first pressure threshold and the duration of the air chamber pressure being less than the first pressure threshold is greater than a preset duration, the parking state is that the parking is not completely released.

[0015] In one possible implementation, the parking state further includes completely releasing the parking brake; then determining the parking state of the electronic parking system based on the air chamber pressure includes:

[0016] Determine whether the air chamber pressure is greater than the second pressure threshold. If so, the parking state is fully released.

[0017] In one possible implementation, the desired parking state includes parking, and the vehicle status signals include an electronic parking brake button request signal, a transmission output shaft vehicle speed signal, wheel speed signals, and an external system request signal.

[0018] Determining the desired parking state of the electronic parking system based on the vehicle status signal includes:

[0019] When the electronic parking brake button request signal is a parking request signal, or when 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.

[0020] In one possible implementation, the desired parking state further includes releasing the parking brake, and the vehicle status signals further include brake pedal signal, accelerator pedal signal, transmission engagement braking status signal, engine torque signal, and vehicle air pressure signal.

[0021] Determining the desired parking state of the electronic parking system based on the vehicle status signal includes:

[0022] When the electronic parking brake button request signal is a request to release the parking brake, and the brake pedal signal is a depressed signal, the desired parking state is to release the parking brake.

[0023] When the accelerator pedal signal is depressed, the transmission engagement braking state signal is released, the engine torque signal meets the starting torque requirement, and the vehicle air pressure signal meets the starting air pressure requirement, the desired parking state is to release the parking brake.

[0024] In one possible implementation, when the parking state is parked or fully released, and the desired parking state is released, adjusting the air chamber pressure based on the pressure adjustment signal includes:

[0025] The air inlet valve of the brake chamber is opened to input gas into the brake chamber until the chamber pressure of the brake chamber is the reference pressure.

[0026] When the parking state is fully released and the desired parking state is parking, adjusting the air chamber pressure includes:

[0027] The exhaust valve of the brake chamber is opened to release the gas in the brake chamber until the pressure in the brake chamber is within the parking chamber pressure range.

[0028] In one possible implementation, before adjusting the chamber pressure based on the pressure regulation signal, the method further includes:

[0029] The pressure regulation signal is verified based on the E2E verification mechanism;

[0030] The adjustment of the air chamber pressure includes:

[0031] Once the pressure regulation signal passes the verification, the pressure in the air chamber is adjusted based on the pressure regulation signal.

[0032] In one possible implementation, the method further includes:

[0033] The vehicle safety level is obtained as follows: a first vehicle safety level when the parking state is an electronic parking brake button request signal, a second vehicle safety level when the parking state is an electronic parking brake button request signal that is not fully released, and a third vehicle safety level when the parking state is an electronic parking brake button request signal that is fully released.

[0034] The highest target vehicle safety level 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 parking brake button request signal.

[0035] On the other hand, the present invention also provides a control device for an electronic parking system, comprising:

[0036] The data acquisition unit is used to acquire the air chamber pressure of the brake chamber and vehicle status signals;

[0037] A parking status determination unit is used to determine the parking status of the electronic parking system based on the air chamber pressure, and to determine the desired parking status of the electronic parking system based on the vehicle status signal.

[0038] A parking status control unit is used to generate a pressure regulation signal when the parking status is different from the desired parking status, and to adjust the air chamber pressure based on the pressure regulation signal to control the vehicle to maintain the desired parking status.

[0039] The beneficial effects of this invention are as follows: The control method of the electronic parking system provided by this invention can determine the parking state issued by the button switch of the electronic handbrake based on the air chamber pressure and the vehicle status signal by acquiring the air chamber pressure of the brake chamber. It can also determine the desired parking state based on the vehicle status signal. When the parking state is different from the desired parking state, a pressure adjustment signal is generated to adjust the air chamber pressure, thereby controlling the vehicle to maintain the desired parking state and preventing the vehicle from entering the parking state determined based on the air chamber pressure. In other words, it avoids undesirable parking and undesirable release of the vehicle, thereby avoiding safety accidents and improving vehicle safety. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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 effort.

[0041] Figure 1 A schematic flowchart of an embodiment of the control method for the electronic parking system provided by the present invention;

[0042] Figure 2 A schematic diagram of an embodiment of the present invention for determining the desired parking state of an electronic parking system based on vehicle status signals;

[0043] Figure 3 This is a schematic diagram of another embodiment of the electronic parking system for determining the desired parking state based on vehicle status signals provided by the present invention;

[0044] Figure 4 A schematic diagram of an embodiment of the present invention for avoiding undesirable parking;

[0045] Figure 5 A schematic diagram of an embodiment of the present invention for avoiding a parking state that is not fully released;

[0046] Figure 6 A schematic diagram illustrating an embodiment of the present invention for avoiding unintended release of parking space;

[0047] Figure 7 A schematic flowchart illustrating an embodiment of the present invention for determining the vehicle safety level of an electronic parking brake button request signal;

[0048] Figure 8 A schematic diagram of an embodiment of the control device for the electronic parking system provided by the present invention;

[0049] Figure 9 A schematic diagram of an embodiment of a commercial vehicle provided by the present invention. Detailed Implementation

[0050] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0051] It should be understood that the illustrative drawings are not drawn to scale. The flowcharts used in this invention illustrate operations implemented according to some embodiments of the invention. It should be understood that the operations in the flowcharts may be implemented out of order, and steps without logical contextual relationships may be reversed or performed simultaneously. Furthermore, those skilled in the art, guided by the content of this invention, may add one or more other operations to the flowcharts, or remove one or more operations from the flowcharts. Some block diagrams shown in the drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities may be implemented in software, in one or more hardware modules or integrated circuits, or in different network and / or processor systems and / or microcontroller systems.

[0052] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0053] This invention provides a control method and apparatus for an electronic parking system, which will be described below.

[0054] This invention provides a control method for an electronic parking system, such as... Figure 1As shown, the control method of the electronic parking system includes:

[0055] S101. Obtain the air chamber pressure of the brake chamber and the vehicle status signal;

[0056] S102. Determine the parking status of the electronic parking system based on the air chamber pressure, and determine the desired parking status of the electronic parking system based on the vehicle status signal.

[0057] S103. When the parking state is different from the desired parking state, a pressure regulation signal is generated, and the air chamber pressure is adjusted based on the pressure regulation signal to control the vehicle to maintain the desired parking state.

[0058] Compared with the prior art, the control method of the electronic parking system provided in this embodiment of the invention can determine the parking state issued by the button switch of the electronic handbrake based on the air chamber pressure and the vehicle status signal by acquiring the air chamber pressure of the brake chamber and the vehicle status signal. It can also determine the desired parking state based on the air chamber pressure and the vehicle status signal. When the parking state is different from the desired parking state, a pressure adjustment signal is generated to adjust the air chamber pressure and control the vehicle to maintain the desired parking state. This prevents the vehicle from entering the parking state determined based on the air chamber pressure, that is, it avoids undesired parking and undesired release of the vehicle, thereby avoiding safety accidents and improving vehicle safety.

[0059] It should be noted that, in addition to the two safety risks of unintended parking and unintended release of the parking brake, in practical applications, there is also the situation where the parking brake is not fully released. This situation can cause the dragging tire to catch fire while driving.

[0060] To avoid this dangerous incident, in some embodiments of the present invention, the parking state includes parking, fully released parking, and partially released parking. Incompletely released parking means that the parking brake is not fully released.

[0061] This invention, by setting a parking state including "parked," can prevent unintended parking, vehicle instability, and rear-end collisions. Setting a parking state including "fully released" can prevent unintended release, thus preventing the vehicle from rolling backward and injuring occupants. Furthermore, this invention also considers the parking state of not fully releasing the parking brake, thus addressing the possibility of a tire catching fire while dragging the brakes, further ensuring vehicle safety.

[0062] In some embodiments of the present invention, when the parking state is "parked", step S102, which determines the parking state of the electronic parking system based on the air chamber pressure, includes:

[0063] Determine whether the air chamber pressure is within the parking air chamber pressure range within the first preset time. If so, determine the parking state as parking.

[0064] 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 to 150ms. The parking chamber pressure range is 0bar to 0.5bar.

[0065] In some embodiments of the present invention, when the parking status is that the parking is not fully released, step S102, which involves determining the parking status of the electronic parking system based on the air chamber pressure, includes:

[0066] Determine whether the air chamber pressure is less than a first pressure threshold and whether the duration of the air chamber pressure being less than the first pressure threshold is greater than a preset duration;

[0067] When the air chamber pressure is less than the first pressure threshold and the duration of the air chamber pressure being less than the first pressure threshold is greater than the preset duration, the parking status is that the parking is not completely released.

[0068] 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.

[0069] In some embodiments of the present invention, when the parking state is fully released, step S102, which determines the parking state of the electronic parking system based on the air chamber pressure, includes:

[0070] Determine if the air chamber pressure is greater than the second pressure threshold. If so, the parking status is fully released.

[0071] Specifically, the second pressure threshold is any value between 0.8 bar and 1.2 bar.

[0072] Because not fully releasing the parking brake has an adverse impact on vehicle driving safety, in other words, not fully releasing the parking brake is an undesirable parking state. That is, the desired parking state includes both parking and releasing the parking brake.

[0073] It should be understood that the parking state should be initiated either directly by the electronic parking brake button switch or by an external system to ensure the versatility of the electronic parking brake parking method.

[0074] Specifically, vehicle status signals include electronic parking brake button request signals, transmission output shaft vehicle speed signals, wheel speed signals, and external system request signals; when the desired parking state is parking, such as Figure 2 As shown, step S102, determining the desired parking state of the electronic parking system based on the vehicle status signal, includes:

[0075] When the electronic parking brake button request signal is a parking request signal, or when 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.

[0076] in, Figure 2 In this context, & represents the AND logical operator, and || represents the OR logical operator.

[0077] In a specific embodiment of the present invention, the vehicle status signal further includes a brake pedal signal, an accelerator pedal signal, a transmission engagement braking status signal, an engine torque signal, and a vehicle air pressure signal. When the desired parking state is parking released, such as... Figure 3 As shown, step S102, determining the desired parking state of the electronic parking system based on the vehicle status signal, includes:

[0078] When the electronic parking brake button request signal is a request to release the parking brake, and the brake pedal signal is a depressed signal, the desired parking state is to release the parking brake.

[0079] When the accelerator pedal signal is depressed, the transmission engagement braking signal is released, the engine torque signal meets the starting torque requirement, and the vehicle air pressure signal meets the starting air pressure requirement, the desired parking state is to release the parking brake.

[0080] In this embodiment of the invention, the desired parking state can be determined based on two methods when setting it to either parked or released from parking, which increases the diversity of methods for confirming the desired parking state and further improves vehicle safety.

[0081] In a specific embodiment of the present invention, when the parking state is parked or fully released, and the desired parking state is released, the air chamber pressure is adjusted based on the pressure adjustment signal, including:

[0082] The air intake valve of the brake chamber is opened to input gas into the brake chamber until the air pressure in the brake chamber reaches the reference air pressure.

[0083] When the parking status is fully released and the desired parking status is parking, adjust the air chamber pressure, including:

[0084] The exhaust valve of the brake chamber is opened to release the gas in the brake chamber until the pressure in the brake chamber is within the range of the parking chamber pressure.

[0085] The reference pressure is any value between 7.5 bar and 9.5 bar.

[0086] In a specific embodiment of the present invention, the overall control process for avoiding undesirable parking is as follows: Figure 4As shown, specifically, when the brake chamber pressure is detected to be 0 bar to 0.5 bar within 130ms to 150ms, it is determined whether the desired parking state is parking. If not, a command to open the intake valve is generated to drive the intake valve of the brake chamber (the intake valve is a solenoid valve) to open, allowing air to enter the brake chamber, ensuring that the chamber pressure returns to the reference pressure, releasing the parking state of the chamber, and ensuring normal driving.

[0087] In a specific embodiment of the present invention, the overall control process to avoid the occurrence of an incompletely released parking state is as follows: Figure 5 As shown, specifically, when the brake chamber pressure is detected to be lower than 5 bar to 7 bar and this state lasts for 55 to 65 seconds, it is determined whether the desired parking state is parking. If not, the intake valve of the brake chamber is opened to allow air to enter the brake chamber, ensuring that the chamber pressure returns to the reference pressure, releasing the parking state of the chamber, and ensuring normal driving.

[0088] In a specific embodiment of the present invention, the overall control process for avoiding unintended release of parking is as follows: Figure 6 As shown, specifically, when the air chamber pressure of the brake chamber is detected to be greater than 0.8 bar to 1.2 bar within 20 ms to 40 ms, it is determined whether the desired parking state is to release the parking. If not, the exhaust valve of the brake chamber (the exhaust valve is a solenoid valve) is opened to exhaust the brake chamber and ensure that the air chamber pressure is 0 bar to 0.5 bar, thus maintaining the parking state.

[0089] It should be noted that when the parking brake is unexpectedly released, instructing the driver to apply the brakes will prevent the vehicle from rolling backwards. Therefore, if... Figure 6 As shown, when the desired parking state is not the parking release state, an alarm signal can be generated and sent to the instrument panel to alert the driver. At the same time as generating the alarm signal, the exhaust valve is activated.

[0090] 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 regulation signal is also issued by the ECU. This is to prevent unexpected parking or unexpected release of the parking brake when the ECU malfunctions.

[0091] To address the aforementioned technical problems, in some embodiments of the present invention, the vehicle safety level of the ECU must reach ASIL C. The main chip and power supply chip in the ECU are selected from products that meet ASIL C standards, with a single-point hardware failure rate ≥97%, a latent failure rate ≥80%, and a random hardware failure target value <10(-7) / h.

[0092] This invention ensures that the ECU is fault-free by setting the vehicle safety level and parameter requirements of the ECU, thereby further ensuring driving safety.

[0093] To further ensure the accuracy of the parking status, in some embodiments of the present invention, before adjusting the air chamber pressure based on the pressure regulation signal, the following steps are also included:

[0094] The pressure regulation signal is verified based on the E2E verification mechanism;

[0095] The pressure in the air chamber is adjusted, including:

[0096] Once the pressure regulation signal passes verification, the pressure in the air chamber is adjusted based on the pressure regulation signal.

[0097] Among them, the E2E verification mechanism can protect data exchange during operation from the impact of communication link failures.

[0098] This invention implements an E2E verification mechanism to verify the pressure regulation signal, thereby ensuring the accuracy of the pressure regulation signal and improving the accuracy of air chamber pressure regulation. This ensures that the vehicle can maintain the desired parking state and improves vehicle safety.

[0099] Because the electronic parking brake button request signal emitted by the electronic parking brake switch button does not have the same vehicle safety level when requesting to park or release the parking brake, but when the vehicle is configured as a whole, the electronic parking brake button request signal can only have one vehicle safety level.

[0100] Therefore, in some embodiments of the present invention, such as Figure 7 As shown, the control method of the electronic parking system also includes:

[0101] S701. Obtain a first vehicle safety level when the parking state is parking, a second vehicle safety level when the parking state is not fully released, and a third vehicle safety level when the parking state is fully released.

[0102] S702. Determine the highest target vehicle safety level 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 for the electronic parking brake button request signal.

[0103] This invention uses the highest vehicle safety level among the first, second, and third vehicle safety levels as the final vehicle safety level for the electronic parking brake button request signal, which simplifies the overall vehicle design while ensuring vehicle safety.

[0104] In a specific embodiment of the present invention, if the first vehicle safety level is ASIL D, the second vehicle safety level is ASIL C, and the third vehicle safety level is ASIL C, then the target vehicle safety level is ASIL D.

[0105] 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 vehicle speed signal is ASIL A, the safety level of the wheel speed signal is ASIL A, the safety level of the transmission engagement and release braking status signal is ASIL B, and the safety level of the engine actual torque signal is ASIL A.

[0106] In summary, the control method for the electronic parking system proposed in this invention decomposes the safety control method based on the functional safety process to extract clear EPB safety objectives. It prevents unintended parking braking, insufficient release of the parking brake, and unintended release of the parking brake during driving from a forward-developed perspective, effectively reducing the safety risks of vehicle caused by abnormal functions of EPB-related electronic and electrical systems and improving driving safety.

[0107] Furthermore, a safety monitoring mechanism is designed, namely: adjusting the air chamber pressure based on the generated pressure regulation signal to ensure that even if unexpected parking braking occurs during driving, the parking brake is not fully released during driving, or the parking brake is unexpectedly released, the EPB system will quickly enter a safe state to ensure that no personal injury or property damage occurs.

[0108] To better implement the control method of the electronic parking system in the embodiments of the present invention, based on the control method of the electronic parking system, the embodiments of the present invention also provide a control device for the electronic parking system, such as... Figure 8 As shown, the control device 800 of the electronic parking system includes:

[0109] The data acquisition unit 801 is used to acquire the air chamber pressure of the brake chamber and the vehicle status signal;

[0110] The parking status determination unit 802 is used to determine the parking status of the electronic parking system based on the air chamber pressure, and to determine the desired parking status of the electronic parking system based on the vehicle status signal.

[0111] The parking status control unit 803 is used to generate a pressure regulation signal when the parking status is different from the desired parking status, and to adjust the air chamber pressure based on the pressure regulation signal to control the vehicle to maintain the desired parking status.

[0112] It should be noted that the control device 800 of the electronic parking system provided in the above embodiments can realize the technical solutions described in the above electronic parking system control method embodiments. The specific implementation principles or implementation details of each module or unit can be found in the corresponding content of the above electronic parking system control method embodiments, which will not be elaborated here.

[0113] like Figure 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. Figure 9 Only some of the components of the Commercial Vehicle 900 are shown, but it should be understood that implementation of all the components shown is not required, and more or fewer components may be implemented instead.

[0114] In some embodiments, processor 901 is an electronic control unit (ECU) in a commercial vehicle 900, used to run program code stored in memory 902 or process data, such as the control method of the electronic parking system in this invention.

[0115] In some embodiments, memory 902 may be an internal storage unit of commercial vehicle 900, such as hard disk or memory of commercial vehicle 900.

[0116] Furthermore, the memory 902 may include both internal storage units of the commercial vehicle 900 and external storage devices. The memory 902 is used to store application software and various types of data installed on the commercial vehicle 900.

[0117] In some embodiments, display 903 may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, or an OLED (Organic Light-Emitting Diode) touchscreen. Display 903 is used to display information about the commercial vehicle 900 and to display a visual user interface. Components 901-903 of the commercial vehicle 900 communicate with each other via a system bus.

[0118] In some embodiments of the present invention, when the processor 901 executes the control program for the electronic parking system in the memory 902, the following steps can be implemented:

[0119] Acquire the air chamber pressure of the brake chamber and vehicle status signals;

[0120] The parking status of the electronic parking system is determined based on the air chamber pressure, and the desired parking status of the electronic parking system is determined based on the vehicle status signal.

[0121] When the parking state is different from the desired parking state, a pressure regulation signal is generated, and the air chamber pressure is adjusted based on the pressure regulation signal to control the vehicle to maintain the desired parking state.

[0122] 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 functions mentioned above, it can also perform other functions, as can be found in the description of the corresponding method embodiments above.

[0123] Accordingly, embodiments of the present invention also provide a computer-readable storage medium for storing computer-readable programs or instructions. When the programs or instructions are executed by a processor, they can implement the steps or functions of the control methods of the electronic parking system provided in the above-described method embodiments.

[0124] Those skilled in the art will understand that all or part of the processes of the methods described in the above embodiments can be implemented by a computer program instructing related hardware (such as a processor, controller, etc.), and the computer program can be stored in a computer-readable storage medium. The computer-readable storage medium may be a disk, optical disk, read-only memory, or random access memory, etc.

[0125] The control method and device for an electronic parking system provided by the present invention have been described in detail above. Specific examples have been used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of ​​the present invention. Therefore, the content of this specification should not be construed as a limitation of 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 chamber and vehicle status signals; The parking state of the electronic parking system is determined based on the air chamber pressure, and the desired parking state of the electronic parking system is determined based on the vehicle status signals; the vehicle status signals include electronic handbrake button request signal, transmission output shaft vehicle speed signal, wheel speed signal, external system request signal, brake pedal signal, accelerator pedal signal, transmission engagement braking state signal, engine torque signal, and vehicle air pressure signal; When the parking state is different from the desired parking state, a pressure regulation signal is generated, and the air chamber pressure is adjusted based on the pressure regulation signal to control the vehicle to maintain the desired parking state. When the parking state is parking or fully released, and the desired parking state is released, adjusting the air chamber pressure based on the pressure regulation signal includes: The air inlet valve of the brake chamber is opened to input gas into the brake chamber until the chamber pressure of the brake chamber is the reference pressure. When the parking state is fully released and the desired parking state is parking, adjusting the air chamber pressure includes: The exhaust valve of the brake chamber is opened to release the gas in the brake chamber until the pressure in the brake chamber is within the parking chamber pressure range.

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

3. The control method for the electronic parking system according to claim 2, characterized in that, The parking status also includes not fully releasing the parking brake; therefore, determining the parking status 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 the 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 the duration of the air chamber pressure being less than the first pressure threshold is greater than a preset duration, the parking state is that the parking is not completely released.

4. The control method for the electronic parking system according to claim 3, characterized in that, The parking state also includes fully releasing the parking brake; therefore, determining the parking state of the electronic parking system based on the air chamber pressure includes: Determine whether the air chamber pressure is greater than the second pressure threshold. If so, the parking state is fully released.

5. The control method for the electronic parking system according to claim 4, characterized in that, The desired parking status includes parking; Determining the desired parking state of the electronic parking system based on the vehicle status signal includes: When the electronic parking brake button request signal is a parking request signal, or when 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 for the electronic parking system according to claim 5, characterized in that, The desired parking state also includes releasing the parking position; Determining the desired parking state of the electronic parking system based on the vehicle status signal includes: When the electronic parking brake button request signal is a request to release the parking brake, and the brake pedal signal is a depressed signal, the desired parking state is to release the parking brake. When the accelerator pedal signal is depressed, the transmission engagement braking state signal is released, the engine torque signal meets the starting torque requirement, and the vehicle air pressure signal meets the starting air pressure requirement, the desired parking state is to release the parking brake.

7. The control method for the electronic parking system according to claim 1, characterized in that, Before adjusting the chamber pressure based on the pressure regulation signal, the method further includes: The pressure regulation signal is verified based on the E2E verification mechanism; The adjustment of the air chamber pressure includes: Once the pressure regulation signal passes the verification, the pressure in the air chamber is adjusted based on the pressure regulation signal.

8. The control method for the electronic parking system according to claim 6, characterized in that, The method further includes: The vehicle safety level is obtained as follows: a first vehicle safety level when the parking state is an electronic parking brake button request signal, a second vehicle safety level when the parking state is an electronic parking brake button request signal that is not fully released, and a third vehicle safety level when the parking state is an electronic parking brake button request signal that is fully released. The highest target vehicle safety level 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 parking brake button request signal.

9. A control device for an electronic parking system, characterized in that, include: The data acquisition unit is used to acquire the air chamber pressure of the brake chamber and vehicle status signals; The parking status determination unit is used to determine the parking status of the electronic parking system based on the air chamber pressure, and to determine the desired parking status of the electronic parking system based on the vehicle status signals; the vehicle status signals include electronic handbrake button request signal, transmission output shaft vehicle speed signal, wheel speed signal, external system request signal, brake pedal signal, accelerator pedal signal, transmission engagement braking status signal, engine torque signal, and vehicle air pressure signal; A parking status control unit is used to generate a pressure regulation signal when the parking status is different from the desired parking status, and to adjust the air chamber pressure based on the pressure regulation signal to control the vehicle to maintain the desired parking status. When the parking state is parking or fully released, and the desired parking state is released, adjusting the air chamber pressure based on the pressure regulation signal includes: The air inlet valve of the brake chamber is opened to input gas into the brake chamber until the chamber pressure of the brake chamber is the reference pressure. When the parking state is fully released and the desired parking state is parking, adjusting the air chamber pressure includes: The exhaust valve of the brake chamber is opened to release the gas in the brake chamber until the pressure in the brake chamber is within the parking chamber pressure range.

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