Method and system for brake boosting of a vehicle

Abstract

The present invention relates to a method and system for brake boosting of a vehicle. The method comprises: determining whether a brake booster of the vehicle is in a failed state; in response to determining that the brake booster is in a normal state, instructing the brake booster to provide brake boosting during the braking process of the vehicle; and in response to determining that the brake booster is in a failed state, providing additional brake force boosting during the braking process of the vehicle to achieve the required deceleration. The embodiments of the present invention can improve the braking performance of the vehicle, provide accurate brake boosting compensation in time when the brake booster fails, and ensure driving safety.

Description

Technical Field

[0001] The invention relates to a method and a system for brake boosting of a vehicle. Background Art

[0002] At present, electromechanical servo booster mechanisms for vehicle braking have been applied, and many new energy vehicles have been equipped with such brake boosters. For example, Bosch has designed an intelligent brake booster product iBooster, which can integrate various sensors and controllers, use the internal sensors of the mechanism to respond to the driver's braking action, and convert the driver's braking action into a signal, and transmit the converted signal to the motor control unit in the brake pump. The motor control unit calculates the torque requirement that the motor should generate, and the secondary gear unit device converts the torque into the servo braking force of the booster valve body, and finally drives the amplification mechanism to finally push the brake pump to start working, realizing electronic control braking. Compared with traditional brakes, this electromechanical servo booster mechanism cancels the design of the vacuum pump and replaces it with various types of sensors and controllers, making the entire mechanism smaller and lighter, saving a lot of space and weight when installing the vehicle, and its response speed is faster and can accurately control the brake boost.

[0003] However, when the brake booster fails, the brake boost cannot be provided in time, and the driver will feel that the brake pedal is difficult to depress and needs to be pressed hard to generate the master cylinder pressure (pMC) of the brake pump. For example, when the brake booster fails, the driver's brake request pressure is calculated by measuring the master cylinder pressure (pMC). Only when a sufficient amount of master cylinder pressure is measured in the brake pump, the hydraulic booster failure compensation system (HBC) will start to apply pressure to the driver; it may be too late for the driver to apply the required pressure on the brake pedal to achieve the required deceleration. In addition, when the brake booster fails, the driver will find it difficult to apply the brake pedal to the minimum pressure. Moreover, it is difficult to calculate the target pressure without measuring the pressure applied by the driver. Summary of the invention

[0004] The present invention aims to overcome at least one of the above-mentioned defects in the prior art to improve the braking performance of a vehicle.

[0005] An embodiment of the present invention provides a method for brake boosting of a vehicle, comprising: determining, by a determination unit of the vehicle, whether a brake booster of the vehicle is in a failed state; in response to determining that the brake booster is in a normal state, instructing the brake booster to provide brake boosting during the braking process of the vehicle, by a control unit of the vehicle; and in response to determining that the brake booster is in a failed state and in the absence of measuring the pressure applied by the driver on the brake pedal, providing additional brake force boosting during the braking process of the vehicle to achieve the required deceleration, by the control unit of the vehicle, wherein, in response to the instruction of the control unit, the vehicle performs the following operations: State acquisition step: through the electronic body The diagnostic event management module DEM of the electronic control unit ECU of the stability control system ESP collects the state of the hydraulic brake booster system HBB; the pressure collection step: the brake master cylinder pressure pMC is collected by the brake master cylinder pressure sensor; the state judgment step: judge whether the state of the HBB is the full operation mode of the hydraulic booster failure compensation system HBC; the pressure determination step: when it is judged that the state of the HBB is not in the HBC full operation mode, determine that the driver's applied pressure is equal to the pMC; the pressure transmission step: transmit the determined driver's applied pressure to the ECU of the ESP; the identifier acquisition step: when it is judged that the state of the HBB is in the HBC full operation mode, collect the signal s0 from the brake booster utputRodDriver to obtain its identifier sOutputRodDriver_Q; identifier judgment step: judging whether the identifier sOutputRodDriver_Q is "Inputrod", when it is judged that the identifier sOutputRodDriver_Q is not "Inputrod", executing the pressure determination step (310); pedal position acquisition step (307): when it is judged that the identifier sOutputRodDriver_Q is "Inputrod", obtaining the brake pedal position according to the brake booster input rod position information in the sOutputRodDriver signal and the first calibration parameter table, the A first calibration parameter indicates the correspondence between the position of the input rod and the brake pedal position; a brake request pressure obtaining step: obtaining the driver's brake request pressure according to the obtained brake pedal position and a second calibration parameter table, wherein the second calibration parameter indicates the correspondence between the brake pedal position and the driver's request pressure; a target brake pressure obtaining step: comparing the obtained driver's brake request pressure with the actual pMC, and using the maximum value between the two as the target brake pressure applied by the driver; and a target brake pressure transmission step: transmitting the determined target brake pressure applied by the driver to the relevant control unit of the ESP, and the actuator of the ESP system completes the corresponding brake boost failure compensation.

[0006] An embodiment of the present invention provides a device for brake boosting of a vehicle, comprising: a determination unit, configured to determine whether a brake booster of the vehicle is in a failed state; a control unit, in response to determining that the brake booster is in a normal state, instructing the brake booster to provide brake boosting during the braking process of the vehicle; and in response to determining that the brake booster is in a failed state and in the absence of measuring the pressure applied by the driver on the brake pedal, instructing a device in the vehicle that can provide additional brake boosting to serve as a brake boosting compensation unit, to provide additional brake boosting during the braking process of the vehicle to achieve the required deceleration, wherein, in response to the instruction of the control unit The vehicle performs the following operations: a state acquisition step: acquiring the state of the hydraulic brake booster system HBB through the diagnostic event management module DEM of the electronic control unit ECU of the electronic body stability control system ESP; a pressure acquisition step: acquiring the brake master cylinder pressure pMC by the brake master cylinder pressure sensor; a state judgment step: judging whether the state of the HBB is the full operation mode of the hydraulic booster failure compensation system HBC; a pressure determination step: when it is judged that the state of the HBB is not in the HBC full operation mode, determining that the driver's applied pressure is equal to the pMC; a pressure transmission step: transmitting the determined driver's applied pressure to the ECU of the ESP; an identifier acquisition step : When it is determined that the state of the HBB is in the HBC full operation mode, the signal sOutputRodDriver is collected from the brake booster to obtain its identifier sOutputRodDriver_Q; identifier judgment step: judging whether the identifier sOutputRodDriver_Q is "Inputrod", when it is determined that the identifier sOutputRodDriver_Q is not "Inputrod", the pressure determination step (310) is executed; pedal position acquisition step (307): when it is determined that the identifier sOutputRodDriver_Q is "Inputrod", the pedal position acquisition step (307) is executed. ", the brake pedal position is obtained according to the brake booster input rod position information in the sOutputRodDriver signal and the first calibration parameter table, wherein the first calibration parameter indicates the corresponding relationship between the position of the input rod and the brake pedal position; a brake request pressure obtaining step: obtaining the driver's brake request pressure according to the obtained brake pedal position and the second calibration parameter table, wherein the second calibration parameter indicates the corresponding relationship between the brake pedal position and the driver's request pressure; a target brake pressure obtaining step: comparing the obtained driver's brake request pressure with the actual pMC, and using the maximum value of the two as the target brake pressure applied by the driver;and a target braking pressure transmission step: transmitting the determined target braking pressure applied by the driver to the relevant control unit of the ESP, and the actuator of the ESP system completes the corresponding brake boost failure compensation. ;

[0007] An embodiment of the present invention provides a controller, comprising: one or more processors; and a memory having executable instructions stored thereon; when the executable instructions are executed, the one or more processors execute the method for brake assist for a vehicle according to the above-mentioned embodiment of the present invention.

[0008] An embodiment of the present invention provides a machine-readable storage medium having executable instructions stored thereon; when the executable instructions are executed, the machine is enabled to execute the method for brake assisting of a vehicle according to the embodiment of the present invention described above.

[0009] An embodiment of the present invention provides a system for brake assisting of a vehicle, comprising: a brake booster configured to provide brake assisting during the braking process of the vehicle; a first sensor configured to detect whether the brake booster is in a failed state; and a controller connected to the brake booster and the first sensor and configured to generate a control signal for causing the brake booster to provide brake assisting when the brake booster is in a normal state, at least in part based on sensor data from the first sensor; and to generate a control signal for providing additional brake force assisting during the braking process of the vehicle, at least in part based on sensor data from the first sensor when the brake booster is in a failed state and no pressure applied by the driver on the brake pedal is measured.

[0010] An embodiment of the present invention further provides an electronic vehicle stability control system, comprising the controller described in the above embodiment of the present invention.

[0011] Embodiments of the present invention can improve the braking performance of a vehicle, including but not limited to providing timely and accurate brake boost compensation when a brake booster fails, ensuring driving safety, and improving the driving experience, even without measuring the pressure applied by the driver on the brake pedal. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 A flow chart of a method for vehicle brake boosting according to an embodiment of the present invention is shown;

[0013] Figure 2 A structural block diagram of a device for vehicle brake boosting according to an embodiment of the present invention is shown;

[0014] Figure 3An example flow chart showing an electronic vehicle stability control system determining a target brake pressure and providing brake assist when a brake booster fails in an embodiment of the present invention; and

[0015] Figure 4 A structural block diagram of a system for brake boosting of a vehicle according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0016] The embodiments of the present invention are further described below in conjunction with the accompanying drawings.

[0017] Figure 1 A flow chart of an embodiment of a method for vehicle brake boosting of the present invention is shown, the method 100 comprising: detecting the working state of a brake booster of a vehicle during braking (step 110); determining whether the brake booster is in a failed state (step 120); in response to determining that the brake booster is in a normal state, instructing the brake booster to provide brake boosting during the braking process of the vehicle (step 130); and in response to determining that the brake booster is in a failed state, providing additional brake force boosting during the braking process of the vehicle to achieve the desired deceleration (step 140).

[0018] According to an embodiment of the present invention, step 140 of providing additional braking force assistance includes: measuring the position of an input rod of a brake booster; the position of the input rod indicates a driver's braking request, which corresponds to the driver's operation of stepping on a brake pedal; based on the measured position of the input rod, calculating a target pressure corresponding to the brake pedal position; and providing the calculated target pressure as additional braking force assistance.

[0019] According to an embodiment of the present invention, method 100 may also include: when it is determined that the brake booster of the vehicle is in a failure state, sending information about the failure state of the brake booster and input rod position information to a device in the vehicle that can provide additional braking force assistance via a CAN (vehicle controller area network) bus; and generating a calculated target braking pressure by the device, and applying the generated target braking pressure to the brake pedal.

[0020] According to an embodiment of the present invention, the method 100 may further include: for example, after determining that the brake booster is in a normal state, determining whether the brake booster is in a communication interruption state, such as a CAN failure or a communication interruption between the brake booster and the electronic vehicle stability control system, etc.; in response to determining that the brake booster is in a communication interruption state, stopping the brake booster of the brake booster; and providing additional braking force assistance to achieve the required deceleration. Thus, even if the state of the brake booster cannot be transmitted in time when a CAN failure occurs, for example, braking force compensation can still be provided, avoiding the problem of being unable to provide braking force compensation in time when the brake booster fails due to a communication failure.

[0021] According to an embodiment of the present invention, the device that can provide additional braking force assistance in the vehicle is an electronic body stability control system. However, the present invention is not limited thereto, and for example, it may also be an intelligent integrated braking (IPB) system or a redundant braking unit (RBU). The electronic body stability control system used in the embodiment of the present invention may be, for example, an electronic stability program (ESP) system for body control, an electronic stability control (ESC) system, a vehicle stability control (VSC) system, etc.

[0022] According to an embodiment of the present invention, the step of calculating the target pressure in step 140 includes: based on a first calibration parameter, converting the measured position of the input rod into a brake pedal position, the first calibration parameter indicating the correspondence between the position of the input rod and the brake pedal position; based on a second calibration parameter, converting the converted brake pedal position into a driver-requested brake pressure, the second calibration parameter indicating the correspondence between the brake pedal position and the driver-requested brake pressure; and selecting the maximum value of the driver-requested brake pressure and the brake master cylinder pressure as the target brake pressure.

[0023] According to an embodiment of the present invention, the first calibration parameter and the second calibration parameter may be adjusted according to the braking requirement.

[0024] Figure 2 The structural block diagram of the device for vehicle brake boosting according to an embodiment of the present invention is shown. The device 200 includes: a determination unit 210, configured to determine whether a brake booster 230 of the vehicle is in a failed state; a control unit 220, in response to determining that the brake booster 230 is in a normal state, instructing the brake booster 230 to provide brake boosting during the braking process of the vehicle; and in response to determining that the brake booster 230 is in a failed state, instructing a device 240 in the vehicle that can provide additional brake boosting to serve as a brake boosting compensation unit, providing additional brake boosting during the braking process of the vehicle to achieve the required deceleration.

[0025] According to an embodiment of the present invention, in response to the instruction of the control unit 220, the device 240 performs the following operations: receiving the measured position of the input rod of the brake booster 230, the position of the input rod indicating the driver's braking request; calculating a target pressure corresponding to the brake pedal position based on the measured position of the input rod; and providing the calculated target pressure as an additional braking force booster.

[0026] According to an embodiment of the present invention, when the determination unit 210 determines that the brake booster 120 of the vehicle is in a failed state, information about its failed state and input rod position information are sent to a device 140 in the vehicle that can provide additional braking force assistance via the CAN bus; the control unit 220 instructs the device 240 to act as a brake booster compensation unit, generate a calculated target pressure, and apply the generated target pressure to the brake pedal of the vehicle to achieve braking.

[0027] According to an embodiment of the present invention, the determination unit 210 is also configured to determine whether the brake booster 230 is in a communication interruption state; and in response to determining that the brake booster is in a communication interruption state, the control unit 220 causes the brake booster 230 to stop the brake assist during the braking process, and instructs the device 240 to provide additional braking force assistance to achieve the required deceleration.

[0028] Device 240 may be an electronic stability control system or other system in a vehicle that can provide additional braking force assistance.

[0029] According to an embodiment of the present invention, in response to the instruction of the control unit 220, the device 240 can perform the following operations: based on a first calibration parameter, convert the measured position of the input rod into a brake pedal position, the first calibration parameter indicating the correspondence between the position of the input rod and the brake pedal position; and based on a second calibration parameter, convert the converted brake pedal position into a driver-requested brake pressure as a target pressure, the second calibration parameter indicating the correspondence between the brake pedal position and the driver-requested brake pressure.

[0030] According to an embodiment of the present invention, a solution is provided for improving brake boost compensation by combining a brake booster failure compensation unit (e.g., an ESP system) with a brake booster (hereinafter, Bosch's iBooster or eBooster is used as an example, but the present invention is not limited thereto). When the brake booster fails, the failure compensation unit (e.g., the brake booster system HBB / HBC in the ESP system) needs to provide additional braking force assistance so that a specified minimum deceleration is generated by a specified pedal force on the brake pedal (e.g., 2.44 m / s is generated by a brake pedal force of 500 N). 2 The active pressure established by the ESP system increases the pressure in the brake line to achieve the required minimum deceleration with less pedal force.

[0031] In one embodiment, a brake booster (such as iBooster) may include: an input rod connected to a brake pedal, a booster valve body, a pedal travel sensor for sensing the brake pedal travel, a return spring for restoring the brake pedal position, a brake master cylinder for establishing brake hydraulic pressure, a DC brushless motor as a booster power source, a secondary gear transmission device for increasing the transmission ratio and torque, and an electronic control unit for controlling the motor power supply current and drive signal. During operation, the pedal travel sensor detects the displacement of the booster input rod and sends the displacement signal to the control unit; the control unit calculates the torque requirement that the motor should generate, and the secondary gear transmission device converts the torque into the servo braking force of the booster valve body; finally, the boost generated by the motor and the force applied by the driver on the input rod are converted into brake hydraulic pressure in the brake master cylinder. In one embodiment, the electronic control unit of a brake booster (such as iBooster) includes the following units: braking force boost (BFB), external brake request-execution (EBR-E), brake light activation-full system (BLA-F), system status processing-iBooster (SSH-iB), pedal force compensation-execution (PFC-E), pressure reduction logic (PRL), driver brake request-braking force (DBR-F) and human-machine interface-iB (HMI-iBooster) and other units.

[0032] The embodiments of the present invention are not only applicable to brake boosters that generate servo braking force through motors, but also applicable to brake boosters that use vacuum assistance. However, they need to be equipped with additional sensors, such as working status sensors, position sensors of booster push rods that can be pushed by the force from the brake pedal, etc.

[0033] ESP system or ESC system can be used to control the stability of the vehicle body. Its basic function is to monitor the driving state of the vehicle and prevent the vehicle from deviating from the ideal trajectory when understeering or oversteering occurs during emergency avoidance of obstacles or turns. ESP system can include anti-lock braking system (ABS), brake assist system (BAS) and anti-skid system (ASR). Specifically, ESP system mainly consists of four parts: sensor part for detecting vehicle status and driver operation; ECU part for estimating vehicle side slip state and calculating rotational momentum and deceleration required to restore to a safe state; actuator part for controlling the braking force of each wheel and engine output power according to the calculation results; information part for informing the driver of vehicle instability.

[0034] The ECU control part in the ESP system or ESC system may include the following units: basic controller (such as anti-lock braking system ABS, vehicle dynamic control system VDC, traction control system TCS), longitudinal dynamic management (LDM), hydraulic booster failure compensation (HBC), brake torque coordination (BTC), brake light activation-standby (BLA-B), driver brake request-brake torque (DBR-T), hydraulic brake boost (HBB), system status processing (SSH-E), external brake request-controller (EBR-C) and human-machine interface (HMI-E) and other units. The brake booster can transmit various signals to the ESP (or ESC) system, such as iBSCCompatiBilityIndex, HBCRequest, iBDiagActive, BrakePedalApplied (Q), pRunout (Q), sOutputRodDriver (Q), etc. The ESP system or ESC system can also transmit various signals to the brake booster, such as pMC1 (Q), VehicleSpeed ​​(Q), AbsActive, pEstMax, etc.

[0035] The HBB and HBC functional modes are value-added functions for dynamic brake pressure boost for vehicles equipped with a hydraulic brake system, a booster (such as a vacuum booster) and an Electronic Stability Program (ESP) system.

[0036] In one embodiment, when the vehicle needs to brake, the driver steps on the brake pedal, and the input rod of the brake booster will produce a corresponding displacement. The brake booster can provide its output rod position to the ESP system, and the driver brake request (DBR) unit in the ESP system can convert the output rod position information of the brake booster into the driver's target braking force information (FxTargetDriver). When the brake booster (iBooster) fails due to a mechanical failure (such as a motor failure) or a failure of the RPS (on-board redundant power supply), if there is no communication failure between the ESP system and the brake booster, its failure state and boost compensation request (HBCRequest) can be transmitted to the ESP or ESC system through the CAN (controller area network) bus, and the booster state is set to a mechanical standby / failure boost mode. When the on-board power supply fails (i.e., in the power-off mode), for example, a mechanical driving force can be used as a backup, that is, the driver can apply wheel brakes to all four wheels in a pure hydraulic mode without brake boost to stop the vehicle safely. When the brake booster fails, the status information of the brake booster will indicate that the brake booster is in fail-safe mode, and the status of HBB will be changed to HBC; at this time, the HBC request signal (HBCRequest) is set to "TRUE", and the brake booster can measure the input rod position of the brake booster by using the pedal travel sensor (PTS) or linear position sensor (LiPS). Then, using the sensor's detection data and the brake master cylinder pressure (pMC) information, the driver's target brake pressure can be calculated.

[0037] In case of brake booster failure, the ESP system will take over and provide brake boost. When the ESP system receives the iBooster failure status and HBC request from the brake booster, the ESP system will switch from HBB to HBC full operation mode. In this case, the output rod position indicator is invalid and the DBR unit is closed (TargetStateDBR).

[0038] When the brake booster is in a failed state, it can measure the driver's braking request at its input rod, unless there is a problem with the pedal travel sensor or the sensor power supply. The brake booster will use any available interface signal (such as the signal sOutputRodDriver) to transmit input rod movement information indicating the driver's braking request to the ESP system. Using such an existing interface signal (such as sOutputRodDriver) makes it unnecessary to define additional interface information.

[0039] Once the ESP system receives the input rod movement information, it will calculate and convert the input rod movement information into the driver pedal position information in percentage. The ESP system will calculate the brake target pressure corresponding to the driver pedal position. This method can effectively calculate the driver's brake target pressure even if the driver's movement on the brake pedal is small. Therefore, the driver does not need to step on the brake pedal hard. The ESP system can also use, for example, the hydraulic pump and the brake master cylinder therein to generate the required pressure to activate the HBC.

[0040] During the brake booster failure state, the input rod position information will be sent to the ESP. For this purpose, in one example, the brake booster can use the current signal sOutputRodDriver, which is usually information indicating the driver's braking request, which can also indicate the pedal travel under the active pressure boost by the brake booster by calculating the target value of the output rod in the brake booster; and during the brake booster failure, the signal can be used to indicate its input rod position for HBC. For example, the brake booster can set the identifier sOutputRodDriver_Q in the sOutputRodDriver signal to have the following state information values: 0 (indicating uninitialized state), 1 (indicating normal state), 2 (indicating fault state), 3 (indicating input rod state). When the brake booster is in a failed state and the brake pedal travel sensor can measure without any electrical fault, the identifier is set to "3-Input rod (Inputrod)", and the signal sOutputRodDriver indicates the input rod position information of the brake booster (sOutputRodDriver_Q=Inputrod). When the brake booster is in a failed state and the brake pedal travel sensor fails due to any electrical fault, the identifier is set to "2-Fault", that is, the signal sOutputRodDriver indicates that a fault state occurs.

[0041] In another embodiment, under normal operating conditions, the ESP system will receive an updated frame format for the signal sOutputRodDriver_Q from the brake booster. When communication with the brake booster is interrupted or the brake booster fails or is turned off (HBCRequest=True), the ESP system will change from HBB mode to HBC mode.

[0042] In one embodiment, the ESP system in the HBC full operation mode will change the way it detects the pressure applied by the driver, as follows:

[0043] ESP will receive the sOutputRodDriver signal sent by the brake booster; ESP will check the sOutputRodDriver_Q identifier indicating additional information to decide whether to use the sOutputRodDriver signal; when it is determined that sOutputRodDriver_Q = Inputrod, ESP will use a one-dimensional calibration parameter table (first calibration parameter) to convert sOutputRodDriver to the corresponding brake pedal position; ESP will use a one-dimensional calibration parameter table (second calibration parameter) to calculate the driver's brake request pressure based on the brake pedal position; compare the calculated pressure with the actual master cylinder pressure pMC, and use the maximum value of the calculated pressure and pMC as the input pressure for calculating the HBC target pressure. This is used to perform a failsafe operation when the calculated pressure is less than the actual pressure pMC.

[0044] In one embodiment, a first calibration parameter table for converting the input rod position from the brake booster to the brake pedal position is shown in Table 1 below:

[0045] Table 1:

[0046]

[0047] For example, when the input rod position is at 1 mm, the corresponding brake pedal position (or percentage of downward depression relative to full depression) is 25%.

[0048] In one embodiment, a second calibration parameter table for converting brake pedal position to driver brake request pressure is shown in Table 2 below. It is derived from the driver brake request (DBR).

[0049] Table 2:

[0050]

[0051] For example, when the brake pedal position is 30%, the corresponding driver-requested brake pressure is 25 bar. It should be noted that the driver-requested brake pressure obtained here is a virtual calculated value, not an actual measured value.

[0052] The calculation of the target pressure corresponding to the brake pedal position is based on Table 1 and Table 2 above. The above one-dimensional parameter table can be adjusted by the application engineer according to user requirements (e.g., according to road conditions, vehicle conditions, weather, braking requirements, etc.). This adjustment is one of the functions of the driver brake request (DBR) unit. Using the above two calibration parameter tables, the target pressure corresponding to the driver's brake request can be accurately calculated to provide timely and accurate braking force compensation when the brake booster fails, thereby avoiding panic braking and improving the driving experience.

[0053] Three different HBB / HBC operating modes can be used in the brake booster: HBB overboost mode in the event of a gradual brake failure, HBC full operating mode in the event of a passive brake booster, and HBC reduced mode in the event of a CAN bus failure. Both the HBB and HBC functions require information about the state of the brake booster and a signal that the brake booster is running down (Runout). This information is usually transmitted via the CAN bus.

[0054] In the above three modes, the diagnostic module of the ESP system can obtain the status information of the brake booster from the brake booster and provide the corresponding control signal (TargetStateHBB) to the HBB unit; the HBB unit generates the target pressure according to the control signal and the master cylinder pressure, and then the actuator applies the corresponding braking force to the vehicle.

[0055] As an example, the following combination Figure 3 Describes the process by which the ESP system determines the target brake pressure and provides brake assistance when the brake booster fails.

[0056] The process starts (step 301),

[0057] First, the HBB status is collected from a DEM (diagnostic event management) module of an ECU (electronic control unit) of an ESP system, for example (step 302);

[0058] The master cylinder pressure (pMC) is collected by the master cylinder pressure sensor (step 303);

[0059] Determine whether the state of HBB is HBC full operation mode (step 304);

[0060] When it is determined that the state of the HBB is not in the HBC full operation mode, determining that the driver applied pressure is equal to the master cylinder pressure (step 310);

[0061] The determined driver applied pressure is transmitted to a control unit of the ESP system (step 311 ).

[0062] When it is determined that the state of the HBB is in the HBC full operation mode, a signal sOutputRodDriver is collected from the brake booster (iBooster) to obtain its identifier sOutputRodDriver_Q (step 305);

[0063] Determine whether the identifier sOutputRodDriver_Q is "Inputrod" (step 306);

[0064] When it is determined that the identifier sOutputRodDriver_Q is not “Inputrod”, it means that the sOutputRodDriver signal does not contain the input rod position information of the brake booster, and then step 310 is executed, and then the process goes to step 311 .

[0065] When it is determined that the identifier sOutputRodDriver_Q is "Inputrod", it means that the brake booster is in a failed state and the brake pedal travel sensor can measure without any electrical fault, then the brake pedal position is obtained according to the brake booster input rod position information in the sOutputRodDriver signal and the first calibration parameter table (step 307);

[0066] Obtain the driver's brake request pressure according to the obtained brake pedal position and the second calibration parameter table (step 308);

[0067] The obtained driver's brake request pressure is compared with the actual master cylinder pressure pMC, and the maximum value between the two is used as the target brake pressure applied by the driver (step 309);

[0068] Then, step 311 is executed to transmit the determined target brake pressure applied by the driver to the relevant control unit of the ESP system.

[0069] Therefore, even if the pressure applied by the driver on the brake pedal is not measured, the target pressure corresponding to the driver's braking request can be accurately calculated, and the corresponding brake boost failure compensation can be completed by the actuator of the ESP system.

[0070] Figure 4 A structural block diagram of a system for brake assisting of a vehicle according to an embodiment of the present invention is shown, the system 400 comprising: a brake booster 410, configured to provide brake assisting during the braking process of the vehicle; a first sensor 412, configured to detect whether the brake booster 410 is in a failed state; and a controller 420, which connects the brake booster 410 and the first sensor 412 and is configured to generate a control signal for enabling the brake booster 410 to provide brake assisting based at least in part on sensor data from the first sensor 412; and to generate a control signal for providing additional brake force assisting during the braking process of the vehicle based at least in part on the sensor data from the first sensor 412.

[0071] According to an embodiment of the present invention, the system 400 may further include: a device 430 (e.g., an electronic vehicle stability control system) that can provide additional braking force assistance; a second sensor 414 configured to detect the position of an input rod of the brake booster 410. The controller 420 provides a control signal for providing additional braking force assistance during the braking process of the vehicle to the device 430; the device 430 is also configured to calculate a target pressure corresponding to a driver's braking request when the brake booster 410 is detected to be in a failed state during the braking process of the vehicle based at least in part on the sensor data from the first sensor 412 and the second sensor 414, and provide the calculated target pressure as the braking force.

[0072] Those skilled in the art should understand that the controller 420 may be one or more independent controllers, or may be implemented inside or combined with a controller in the brake booster 410 and / or a controller in the device 430 .

[0073] An embodiment of the present invention further provides an electronic vehicle stability control system, comprising the controller described in the above embodiment of the present invention. The electronic vehicle stability control system can be configured to provide additional braking force assistance during vehicle braking when the brake booster is in a failed state based on at least one of the state information of the brake booster, the input rod position information of the brake booster, and the brake master cylinder pressure, so as to achieve the desired vehicle deceleration.

[0074] The above are preferred embodiments of the present invention, but the disclosed contents are illustrative only, and the technical solutions of the present invention are not limited to the above embodiments. For ordinary technicians in this field, various modifications and variations can be made to the above embodiments based on the general principles defined by the above disclosed contents, and these modifications and variations should all fall within the scope of protection of this patent.

Claims

1. A method for brake boosting of a vehicle, comprising: Determining, by a determination unit of the vehicle, whether a brake booster of the vehicle is in a failed state; In response to determining that the brake booster is in a normal state, instructing the brake booster to provide brake boosting during braking of the vehicle by a control unit of the vehicle; as well as In response to determining that the brake booster is in a failed state and without measuring the pressure applied by the driver on the brake pedal, the control unit provides additional braking force assistance during the braking process of the vehicle to achieve the required deceleration, Wherein, in response to the instruction of the control unit, the vehicle performs the following operations: State collection step (302): collecting the state of the hydraulic brake booster system HBB through the diagnostic event management module DEM of the electronic control unit ECU of the electronic vehicle stability control system ESP; Pressure collection step (303): collecting the brake master cylinder pressure pMC by the brake master cylinder pressure sensor; State determination step (304): determining whether the state of the HBB is the full operation mode of the hydraulic booster failure compensation system HBC; Pressure determination step (310): when it is determined that the state of the HBB is not in the HBC full operation mode, determining that the driver applied pressure is equal to the pMC; A pressure transmission step (311): transmitting the determined driver applied pressure to the ECU of the ESP; Identifier acquisition step (305): when it is determined that the state of the HBB is in the HBC full operation mode, collecting a signal sOutputRodDriver from the brake booster to obtain its identifier sOutputRodDriver_Q; Identifier determination step (306): determining whether the identifier sOutputRodDriver_Q is "Inputrod", and when it is determined that the identifier sOutputRodDriver_Q is not "Inputrod", executing the pressure determination step (310); Pedal position obtaining step (307): when it is determined that the identifier sOutputRodDriver_Q is "Inputrod", the brake pedal position is obtained according to the brake booster input rod position information in the sOutputRodDriver signal and a first calibration parameter table, wherein the first calibration parameter indicates the corresponding relationship between the position of the input rod and the brake pedal position; A brake request pressure obtaining step (308): obtaining a driver's brake request pressure according to the obtained brake pedal position and a second calibration parameter table, wherein the second calibration parameter indicates a corresponding relationship between the brake pedal position and the driver's brake request pressure; Target brake pressure obtaining step (309): comparing the obtained driver brake request pressure with the actual pMC, and using the maximum value between the two as the target brake pressure applied by the driver; and Target brake pressure transmission step (311): The determined target brake pressure applied by the driver is transmitted to the relevant control unit of the ESP, and the actuator of the ESP system completes the corresponding brake boost failure compensation.

2. The method according to claim 1, further comprising: determining whether the brake booster is in a communication interruption state; In response to determining that the brake booster is in a communication interruption state, stopping the brake booster from providing brake assistance during braking; and The additional braking force assist is provided to achieve the required deceleration.

3. A device for boosting brakes of a vehicle, comprising: a determination unit configured to determine whether a brake booster of the vehicle is in a failed state; a control unit, in response to determining that the brake booster is in a normal state, instructing the brake booster to provide brake boosting during braking of the vehicle; and in response to determining that the brake booster is in a failed state and in the absence of measuring the pressure applied by the driver on the brake pedal, instructing a device in the vehicle that can provide additional braking force assistance as a brake boost compensation unit to provide additional braking force assistance during the braking process of the vehicle to achieve the required deceleration, Wherein, in response to the instruction of the control unit, the vehicle performs the following operations: State collection (302): collecting the state of the hydraulic brake booster system HBB through the diagnostic event management module DEM of the electronic control unit ECU of the electronic vehicle stability control system ESP; Pressure acquisition (303): the brake master cylinder pressure pMC is acquired by the brake master cylinder pressure sensor; State determination (304): determining whether the state of the HBB is the full operation mode of the hydraulic booster failure compensation system HBC; Pressure determination (310): when it is determined that the state of the HBB is not in the HBC full operation mode, determining that the driver applied pressure is equal to the pMC; Pressure transmission (311): transmitting the determined driver applied pressure to the ECU of the ESP; Identifier acquisition (305): when it is determined that the state of the HBB is in the HBC full operation mode, collecting a signal sOutputRodDriver from the brake booster to obtain its identifier sOutputRodDriver_Q; Identifier determination (306): determining whether the identifier sOutputRodDriver_Q is "Inputrod", and when it is determined that the identifier sOutputRodDriver_Q is not "Inputrod", executing the pressure determination step (310); Pedal position acquisition (307): when it is determined that the identifier sOutputRodDriver_Q is "Inputrod", the brake pedal position is obtained according to the brake booster input rod position information in the sOutputRodDriver signal and a first calibration parameter table, wherein the first calibration parameter indicates the corresponding relationship between the position of the input rod and the brake pedal position; The brake request pressure is obtained (308): the driver's brake request pressure is obtained according to the obtained brake pedal position and a second calibration parameter table, wherein the second calibration parameter indicates a corresponding relationship between the brake pedal position and the driver's request pressure; Target brake pressure is obtained (309): the obtained driver brake request pressure is compared with the actual pMC, and the maximum value between the two is used as the target brake pressure applied by the driver (step 309); and Target brake pressure transmission (311): The determined target brake pressure applied by the driver is transmitted to the relevant control unit of the ESP, and the actuator of the ESP system completes the corresponding brake boost failure compensation.

4. The device according to claim 3, wherein: The determination unit is further configured to determine whether the brake booster is in a communication interruption state; In response to determining that the brake booster is in the communication interruption state, the control unit causes the brake booster to stop the brake boosting during braking and instructs the device to provide the additional braking force boosting to achieve the required deceleration.

5. A controller comprising: one or more processors; as well as A memory having executable instructions stored therein; When the executable instructions are executed, the one or more processors are caused to perform the method of claim 1 or 2.

6. A machine-readable storage medium having executable instructions stored thereon; when the executable instructions are executed, the machine is enabled to execute the method of claim 1 or 2.

7. An electronic vehicle stability control system, comprising the controller according to claim 5.

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