Fault detection method, computer program product, storage medium, vehicle controller and vehicle

Abstract

The invention provides a fault detection method, a computer program product, a storage medium, a vehicle controller and a vehicle, according to the fault detection method provided by the invention, when communication between a brake adjusting unit and a brake execution unit carried by the vehicle is abnormal, a first pressure value of a brake master cylinder at the position of the vehicle is obtained; and after it is determined that the brake master cylinder should have a second pressure value under the current brake pedal stroke of the vehicle, a fault detection result for the brake execution unit can be generated according to the difference between the first pressure value and the second pressure value.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle braking, in particular to a fault detection method, a computer program product, a storage medium, a vehicle controller and a vehicle. BACKGROUND

[0002] With the continuous development of vehicle braking technology, One Box and Two Box braking systems have emerged. Among them, the One Box braking system can integrate the vehicle-mounted brake adjustment unit and the brake execution unit in one, which not only saves space, but also improves the brake response speed. The Two Box braking system can independently arrange the brake adjustment unit and the brake execution unit, and through redundant design, even if part of the system fails, the basic braking function can still be realized to provide more stable braking performance. However, at present, when a communication failure occurs between the brake adjustment unit and the brake execution unit in the Two Box braking system, it is usually impossible to identify whether the brake execution unit can still normally provide brake force assistance. This will directly affect the accuracy of the brake adjustment unit when performing brake control, thereby easily leading to problems such as over-braking or reduced braking performance, and thus threatening the safety of vehicle driving. SUMMARY

[0003] Based on this, the present application provides a fault detection method, a computer program product, a storage medium, a vehicle controller and a vehicle. By using the fault detection method, when a communication abnormality occurs between the brake adjustment unit and the brake execution unit mounted on the vehicle, an accurate fault detection result for the brake execution unit can be generated, which is beneficial to guarantee the safety of the vehicle during operation.

[0004] In one aspect, the present application provides a fault detection method, which comprises: When a communication abnormality occurs between the brake adjustment unit and the brake execution unit mounted on the vehicle, obtaining a first pressure value of a brake master cylinder at the vehicle; Determining a second pressure value that the brake master cylinder should have under the current brake pedal stroke of the vehicle; According to the difference between the first pressure value and the second pressure value, generating a fault detection result for the brake execution unit.

[0005] In another aspect, the present application also provides a computer program product comprising a computer program, which, when executed, implements the steps of the above-mentioned fault detection method.

[0006] In another aspect, the present application also provides a storage medium having a computer program stored thereon, which, when executed, implements the steps of the above-mentioned fault detection method.

[0007] In another aspect, the application also provides a vehicle controller, comprising: a processor and a memory; wherein the memory stores a computer program which is adapted to be loaded and executed by the processor to perform the steps of the above fault detection method.

[0008] In another aspect, the application also provides a vehicle, comprising: a brake adjustment unit, a brake execution unit, and the above vehicle controller.

[0009] According to the fault detection method provided by the application, when the communication between the brake adjustment unit and the brake execution unit mounted on the vehicle is abnormal, the first pressure value of the brake master cylinder at the vehicle can be obtained; and the second pressure value of the brake master cylinder under the current brake pedal stroke of the vehicle can be determined. By the difference between the first pressure value and the second pressure value, an accurate fault detection result for the brake execution unit can be generated conveniently and quickly, which is beneficial to the safety of the vehicle during operation.

[0010] It should be understood that the content described in the summary section is not intended to limit the key or important features of the embodiments of the application, nor to limit the scope of the application. Other features of the application will become apparent through the following description. BRIEF DESCRIPTION OF DRAWINGS

[0011] Figure 1 A flowchart of a fault detection method provided by an embodiment of the application; Figure 2 A structural diagram of a vehicle brake system provided by an embodiment of the application; Figure 3 A structural diagram of a vehicle controller provided by an embodiment of the application. DETAILED DESCRIPTION

[0012] In order to make the purpose, technical scheme and advantages of the application clearer, the technical scheme of the application will be described clearly and completely below by combining the specific embodiments of the application with the corresponding drawings. Obviously, the described embodiments are only some of the embodiments of the application, not all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the application. The order of some steps in the method provided by one or more embodiments of the application can be exchanged according to actual needs, or some steps can be omitted or deleted, and this is not specifically limited.

[0013] In the description of one or more embodiments of the application, the term "includes" and its variants are to be read as open-ended terms that mean "includes, but is not limited to." The term "based on" is to be read as "based, at least in part, on." The term "one embodiment" or "an embodiment" are to be read as "at least one embodiment." The term "first," "second," and the like, can refer to different or the same objects. Other explicit or implicit definitions can also be included below.

[0014] The term "at least one" is to be taken as including one and more than one, for example, "at least one of A and B" can include "A alone," "B alone," and "A and B." Other explicit or implicit definitions can also be included below, without being specifically limited.

[0015] In the description of one or more embodiments of the application, the term "and / or" is to be understood as including one and more than one, for example, "A and / or B" can include "A alone," "B alone," and "A and B." Other explicit or implicit definitions can also be included below, without being specifically limited.

[0016] Two-box brake system can be referred to as "double-box brake system", the core feature of which can be that the brake adjustment unit and the brake execution unit are independent of each other and arranged separately. By dividing the brake adjustment unit and the brake execution unit, the brake performance, redundancy safety and functional expansion can be balanced, which is widely used in traditional fuel vehicles, hybrid electric vehicles and new energy vehicles. Among them, the brake adjustment unit can belong to the brake control center, responsible for signal processing, strategy calculation and instruction sending, while the brake execution unit can belong to the main brake actuator, which receives and executes the instructions sent by the brake adjustment unit, so as to convert the brake intention of the driver into brake force. In addition, the brake adjustment unit can also have safety redundancy capability, which can actively take over the brake assist when the brake function of the brake execution unit fails, so as to meet the emergency braking force of the vehicle.

[0017] However, at present, when a communication fault occurs between the brake regulating unit and the brake executing unit, it is generally impossible to identify whether the brake executing unit can still normally provide brake force assistance. In this case, if the brake regulating unit provides full brake support, but the brake executing unit can still normally provide brake force assistance, an over-braking situation may occur; and if the brake regulating unit does not provide full brake support, but the brake executing unit cannot normally provide brake force assistance, the vehicle braking performance may be reduced, affecting the vehicle driving safety.

[0018] Based on this, when a communication abnormality occurs between the brake regulating unit and the brake executing unit carried by the vehicle, how to accurately generate a fault detection result for the brake executing unit has become a problem to be solved.

[0019] The present application provides a fault detection method, which can acquire a first pressure value of a brake master cylinder at the vehicle when a communication abnormality occurs between the brake regulating unit and the brake executing unit carried by the vehicle; and determine a second pressure value that the brake master cylinder should have under a current brake pedal stroke of the vehicle; by the difference between the first pressure value and the second pressure value, an accurate fault detection result for the brake executing unit can be generated conveniently and quickly, which is beneficial to guarantee the safety of the vehicle during operation.

[0020] Please refer to Figure 1 , a flowchart of a fault detection method provided by the embodiment of the present application. From the program point of view, the execution subject of the flowchart can be a program carried by the brake regulating unit, the vehicle controller or the vehicle. Alternatively, the execution subject of the flowchart can also be the brake regulating unit, the vehicle controller or the vehicle, or other devices capable of communicating with the brake regulating unit, the vehicle controller or the vehicle, which is not specifically limited.

[0021] The following will be described in detail with respect to the flowchart shown in Figure 1 The fault detection method can specifically include the following steps: Step S102, when a communication abnormality occurs between the brake regulating unit and the brake executing unit carried by the vehicle, acquiring a first pressure value of a brake master cylinder at the vehicle.

[0022] In the embodiments of the present application, the brake adjustment unit and the brake execution unit carried by the vehicle generally belong to the modules in the Two-box architecture brake system. Among them, the brake adjustment unit can calculate the required braking force according to the vehicle operation data (for example, brake pedal state data, wheel speed, vehicle body attitude and other data), and realize the brake control of the vehicle by sending accurate brake control instructions to the brake execution unit. The brake execution unit can receive and execute the instructions of the brake adjustment unit, and output the vehicle braking force by pushing the brake master cylinder to control the vehicle to realize braking.

[0023] In the embodiments of the present application, the type of the above-mentioned brake execution unit can be various, for example, can include but not limited to at least one of brake booster and brake-by-wire actuator (BWA). Among them, the brake booster can include intelligent booster, vacuum booster and / or decoupled power brake (DPB). And the brake adjustment unit can include but not limited to electronic stability program (ESP), which can include ESP system suitable for traditional fuel vehicles, or ESP Hev (Hybrid Electronic Stability Program) system specially designed for hybrid (HEV / PHEV) vehicles. This is not limited.

[0024] In the embodiments of the present application, if it is detected that communication abnormality occurs between the brake adjustment unit and the brake execution unit carried by the vehicle, at this time, the brake execution unit may be in a brake function failure state, which causes it to be unable to normally provide brake force assistance; or the brake execution unit may also be in a normal brake function state, so that it can continue to normally provide brake force assistance. Therefore, when the brake execution unit is in different working states, the pressure value of the brake master cylinder at the vehicle will often be different. The brake master cylinder can be used to convert the pedal force applied by the driver into hydraulic pressure to drive the brake to slow down or stop the vehicle, which is not described in detail.

[0025] By acquiring the first pressure value currently possessed by the brake master cylinder of the vehicle when the communication abnormality occurs between the brake adjustment unit and the brake execution unit carried by the vehicle, the working state of the brake execution unit can be conveniently distinguished in combination with the first pressure value, and then the fault detection result for the brake execution unit is accurately generated.

[0026] Step S104, determining a second pressure value that the brake master cylinder should have under the current brake pedal stroke of the vehicle.

[0027] In the embodiments of the present application, if the brake adjusting unit and the brake executing unit carried by the vehicle are both in normal working states, the brake master cylinder of the vehicle generally has consistency in pressure value under the same vehicle operating parameter. The vehicle operating parameter can include a current brake pedal stroke of the vehicle, which can reflect the distance or angle of rotation of the brake pedal from the initial static position (unpressed state) to the current pressed position under the brake pedal pressing operation of the driver. The current brake pedal stroke can generally reflect the braking intention and braking demand of the driver, and the value thereof is often directly related to the braking effect and driving safety.

[0028] In the embodiments of the present application, the pressure value that the brake master cylinder of the vehicle should have under different brake pedal strokes can be obtained by pre-calibration, so that when the communication between the brake adjusting unit and the brake executing unit carried by the vehicle is abnormal, the second pressure value that the brake master cylinder of the vehicle should have under the current brake pedal stroke of the vehicle can be determined according to the pre-calibration data.

[0029] In step S106, a fault detection result for the brake executing unit is generated according to the difference between the first pressure value and the second pressure value.

[0030] In the embodiments of the present application, if the difference between the first pressure value and the second pressure value is large, it generally indicates that the brake executing unit carried by the vehicle cannot normally provide brake force assistance at present, and is in a brake function failure state. If the difference between the first pressure value and the second pressure value is small, it generally indicates that the brake executing unit carried by the vehicle can normally provide brake force assistance at present, and is in a normal brake function state. Thus, the fault detection result for the brake executing unit can be conveniently and accurately generated according to the difference between the first pressure value and the second pressure value.

[0031] Figure 1 The method in the embodiments of the present application can obtain a first pressure value of a brake master cylinder of a vehicle when the communication between a brake adjusting unit and a brake executing unit carried by the vehicle is abnormal, and determine a second pressure value that the brake master cylinder should have under a current brake pedal stroke of the vehicle. By determining the difference between the first pressure value and the second pressure value, an accurate fault detection result for the brake executing unit can be conveniently and quickly generated, which is beneficial to ensuring the safety of the vehicle during operation.

[0032] In some possible implementations, Figure 1 The method in the embodiments of the present application can further include: According to the content of the communication message transmitted between the brake adjustment unit and the brake execution unit, it is determined whether there is a communication abnormality between the brake adjustment unit and the brake execution unit. And / or, According to the communication link state between the brake adjustment unit and the brake execution unit, it is determined whether there is a communication abnormality between the brake adjustment unit and the brake execution unit. And / or, According to the heartbeat packet transmitted between the brake adjustment unit and the brake execution unit based on the heartbeat mechanism, it is determined whether there is a communication abnormality between the brake adjustment unit and the brake execution unit.

[0033] In the embodiments of the present application, the brake adjustment unit and the brake execution unit can generally communicate through the automobile bus (such as CAN bus, LIN bus), SPI interface or other communication link to cooperate to complete the vehicle braking function. In actual application, when there is a communication abnormality between the brake adjustment unit and the brake execution unit, it is possible that one-way communication failure occurs; for example, the brake adjustment unit may not be able to normally send communication data to the brake execution unit, or the brake execution unit may not be able to normally send communication data to the brake adjustment unit; or it is also possible that two-way communication failure occurs between the two, which is not specifically limited.

[0034] In the embodiments of the present application, when identifying whether there is a communication abnormality between the brake adjustment unit and the brake execution unit carried by the vehicle, there can be multiple ways. For example, when a communication abnormality occurs, the content of the communication message transmitted between the brake adjustment unit and the brake execution unit may be missing, abnormal, specific value or transmission delay, etc. Therefore, the communication message transmitted between the brake adjustment unit and the brake execution unit can be combined to accurately identify whether there is a communication abnormality between the two.

[0035] Alternatively, the brake adjustment unit and the brake execution unit generally need to rely on the related communication link when communicating, and if the communication link fails (such as disconnection, poor contact, data accumulation), it will often affect the normal communication process between the brake adjustment unit and the brake execution unit. Therefore, the communication link state between the brake adjustment unit and the brake execution unit can be used to determine whether there is a communication abnormality between the two. In actual application, some communication links have explicit "normal state parameters" (such as CAN bus dominant voltage 2.5-3.5V, recessive voltage 1.5-2.5V), so the voltage, impedance, and whether there is a bus error frame (such as bit error, CRC error) of the communication link can be monitored to improve the discrimination efficiency of whether there is a communication abnormality between the brake adjustment unit and the brake execution unit, which is not specifically limited.

[0036] Alternatively, the heartbeat mechanism is a communication monitoring mechanism between devices, modules or systems, which confirms whether the opposite party is online and the communication link is smooth in real time by periodically sending a lightweight verification signal (heartbeat packet). Based on this, the heartbeat packet transmitted between the brake adjustment unit and the brake execution unit based on the heartbeat mechanism can also be used to timely and efficiently determine whether there is a communication abnormality between the two. In actual application, when the brake adjustment unit or the brake execution unit does not receive the heartbeat packet sent by the opposite party within a specified time, it is determined that there is a communication abnormality between the two. Of course, other strategies can also be used to determine whether there is a communication abnormality between the brake adjustment unit and the brake execution unit based on the transmission of the heartbeat packet, and the specific determination is not limited.

[0037] In some possible implementations, the obtaining of the first pressure value of the brake master cylinder at the vehicle can include: obtaining a pressure value of the brake master cylinder collected by the pressure sensor to obtain the first pressure value.

[0038] In the embodiments of the present application, the vehicle usually carries a pressure sensor to monitor the pressure state in the brake master cylinder in real time, so as to ensure the accuracy of brake control and the safety of vehicle driving. In actual application, the type of the pressure sensor can be various, for example, it can be a piezoresistive pressure sensor or a capacitive pressure sensor, and the specific type is not limited.

[0039] The pressure sensor can usually accurately detect the pressure change in the brake master cylinder and convert the physical pressure into an electrical signal to be transmitted to a related controller (for example, a controller at the brake adjustment unit or the brake execution unit, a domain controller or other vehicle controller carried by the vehicle), so that the related controller can process the electrical signal transmitted by the pressure sensor in real time to determine the current pressure value in the brake master cylinder, thereby serving as the first pressure value required in the step S102, which is convenient and fast and has good accuracy.

[0040] In some possible implementations, the determining of the second pressure value that the brake master cylinder should have under the current brake pedal stroke of the vehicle can include: determining a specified brake master cylinder pressure reference value that has the correlation with the current brake pedal stroke of the vehicle based on the correlation between the brake pedal stroke of the vehicle and the brake master cylinder pressure reference value, to obtain the second pressure value.

[0041] The specified brake master cylinder pressure reference value can be a pressure value that the brake master cylinder can have when the brake adjusting unit and the brake executing unit are in a normal working state and the vehicle is in the current brake pedal stroke.

[0042] In the embodiment of the present application, the pressure value (i.e., the brake master cylinder pressure reference value) that the brake master cylinder should have under different brake pedal strokes can be calibrated in advance when the brake adjusting unit and the brake executing unit are in a normal working state, so as to obtain the correlation between the brake pedal stroke and the brake master cylinder pressure reference value. The brake adjusting unit and the brake executing unit in a normal working state can mean that they can normally communicate with each other, and the brake functions of the two are in a normal state. In actual application, the correlation between the brake pedal stroke and the brake master cylinder pressure reference value can be calibrated by a quasi-static measurement method. Of course, other principles can be used to calibrate the above correlation, which is not limited in particular.

[0043] In the embodiment of the present application, after the current brake pedal stroke of the vehicle is obtained, the specified brake master cylinder pressure reference value that has the above correlation with the current brake pedal stroke can be determined based on the correlation between the brake pedal stroke and the brake master cylinder pressure reference value, so as to be used as the second pressure value that the brake master cylinder of the vehicle should have under the current brake pedal stroke, which is convenient, fast and accurate.

[0044] In some possible embodiments, the correlation can be used to reflect that the brake master cylinder pressure reference value is positively correlated with the brake master cylinder push rod stroke, and the brake master cylinder push rod stroke is positively correlated with the brake pedal stroke.

[0045] In the embodiment of the present application, Figure 2 A structural schematic diagram of a vehicle brake system is provided in the embodiment of the present application. In order to facilitate understanding, the content shown in FIG. 1 is used to illustrate the working principle of the vehicle brake system. Figure 2 In the embodiment of the present application, Figure 2As shown, when the user presses the brake pedal 21, it can move in the direction indicated by curve 22. Furthermore, the brake pedal 21 can be connected to the brake master cylinder push rod 24 via mechanical structures such as linkages and pins. As the driver gradually presses the brake pedal 21, the brake pedal travel can gradually increase, and this can push the linkage to move the brake master cylinder push rod 24, making the brake master cylinder push rod 24 a power source for moving the piston 25 within the brake master cylinder 23. At this time, the pressure value within the brake master cylinder 23 can continuously increase. Conversely, as the driver releases the brake pedal 21, the brake pedal travel can gradually decrease, causing the brake master cylinder push rod travel to also continuously decrease. At this time, the piston 25 within the brake master cylinder 23 can return to its original position via the return spring (…). Figure 2 Under the action of (not shown), it returns to the initial position, thus causing the pressure value in the master cylinder 23 to continuously decrease. Combining the above, it can be seen that the brake pedal travel is positively correlated with the master cylinder push rod travel, and the master cylinder push rod travel is positively correlated with the master cylinder pressure reference value.

[0046] It is understood that the braking system of the vehicle may also include other structures and modules not shown; the brake pedal, brake master cylinder and brake master cylinder push rod and the connection structure between them may also be implemented by other structures, and no specific limitation is made thereto.

[0047] In this embodiment, a first correlation between the brake pedal travel and the brake master cylinder pushrod travel can be predetermined, as can a second correlation between the brake master cylinder pushrod travel and the brake master cylinder pressure reference value. This allows for the determination of an indirect correlation between the brake pedal travel and the brake master cylinder pressure reference value. Alternatively, a direct correlation between the brake pedal travel and the brake master cylinder pressure reference value can be directly determined. This facilitates the determination of the second pressure value that the brake master cylinder should possess under the current brake pedal travel, based on the aforementioned indirect and / or direct correlations. No specific limitations are imposed on this.

[0048] In some feasible implementations, determining a specified brake master cylinder pressure reference value that has the correlation with the current brake pedal travel of the vehicle, based on the correlation between the vehicle's brake pedal travel and the brake master cylinder pressure reference value, may include: Acquire signal data from the pedal travel sensor that reflects the current brake pedal travel of the vehicle.

[0049] Based on the aforementioned correlation and the signal data reflecting the current brake pedal travel, the current brake master cylinder pushrod travel of the vehicle is determined.

[0050] Determine the specified brake master cylinder pressure reference value based on the correlation and the current brake master cylinder push rod stroke.

[0051] In the embodiment of the present application, the pedal stroke sensor can be a sensor carried by the vehicle and capable of converting the mechanical displacement of the driver stepping on the brake pedal into an electronic signal. The pedal stroke sensor can include, but is not limited to, at least one of a pedal angle sensor, a Hall-type pedal stroke sensor, and a potentiometer-type pedal stroke sensor.

[0052] In the embodiment of the present application, when the driver steps on the brake pedal, the brake pedal can generally rotate around a fixed rotating shaft. The deeper the user steps on the brake pedal, the stronger the braking demand, and the greater the rotation angle of the brake pedal, and the greater the corresponding brake pedal stroke. Based on this, the pedal angle sensor can be used to detect the rotation angle of the brake pedal, and the signal data output by the pedal angle sensor can reflect the rotation angle of the brake pedal, so that the signal data can be used to reflect the current brake pedal stroke of the vehicle.

[0053] In actual application, the signal data output by the pedal angle sensor can be a PWM signal (Pulse Width Modulation), and the low / high level time ratio of the PWM signal can be positively correlated with the rotation angle of the brake pedal. If the above correlation can reflect the relationship between the signal data output by the pedal angle sensor and the brake master cylinder push rod stroke of the vehicle, the current brake master cylinder push rod stroke of the vehicle can be determined in combination with the above correlation and the signal data currently collected by the pedal angle sensor for reflecting the current brake pedal stroke of the vehicle.

[0054] In the embodiment of the present application, during the process that the driver steps on or releases the brake pedal, the movement of the brake pedal can change the relative position of the magnet and the Hall-type pedal stroke sensor. At this time, the Hall-type pedal stroke sensor can output a voltage signal capable of reflecting the current brake pedal stroke of the vehicle according to the change of the external magnetic field. If the above correlation can reflect the relationship between the voltage signal output by the Hall-type pedal stroke sensor and the brake master cylinder push rod stroke of the vehicle, the current brake master cylinder push rod stroke of the vehicle can be determined in combination with the above correlation and the voltage signal currently output by the Hall-type pedal stroke sensor.

[0055] In the embodiments of the present application, during the process that the driver steps on or releases the brake pedal, the movement of the brake pedal can change the resistance value of the sliding rheostat at the potentiometric pedal stroke sensor, so that the voltage signal collected by the potentiometric pedal stroke sensor changes. If the above correlation can reflect the relationship between the voltage signal output by the potentiometric pedal stroke sensor and the brake master cylinder push rod stroke of the vehicle, the current brake master cylinder push rod stroke of the vehicle can be determined in combination with the above correlation and the voltage signal currently output by the potentiometric pedal stroke sensor.

[0056] It can be understood that, with the difference of the types of the pedal stroke sensor carried by the vehicle, the specific conversion relationship between the brake pedal stroke and the brake master cylinder push rod stroke reflected by the above correlation can have certain differences, that is, the corresponding formula or characteristic curve used to calculate the current brake master cylinder push rod stroke of the vehicle according to the signal data collected by the pedal stroke sensor to reflect the current brake pedal stroke can have differences, which are not limited specifically.

[0057] In the embodiments of the present application, the above correlation can specifically reflect the characteristic curve between the brake master cylinder push rod stroke of the vehicle and the brake master cylinder pressure reference value, or can also reflect the conversion formula between the brake master cylinder push rod stroke of the vehicle and the brake master cylinder pressure reference value, which is not limited specifically. By substituting the determined current brake master cylinder push rod stroke into the above conversion formula or characteristic curve, the specified brake master cylinder pressure reference value associated with the current brake master cylinder push rod stroke can be conveniently and accurately determined, so that the second pressure value that the brake master cylinder carried by the vehicle should have under the current brake pedal stroke of the vehicle is obtained.

[0058] In actual application, the signal data collected by the pedal stroke sensor in the last several (for example, several to tens of) periods can be filtered, averaged, and processed, to obtain reliable signal data for reflecting the current brake pedal stroke. By performing offset compensation and filtering processing in the process of obtaining the current brake master cylinder push rod stroke of the vehicle in combination with the reliable signal data, it is also beneficial to improve the reliability of the determined current brake master cylinder push rod stroke of the vehicle. Subsequently, the accurate and reliable second pressure value that the brake master cylinder should have can be determined in combination with the current brake master cylinder push rod stroke with good reliability, so as to guarantee the accuracy of the fault detection result generated for the brake execution unit. This is not limited specifically.

[0059] In some possible embodiments, the generating of the fault detection result for the brake execution unit according to the difference between the first pressure value and the second pressure value can include: When the difference between the second pressure value and the first pressure value is greater than a first threshold, a fault detection result is generated to reflect that the braking actuator is in a state of braking function failure. Alternatively, When the difference between the second pressure value and the first pressure value is less than the first threshold, a fault detection result is generated to reflect that the braking actuator is in a normal braking function state.

[0060] In this embodiment, the first threshold can be the minimum pressure reduction in the master cylinder that the braking actuator would cause when the braking function fails compared to when the braking function is normal. In practical applications, the first threshold can be set according to actual needs, for example, from a few bars to tens of bars, without specific limitation.

[0061] In this embodiment, if the difference between the second pressure value that the master cylinder should have under the current brake pedal travel and the first pressure value that the master cylinder actually has reaches a first threshold, it generally indicates that the actual pressure value generated by the master cylinder is too low. In this case, since the braking force assistance generated by the brake actuator is less than the braking force assistance it can generate during normal operation, a fault detection result reflecting that the brake actuator is in a state of brake function failure can be generated. Based on the principle of consistency, if the difference between the second pressure value and the first pressure value is less than the first threshold, it generally indicates that the braking force assistance generated by the brake actuator is consistent with the braking force assistance required during normal operation. Therefore, a fault detection result reflecting that the brake actuator is in a state of normal brake function can be generated.

[0062] In practical applications, when the difference between the second pressure value and the first pressure value is equal to the first threshold, a fault detection result can be generated that reflects the braking actuator being in a state of braking failure, or a fault detection result that reflects the braking actuator being in a state of normal braking function. The result can be set according to actual needs, and no specific limitation is made.

[0063] In some feasible implementations, generating a fault detection result reflecting that the braking actuator is in a braking function failure state when the difference between the second pressure value and the first pressure value is greater than a first threshold may include: If the duration for which the difference between the second pressure value and the first pressure value is greater than the first threshold reaches the second threshold, a fault detection result is generated to reflect that the braking actuator is in a state of braking function failure.

[0064] In the embodiments of the present application, the second threshold value can be a minimum duration required for the difference between the second pressure value and the first pressure value to be greater than the first threshold value when determining that the brake execution unit is in the brake function failure state. In actual applications, the second threshold value can be set according to actual needs, for example, it can be hundreds of milliseconds to several seconds, which is not limited specifically.

[0065] By allowing the fault detection result for reflecting that the brake execution unit is in the brake function failure state to be generated only when the duration that the difference between the second pressure value and the first pressure value is greater than the first threshold value reaches the second threshold value, it is beneficial to avoid incorrectly determining that the brake execution unit is in the brake function failure state due to calculation errors, noise and other factors, thereby improving the accuracy of the fault detection result generated for the brake execution unit.

[0066] In actual applications, if the difference between the second pressure value and the first pressure value is greater than the first threshold value, but the duration does not reach the second threshold value, the fault detection result for reflecting that the brake execution unit is in the normal brake function state can be generated, or the fault detection result for the brake execution unit can not be generated temporarily, which is good in flexibility and is beneficial to ensure the reliability of the generated fault detection result.

[0067] In actual applications, when the brake execution unit is in the brake function failure state, it can completely fail to generate brake force assistance, or it can only be able to generate a brake force assistance with a small value. Based on this, the difference between the first pressure value and the second pressure value can also be used to generate a fault detection result that can reflect that the brake execution unit is in a complete brake function failure state, or a fault detection result that can reflect that the brake execution unit is in a partial brake function failure state. This is beneficial to ensure the fineness and accuracy of the generated fault detection result, which is not limited specifically.

[0068] In some possible implementations, after the fault detection result for reflecting that the brake execution unit is in the brake function failure state is generated, the method can further include: generating an emergency brake control instruction for the vehicle based on a current brake pedal stroke of the vehicle, wherein the emergency brake control instruction indicates a brake force that is positively correlated with the current brake pedal stroke. Or, sending the fault detection result for reflecting that the brake execution unit is in the brake function failure state to a specified controller, wherein the specified controller is configured to generate an emergency brake control instruction for the vehicle based on the fault detection result.

[0069] In the embodiments of the present application, if Figure 1 If the fault detection result generated in the embodiments and examples thereof reflects that the brake execution unit is in the brake function failure state, the brake force assistance can beFigure 1 The execution subject of the method or a designated controller generates an emergency braking control instruction for the vehicle to quickly control the vehicle to stop, thereby reducing the risk during the driving of the vehicle and protecting the safety and experience of the driver and passengers.

[0070] In actual applications, since a larger current brake pedal stroke of the vehicle can generally reflect a more urgent demand of the driver for quickly stopping the vehicle, the brake force indicated by the emergency braking control instruction can be positively correlated with the current brake pedal stroke of the vehicle, thereby protecting the driving intention of the user and protecting the safety of the driver and passengers. Of course, the emergency braking control instruction for the vehicle can also be generated in combination with the surrounding environment data of the vehicle and other related vehicle operating parameters, which is not specifically limited.

[0071] The above fault detection scheme provided by the present application can accurately identify whether the brake execution unit is in a brake function failure state when the communication between the brake adjustment unit and the brake execution unit of the vehicle is abnormal, and if so, the vehicle can be controlled to perform emergency braking to protect the safety of the driver and passengers, and if not, the brake adjustment unit can normally perform brake control to avoid the problems of excessive braking or insufficient braking performance, which is also beneficial to protect the safety and experience of the driver and passengers. In the implementation of the above scheme, the hardware configuration of the vehicle is generally not required to be changed, the implementation cost is low, and the practicability is good.

[0072] The present application also provides a computer program product, which can contain a computer program that can implement the steps of the fault detection method provided by at least some of the above embodiments when executed, and the specific execution process can be referred to the specific description in the above embodiments, which is not described here.

[0073] The present application also provides a storage medium, which can store a computer program that can implement the fault detection method provided by at least some of the above embodiments when executed, and the specific execution process can be referred to the specific description in the above embodiments, which is not described here.

[0074] The present application also provides Figure 3 The structure of the vehicle controller is shown in the figure. As shown in the figure Figure 3 On the hardware level, the vehicle controller can include a processor 31 and a memory 35, and can also include an internal bus 32, a network interface 33, a memory 34, and other hardware required by the business. The vehicle controller can be arranged in the vehicle, and the processor 31 in the vehicle controller can read the corresponding computer program from the memory 35 into the memory and then run to implement the above fault detection method, and the specific execution process can be referred to the specific description in the above embodiments, which is not described here.

[0075] In some possible embodiments, the vehicle controller can include at least one of an Electronic Control Unit (ECU) of a brake adjustment unit at the vehicle and a domain controller mounted at the vehicle. Of course, the vehicle controller can also be other controllers mounted at the vehicle, which are not specifically limited.

[0076] The application also provides a vehicle, which can include a brake adjustment unit, a brake execution unit, and the vehicle controller described above to execute the steps of the fault detection method of at least some of the embodiments described above. The specific execution process can be referred to the specific description in the embodiments described above, which is not described here.

[0077] In some possible embodiments, the vehicle can also include other vehicle systems or other vehicle controllers, which are not specifically limited.

[0078] Finally, each of the embodiments in the application is described in a progressive manner, and the same and similar parts between the embodiments can be referred to each other. Each embodiment focuses on the difference from other embodiments. In particular, the computer program product, the storage medium, the vehicle controller, and the vehicle are basically similar to the method embodiments, and therefore the description is relatively simple. The relevant parts can be referred to the part of the method embodiments.

[0079] The above only describes the embodiments of the application and is not intended to limit the application. The application can have various changes and modifications for those skilled in the art. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the application shall be included in the scope of the claims of the application.

Claims

1. A fault detection method, comprising: When communication between the brake adjustment unit and the brake execution unit installed in the vehicle is abnormal, the first pressure value of the brake master cylinder at the vehicle is obtained; Determine a second pressure value that the master cylinder should have under the current brake pedal travel of the vehicle; Based on the difference between the first pressure value and the second pressure value, a fault detection result is generated for the braking actuator.

2. The method according to claim 1, further comprising: Based on the communication message content transmitted between the brake adjustment unit and the brake execution unit, determine whether there is a communication anomaly between the brake adjustment unit and the brake execution unit; and / or, Based on the communication link status between the brake adjustment unit and the brake execution unit, determine whether there is a communication anomaly between the brake adjustment unit and the brake execution unit; and / or, Based on the heartbeat packets transmitted between the braking adjustment unit and the braking execution unit using a heartbeat mechanism, it is determined whether there is a communication anomaly between the braking adjustment unit and the braking execution unit.

3. The method according to claim 1, wherein obtaining the first pressure value of the brake master cylinder at the vehicle comprises: The pressure value inside the brake master cylinder is obtained from the pressure sensor to obtain the first pressure value.

4. The method according to claim 1, wherein determining the second pressure value that the brake master cylinder should have under the current brake pedal travel of the vehicle comprises: Based on the correlation between the vehicle's brake pedal travel and the brake master cylinder pressure reference value, a specified brake master cylinder pressure reference value that has the correlation with the vehicle's current brake pedal travel is determined, and the second pressure value is obtained. The specified brake master cylinder pressure reference value is the pressure value that the vehicle can achieve in the brake master cylinder under the current brake pedal stroke when both the brake adjustment unit and the brake execution unit are in normal working condition.

5. The method according to claim 4, wherein the correlation is used to reflect a positive correlation between the brake master cylinder pressure reference value and the brake master cylinder push rod stroke, and a positive correlation between the brake master cylinder push rod stroke and the brake pedal stroke.

6. The method according to claim 5, wherein determining a specified brake master cylinder pressure reference value having the correlation with the current brake pedal travel of the vehicle based on the correlation between the brake pedal travel of the vehicle and the brake master cylinder pressure reference value comprises: Acquire signal data from the pedal travel sensor that reflects the current brake pedal travel of the vehicle; Based on the aforementioned correlation and the signal data used to reflect the current brake pedal travel, the current brake master cylinder pushrod travel of the vehicle is determined; Based on the aforementioned correlation and the current brake master cylinder push rod stroke, the specified brake master cylinder pressure reference value is determined.

7. The method according to claim 6, wherein the pedal travel sensor comprises: At least one of a pedal angle sensor, a Hall effect pedal travel sensor, and a potentiometer-type pedal travel sensor.

8. The method according to claim 1, wherein generating a fault detection result for the braking actuator based on the difference between the first pressure value and the second pressure value includes: When the difference between the second pressure value and the first pressure value is greater than the first threshold, a fault detection result is generated to reflect that the braking actuator is in a state of braking function failure. or, When the difference between the second pressure value and the first pressure value is less than the first threshold, a fault detection result is generated to reflect that the braking actuator is in a normal braking function state.

9. The method according to claim 8, wherein generating a fault detection result reflecting that the braking actuator is in a braking function failure state when the difference between the second pressure value and the first pressure value is greater than a first threshold includes: If the duration for which the difference between the second pressure value and the first pressure value is greater than the first threshold reaches the second threshold, a fault detection result is generated to reflect that the braking actuator is in a state of braking function failure.

10. The method according to claim 8, further comprising, after generating a fault detection result reflecting that the braking actuator is in a braking function failure state: Based on the current brake pedal travel of the vehicle, an emergency braking control command is generated for the vehicle; wherein the braking force indicated by the emergency braking control command is positively correlated with the current brake pedal travel; or... A fault detection result reflecting that the braking actuator is in a braking failure state is sent to a designated controller; the designated controller is used to generate an emergency braking control command for the vehicle based on the fault detection result.

11. The method according to any one of claims 1-10, wherein the braking actuation unit comprises: At least one of a brake booster and a hydraulic brake-by-wire system; The braking adjustment unit includes: electronic stability control system.

12. A computer program product comprising a computer program that, when executed, performs the steps of the method according to any one of claims 1 to 11.

13. A storage medium having a computer program stored thereon, wherein the computer program, when executed, performs the steps of the method according to any one of claims 1 to 11.

14. A vehicle controller, comprising: A processor and a memory; wherein the memory stores a computer program adapted to be loaded by the processor and to execute the steps of the method as claimed in any one of claims 1 to 11.

15. The vehicle controller of claim 14, wherein the vehicle controller comprises: The braking actuator in the vehicle has at least one of an electronic control unit and a domain controller mounted in the vehicle.

16. A vehicle comprising: Braking adjustment unit, braking actuation unit, and vehicle controller as described in claim 14.

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