An EHB pressure sensor redundancy control method and system

Abstract

This invention relates to an EHB pressure sensor redundancy control method and system, belonging to the field of automotive technology. The method includes: real-time acquisition of dual-channel physical signals within the same cycle; obtaining the piston displacement value of the piston inside the pressure-building cylinder based on the motor rotor angle signal and the mechanical transmission ratio; performing fault detection on the pressure sensor based on a preset cycle; determining an estimated displacement pressure value when the pressure sensor is found to be normal, and determining a first target deviation value based on the vehicle status signal indicating that steady-state braking conditions are met, and updating the first target deviation value to the displacement range corresponding to the piston displacement value; obtaining a target estimated pressure value when the pressure sensor is found to be abnormal, and performing closed-loop braking adjustment of the drive motor based on the target estimated pressure value. This method achieves a stable continuation of braking pressure after failure, avoiding the safety effect of a sudden drop in braking force and a surge in braking distance caused by traditional mechanical backup modes.

Description

Technical Field

[0001] This invention belongs to the field of automotive technology, and in particular relates to an EHB pressure sensor redundancy control method and system. Background Technology

[0002] In related technologies, the core closed-loop control of the EHB (Electro-Hydraulic Braking) brake-by-wire system relies on real-time pressure signals fed back by the pressure sensor of the pressure build-up cylinder to achieve precise adjustment of braking force. When the pressure sensor fails due to short circuit, open circuit, signal drift, or self-test failure, the EHB instantly switches to mechanical backup braking mode. The brake assist function is lost, and braking relies solely on hydraulic pressure generated by the driver pressing the brake pedal. This significantly reduces braking deceleration, greatly increasing braking distance for high-speed vehicles and potentially causing collisions and other driving safety hazards. Therefore, how to better achieve redundant control of the EHB pressure sensor has become an urgent problem to be solved. Summary of the Invention

[0003] In view of the shortcomings of the prior art, the purpose of the invention is to provide an EHB pressure sensor redundancy control method and system.

[0004] In a first aspect, the present invention proposes an EHB pressure sensor redundancy control method, comprising: S1, real-time acquisition of dual physical signals within the same period, wherein the dual physical signals include a braking pressure signal fed back by a pressure sensor and a motor rotor angle signal fed back by a motor position sensor; S2, obtaining the piston displacement value of the piston inside the pressure-building cylinder based on the motor rotor angle signal and the mechanical transmission ratio; S3, performing fault detection on the pressure sensor based on a preset period, and determining an estimated displacement pressure value based on the piston displacement value and the pressure mapping relationship when the pressure sensor is determined to be normal, and determining a first target deviation value based on the braking pressure value fed back by the pressure sensor and the estimated displacement pressure value when the vehicle status signal determines that steady-state braking conditions are met, and updating the first target deviation value to the displacement interval corresponding to the piston displacement value; S4, determining a second target deviation value based on the displacement interval corresponding to the piston displacement value when the pressure sensor is determined to be abnormal, superimposing and compensating the second target deviation value and the estimated displacement pressure value to obtain a target estimated pressure value, and performing closed-loop braking adjustment of the drive motor based on the target estimated pressure value.

[0005] A second aspect of the present invention provides an EHB pressure sensor redundancy control system, comprising: an acquisition module for real-time acquisition of dual physical signals within the same period, wherein the dual physical signals include a braking pressure signal fed back by a pressure sensor and a motor rotor angle signal fed back by a motor position sensor; an acquisition module for obtaining the piston displacement value of the piston inside the pressure-building cylinder based on the motor rotor angle signal and the mechanical transmission ratio; an update module for fault detection of the pressure sensor based on a preset period, determining an estimated displacement pressure value based on the piston displacement value and the pressure mapping relationship when the pressure sensor is determined to be in a normal state, and determining a first target deviation value based on the braking pressure value fed back by the pressure sensor and the estimated displacement pressure value when the vehicle status signal determines that steady-state braking conditions are met, and updating the first target deviation value to the displacement range corresponding to the piston displacement value; and an execution module for determining a second target deviation value based on the displacement range corresponding to the piston displacement value when the pressure sensor is determined to be in a normal state, superimposing and compensating the second target deviation value and the estimated displacement pressure value to obtain a target estimated pressure value, and executing closed-loop braking adjustment of the drive motor based on the target estimated pressure value.

[0006] A third aspect of the present invention provides an electronic device comprising: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor to enable the at least one processor to perform the method described in any one aspect of the present invention.

[0007] A fourth aspect of the present invention provides a non-transitory computer-readable storage medium storing computer instructions, wherein the computer instructions are used to cause the computer to perform the method described in any one of the first aspects of the present invention.

[0008] The beneficial effects of this invention are as follows: The EHB pressure sensor redundancy control method and system of this invention acquires dual physical signals in real time within the same cycle. These dual physical signals include a braking pressure signal fed back by the pressure sensor and a motor rotor angle signal fed back by the motor position sensor. Based on the motor rotor angle signal and the mechanical transmission ratio, the piston displacement value inside the pressure-building cylinder is obtained. Fault detection of the pressure sensor is performed based on a preset cycle. If the pressure sensor is determined to be normal, an estimated displacement pressure value is determined based on the mapping relationship between the piston displacement value and the pressure. If the vehicle status signal indicates that steady-state braking conditions are met, a first target deviation value is determined based on the braking pressure value fed back by the pressure sensor and the estimated displacement pressure value. This first target deviation value is then updated to the displacement range corresponding to the piston displacement value. If the pressure sensor is determined to be abnormal, a second target deviation value is determined based on the displacement range corresponding to the piston displacement value. The second target deviation value and the estimated displacement pressure value are superimposed and compensated to obtain a target estimated pressure value. Closed-loop braking adjustment of the drive motor is then performed based on this target estimated pressure value. This method learns and stores steady-state deviations when the pressure sensor is working properly, and calls these deviations to compensate for displacement and estimate pressure when the pressure sensor fails, thereby maintaining closed-loop braking control of the motor. This achieves a safe effect of smooth braking pressure continuity after failure and avoids the sudden drop in braking force and surge in braking distance caused by traditional mechanical backup mode. Attached Figure Description

[0009] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts. It is obvious that the drawings described below are merely some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings.

[0010] Figure 1 This is a flowchart of an EHB pressure sensor redundancy control method according to an embodiment of the present invention; Figure 2 This is a flowchart of an EHB pressure sensor redundancy control method according to a specific embodiment of the present invention; Figure 3 This is a structural block diagram of the EHB pressure sensor redundancy control system according to an embodiment of the present invention; Figure 4 This is a structural block diagram of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0011] To enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. It should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0012] Furthermore, descriptions of well-known structures and techniques are omitted in the following description to avoid unnecessarily obscuring the concepts disclosed in this invention.

[0013] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "installed," "connected," and "linked" should be interpreted broadly; for example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0014] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of methods and systems consistent with some aspects of the invention as detailed in the appended claims.

[0015] This invention proposes an EHB pressure sensor redundancy control method, system, and related equipment. Specifically, the EHB pressure sensor redundancy control method, system, and related equipment of this invention are described below with reference to the accompanying drawings.

[0016] Figure 1This is a flowchart of an EHB pressure sensor redundancy control method according to an embodiment of the present invention. It should be noted that the EHB pressure sensor redundancy control method of this embodiment can be applied to the EHB pressure sensor redundancy control system of this embodiment. This EHB pressure sensor redundancy control system can be configured on an electronic device or in a server. This application does not limit the scope of the application.

[0017] like Figure 1 As shown, the EHB pressure sensor redundancy control method includes: S110 acquires dual physical signals in real time within the same cycle. The dual physical signals include the braking pressure signal fed back by the pressure sensor and the motor rotor angle signal fed back by the motor position sensor.

[0018] In embodiments of the present invention, dual physical signals can be acquired in real time within the same cycle based on a signal acquisition interface. Specifically, the signal acquisition interface acquires a braking pressure signal in real time via a pressure sensor; this signal is either an analog voltage or a digital signal, representing the real-time hydraulic pressure within the pressure-building cylinder. The signal acquisition interface also acquires a motor rotor angle signal in real time via a motor position sensor.

[0019] The motor position sensor is preferably a rotary transformer or a magneto-electric encoder to ensure accurate measurement of the rotor position.

[0020] S120: Based on the motor rotor angle signal and the mechanical transmission ratio, the piston displacement value of the piston inside the pressure-building cylinder is obtained.

[0021] In embodiments of the present invention, the motor rotor angle value can be determined based on the motor rotor angle signal; the lead parameter of the lead screw assembly can be obtained, which is the linear stroke generated by the nut and piston driven by the lead screw assembly rotating one revolution; the reduction ratio of the reduction mechanism set between the motor output shaft and the lead screw assembly can be obtained, which is the ratio of the number of rotations of the motor to the number of rotations of the lead screw assembly; the piston displacement value of the piston inside the pressure building cylinder can be obtained based on x = (θ / (i × 360°)) × L, where x represents the piston displacement value, θ represents the motor rotor angle value, i represents the reduction ratio, and L represents the lead parameter.

[0022] In other words, the rotor angle signal of the motor based on the feedback from the motor position sensor is first decoded to obtain the rotor angle value θ at the current moment. This angle value is in degrees and is a value between 0° and 360° or a cumulative angle value over multiple revolutions. Then, the mechanical structure parameters of the system stored in its internal memory are called, including: (1) the lead parameter L of the lead screw assembly 120, which is defined as the linear stroke generated by the nut and the piston fixed to the nut when the lead screw rotates one revolution (i.e., 360°), and the unit is usually millimeters (mm); (2) the reduction ratio i of the reduction mechanism set between the output shaft of the drive motor and the lead screw assembly, which is defined as the ratio of the number of revolutions of the drive motor to the number of revolutions of the lead screw assembly (i.e., the motor rotates i revolutions and the lead screw rotates 1 revolution). Finally, the piston displacement value is calculated based on the formula x = (θ / (i × 360°)) × L.

[0023] For example, when the reduction ratio i is 4, the lead L is 2mm, and the motor rotor angle θ is 1440°, the number of rotations of the lead screw is 1440 / (4×360)=1 rotation, and the piston displacement x=1×2=2mm.

[0024] S130, based on a preset cycle, fault detection is performed on the pressure sensor. If the pressure sensor is determined to be in a normal state, the displacement estimated pressure value is determined based on the piston displacement value and the pressure mapping relationship. If the steady-state braking conditions are met by judging from the vehicle status signal, the first target deviation value is determined based on the braking pressure value fed back by the pressure sensor and the displacement estimated pressure value, and the first target deviation value is updated to the displacement range corresponding to the piston displacement value.

[0025] In an embodiment of the present invention, when the piston displacement value of the piston inside the pressure-building cylinder is obtained, a fault detection of the pressure sensor is performed based on a preset period. If the pressure sensor is determined to be in normal condition, a steady-state deviation self-learning and update operation is performed. This ensures that in the event of a pressure sensor failure, the pre-learned deviation value within the specified interval can be called based on the real-time displacement to accurately compensate for the estimated pressure, thereby ensuring the accuracy of pressure estimation and braking smoothness after failure. Specifically, based on the piston displacement value and the pressure mapping relationship, the displacement-estimated pressure value is determined. Furthermore, if the vehicle status signal indicates that steady-state braking conditions are met, a first target deviation value is determined based on the braking pressure value fed back by the pressure sensor and the displacement-estimated pressure value. This first target deviation value is then updated to the displacement interval corresponding to the piston displacement value. Specific implementation details can be found in subsequent embodiments.

[0026] S140, if the pressure sensor is determined to be in an abnormal state, a second target deviation value is determined based on the displacement range corresponding to the piston displacement value. The second target deviation value and the displacement estimated pressure value are superimposed and compensated to obtain the target estimated pressure value. The closed-loop braking adjustment of the drive motor is then performed based on the target estimated pressure value.

[0027] In an embodiment of the present invention, when the pressure sensor is determined to be abnormal, a triggered redundant estimation and degraded braking control operation is executed to achieve smooth and controllable power output in the absence of a sensor, until the vehicle comes to a safe stop or the pressure sensor malfunction is resolved. Specifically, a second target deviation value is determined based on the displacement range corresponding to the piston displacement value. The second target deviation value and the displacement-estimated pressure value are superimposed and compensated to obtain a target estimated pressure value. Closed-loop braking adjustment of the drive motor is then performed based on the target estimated pressure value. Specific implementation details can be found in subsequent embodiments.

[0028] According to the EHB pressure sensor redundancy control method of the present invention, dual physical signals are acquired in real time within the same cycle. The dual physical signals include the braking pressure signal fed back by the pressure sensor and the motor rotor angle signal fed back by the motor position sensor. The piston displacement value of the piston inside the pressure-building cylinder is obtained based on the motor rotor angle signal and the mechanical transmission ratio. The pressure sensor is fault-detected based on a preset cycle. If the pressure sensor is determined to be in a normal state, an estimated displacement pressure value is determined based on the mapping relationship between the piston displacement value and the pressure. If the steady-state braking condition is met based on the vehicle status signal, a first target deviation value is determined based on the braking pressure value fed back by the pressure sensor and the estimated displacement pressure value. The first target deviation value is then updated to the displacement range corresponding to the piston displacement value. If the pressure sensor is determined to be in a faulty state, a second target deviation value is determined based on the displacement range corresponding to the piston displacement value. The second target deviation value and the estimated displacement pressure value are superimposed and compensated to obtain a target estimated pressure value. Closed-loop braking adjustment of the drive motor is then performed based on the target estimated pressure value. This method learns and stores steady-state deviations when the pressure sensor is working properly, and calls these deviations to compensate for displacement and estimate pressure when the pressure sensor fails, thereby maintaining closed-loop braking control of the motor. This achieves a safe effect of smooth braking pressure continuity after failure and avoids the sudden drop in braking force and surge in braking distance caused by traditional mechanical backup mode.

[0029] To enable those skilled in the art to more readily understand the present invention, Figure 2 This is an EHB pressure sensor redundancy control method according to a specific embodiment of the present invention, such as... Figure 2 As shown, the EHB pressure sensor redundancy control method includes: S210 acquires dual physical signals in real time within the same cycle. The dual physical signals include the braking pressure signal fed back by the pressure sensor and the motor rotor angle signal fed back by the motor position sensor.

[0030] S220: Based on the motor rotor angle signal and the mechanical transmission ratio, the piston displacement value of the piston inside the pressure-building cylinder is obtained.

[0031] In the embodiments of the present invention, the implementation of steps S210-S220 can refer to the implementation of steps S110-S120 described above, and the present invention will not repeat the details.

[0032] S230 performs fault detection on the pressure sensor based on a preset cycle to determine whether the pressure sensor is in a state of no abnormality.

[0033] In an embodiment of the present invention, based on a preset period, it is detected whether the amplitude of the braking pressure signal exceeds a preset upper or lower limit; based on a preset period, it is detected whether the rate of change of the braking pressure signal exceeds a preset change threshold; based on a preset period, it is detected whether the internal self-test state of the pressure sensor passes.

[0034] The pressure sensor integrates a self-test circuit that performs periodic internal diagnostics. The self-test status flag of the pressure sensor is read via a communication interface (e.g., PSI5 (Peripheral Sensor Interface 5) or SPI (Serial Peripheral Interface)). If this flag indicates a self-test failure, the pressure sensor is determined to have an internal fault.

[0035] S240, if the pressure sensor is determined to be in normal condition, the displacement estimated pressure value is determined based on the piston displacement value and pressure mapping relationship. If the steady-state braking conditions are met by judging from the vehicle status signal, the first target deviation value is determined based on the braking pressure value fed back by the pressure sensor and the displacement estimated pressure value, and the first target deviation value is updated to the displacement range corresponding to the piston displacement value.

[0036] In an embodiment of the present invention, the pressure sensor is determined to be in a normal state if the amplitude of the braking pressure signal does not exceed the preset upper and lower limits, the rate of change of the braking pressure signal does not exceed the preset change threshold, and the internal self-test of the pressure sensor passes. That is, the pressure sensor is determined to be in a normal state only if all three conditions are met simultaneously.

[0037] In an embodiment of the present invention, the piston displacement value and pressure mapping relationship can be preset. When the piston displacement value is obtained, the piston displacement value and pressure mapping relationship is called based on the piston displacement value to obtain the pressure value corresponding to the piston displacement value, that is, the displacement estimated pressure value.

[0038] For example, in bench tests, high-precision pressure sensors are used as references to record the actual braking pressure data corresponding to different piston displacements. Piecewise linear interpolation or least-squares polynomial fitting methods are then used to establish a static displacement-pressure mapping table or fitting function, i.e., the mapping relationship between piston displacement values ​​and pressure.

[0039] In an embodiment of the present invention, the ABS state is obtained based on the anti-lock braking system ABS and the ESC state is obtained based on the electronic stability control system ESC; if it is determined that both the ABS state and the ESC state are inactive, it is determined that the steady-state braking condition is met.

[0040] In other words, the vehicle's CAN bus or FlexRay bus acquires vehicle status signals, specifically the ABS_Active activation signal and the ESC_Active activation signal. By monitoring these two signals, the vehicle is determined to be in steady-state braking only when both ABS_Active and ESC_Active are simultaneously 0 (i.e., not activated). By determining that the vehicle is in steady-state braking, the collected pressure signals are ensured to represent the steady-state pressure under the driver's intended steady braking, eliminating pressure fluctuation interference caused by dynamic adjustments of ABS or ESC.

[0041] In an embodiment of the present invention, the difference between the braking pressure value and the displacement estimation pressure value is calculated, and the difference is used as the first target deviation value.

[0042] In embodiments of the present invention, after calculating a first target deviation value, the first target deviation value is categorized according to the displacement interval corresponding to the piston displacement value and stored in a non-volatile memory (e.g., EEPROM (Electrically Erasable Programmable Read-Only Memory) or Flash memory). For the same displacement interval, after each new deviation value is calculated, the deviation value stored in that interval is updated to ensure that the stored deviation value is the one learned under the latest steady-state conditions. This deviation value is used to compensate for inherent system errors (including mechanical manufacturing tolerances, sensor zero-point drift, friction, etc.) and wear or aging deviations caused by long-term use.

[0043] S250, when it is determined that the pressure sensor is in an abnormal state, determines a second target deviation value based on the displacement range corresponding to the piston displacement value, superimposes the second target deviation value and the displacement estimated pressure value to obtain the target estimated pressure value, and performs closed-loop braking adjustment of the drive motor based on the target estimated pressure value.

[0044] In an embodiment of the present invention, the pressure sensor is determined to be abnormal if the amplitude of the braking pressure signal exceeds a preset upper or lower limit and / or the rate of change of the braking pressure signal exceeds a preset change threshold and / or the internal self-test of the pressure sensor fails. That is, if any of these conditions are not met, the pressure sensor is determined to be abnormal.

[0045] In an embodiment of the present invention, the latest stored deviation value within the corresponding displacement interval is retrieved based on the piston displacement value, and this deviation value is used as the second target deviation value. That is, based on the displacement interval corresponding to the piston displacement value, the latest stored deviation value for that displacement interval is read from the non-volatile memory and used as the second target deviation value.

[0046] In an embodiment of the present invention, the sum of the second target deviation value and the displacement estimated pressure value is calculated, and the sum is used as the target estimated pressure value. That is, the second target deviation value and the displacement estimated pressure value are superimposed and compensated to obtain the target estimated pressure value, which serves as the pressure feedback amount during the failure period.

[0047] In an embodiment of the present invention, when a target estimated pressure value is obtained, the target estimated pressure value is subjected to rate of change limiting processing based on the target estimated pressure value; the limited estimated pressure value is used as a feedback quantity to maintain the closed-loop braking adjustment of the drive motor until the vehicle comes to a safe stop or the abnormal state of the pressure sensor disappears.

[0048] Specifically, the pressure change rate is determined based on the target estimated pressure value of the current period and the target estimated pressure value of the previous period. If the pressure change rate exceeds the preset pressure change rate, the output is increased or decreased according to the preset pressure change rate. If the pressure change rate does not exceed the preset pressure change rate, the target estimated pressure value is used as the feedback quantity.

[0049] In other words, to ensure the smoothness of the pressure feedback value and avoid sudden changes in braking force due to jumps in estimated pressure, the target estimated pressure value is subject to rate-of-change limiting. Specifically, in the current cycle, the target estimated pressure value of the previous cycle is read, the difference between the current cycle and the previous cycle is calculated, and then divided by the cycle duration to obtain the current pressure change rate. This change rate is then compared with a preset pressure change rate (e.g., 10 MPa / s, which can be calibrated based on actual vehicle settings). If the calculated change rate exceeds the preset pressure change rate, the output is incremented or decremented from the estimated pressure value of the previous cycle towards the estimated pressure value of the current cycle at the preset pressure change rate, i.e., the slope of the output value is limited. If the calculated change rate does not exceed the preset pressure change rate, the target estimated pressure value is directly used as the feedback quantity.

[0050] Furthermore, the estimated pressure value after limiting is used as the pressure feedback quantity to maintain the PID (Proportional-Integral-Derivative) closed-loop braking control of the drive motor. Specifically, the motor drive current command can be calculated based on the deviation between the target braking pressure and the feedback quantity, and output to the drive motor through the drive circuit to adjust the piston's thrust displacement, thereby achieving smooth and controllable degraded braking until the vehicle comes to a safe stop or the abnormal state of the pressure sensor disappears.

[0051] In one embodiment of the present invention, the pressure sensor signal can be continuously monitored during the period when the pressure sensor is in an abnormal state. The condition for restoring normal operation is as follows: with a judgment period of 5ms, when the amplitude, rate of change, and self-test status of the pressure sensor are all detected to be normal for 5 consecutive periods (i.e., 25ms), it is determined that the pressure sensor has returned to normal, and the system automatically switches back to the conventional pressure closed-loop control mode, that is, the actual pressure value fed back by the pressure sensor is used as the closed-loop feedback quantity again.

[0052] In one embodiment of the present invention, the EHB pressure sensor redundancy control method can be applied to an EHB pressure sensor redundancy control system, which mainly includes: a brake pedal, a pressure-building cylinder, a piston, a lead screw assembly, a drive motor, a motor position sensor, a pressure sensor, and an electronic control unit (ECU). The pressure-building cylinder contains a piston, which is mechanically connected to the nut of the lead screw assembly. The lead screw of the lead screw assembly is driven by the output shaft of the drive motor through a reduction mechanism. The pressure sensor is located on the hydraulic output oil circuit of the pressure-building cylinder to provide real-time feedback of the brake pressure signal. The motor position sensor is located at the rotor end of the drive motor to provide real-time feedback of the motor rotor angle signal. The ECU is communicatively connected to the pressure sensor, the motor position sensor, and the drive motor to receive signals and output control commands.

[0053] According to the EHB pressure sensor redundancy control method of this invention, when the sensor malfunctions, it can seamlessly switch to redundancy estimation mode, using the motor position signal to calculate a reliable pressure feedback value and maintain closed-loop braking control of the motor. This allows the vehicle to achieve smooth and controllable degraded braking until it comes to a safe stop even after sensor failure, significantly shortening the braking distance at high speeds and reducing the risk of collision. When the sensor is working normally, it continuously learns and stores the steady-state deviation between the "actual pressure and estimated pressure" under different piston displacement ranges. When the sensor fails, the system calls upon the historical learning deviation of the corresponding range to superimpose compensation on the estimated pressure. This mechanism effectively compensates for systematic deviations such as mechanical manufacturing tolerances, sensor zero-point drift, friction, and long-term wear, significantly improving the absolute accuracy of pressure estimation under failure conditions; the rate of change of the final output target estimated pressure value is limited. When the calculated pressure change rate exceeds the preset pressure change rate, the system increases or decreases the output according to the preset pressure change rate, effectively preventing sudden changes in braking force caused by signal jumps or estimation disturbances, avoiding vehicle jerking, and ensuring smooth vehicle operation and driver comfort during degraded braking. By setting clear fault judgment conditions (amplitude, change rate, self-test status) and recovery judgment conditions (normal signal for 5 consecutive cycles), on the one hand, seamless switching from normal mode to redundant mode is achieved; on the other hand, after the sensor fault is cleared, it can automatically switch back to conventional pressure closed-loop control without manual intervention, improving the system's intelligence and availability. This method, through a hardware and software collaborative redundant control strategy, enables the EHB brake-by-wire system to maintain high braking performance and stability even when facing the failure of the pressure sensor, a critical component, reducing the probability of vehicle collisions and other driving safety accidents caused by sensor failure, and improving the functional safety level of the entire braking system.

[0054] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods according to the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods of the various embodiments of this application.

[0055] According to one aspect of the present invention, an EHB pressure sensor redundancy control system is also proposed. Figure 3 This is a schematic diagram of the EHB pressure sensor redundancy control system according to an embodiment of the present invention; as shown. Figure 3 As shown, it includes: The acquisition module 310 is used to acquire dual physical signals in real time within the same cycle, wherein the dual physical signals include the braking pressure signal fed back by the pressure sensor and the motor rotor angle signal fed back by the motor position sensor. The module 320 is used to obtain the piston displacement value of the piston inside the pressure-building cylinder based on the motor rotor angle signal and the mechanical transmission ratio. The update module 330 is used to perform fault detection on the pressure sensor based on a preset period. When it is determined that the pressure sensor is in a normal state, it determines the displacement estimated pressure value based on the piston displacement value and the pressure mapping relationship. When it is determined by the vehicle status signal that the steady-state braking conditions are met, it determines the first target deviation value based on the braking pressure value fed back by the pressure sensor and the displacement estimated pressure value, and updates the first target deviation value to the displacement range corresponding to the piston displacement value. The execution module 340 is used to determine a second target deviation value based on the displacement range corresponding to the piston displacement value when the state of the pressure sensor is determined to be abnormal, to superimpose the second target deviation value and the displacement estimated pressure value to obtain a target estimated pressure value, and to perform closed-loop braking adjustment of the drive motor based on the target estimated pressure value.

[0056] According to an embodiment of the EHB pressure sensor redundancy control system of the present invention, dual physical signals are acquired in real time within the same cycle. The dual physical signals include the braking pressure signal fed back by the pressure sensor and the motor rotor angle signal fed back by the motor position sensor. The piston displacement value of the piston inside the pressure-building cylinder is obtained based on the motor rotor angle signal and the mechanical transmission ratio. The pressure sensor is fault-detected based on a preset cycle. If the pressure sensor is determined to be in a normal state, the displacement estimated pressure value is determined based on the mapping relationship between the piston displacement value and the pressure. If the steady-state braking condition is met based on the vehicle status signal, a first target deviation value is determined based on the braking pressure value fed back by the pressure sensor and the displacement estimated pressure value, and the first target deviation value is updated to the displacement range corresponding to the piston displacement value. If the pressure sensor is determined to be in a abnormal state, a second target deviation value is determined based on the displacement range corresponding to the piston displacement value. The second target deviation value and the displacement estimated pressure value are superimposed and compensated to obtain the target estimated pressure value, and the closed-loop braking adjustment of the drive motor is performed based on the target estimated pressure value. Therefore, by self-learning and storing steady-state deviation when the pressure sensor is normal, and calling this deviation to compensate for displacement and estimate pressure when the pressure sensor fails, the closed-loop braking control of the motor is maintained. This achieves the safety effect of smoothly continuing the braking pressure after failure and avoiding the sudden drop in braking force and the surge in braking distance caused by the traditional mechanical backup mode.

[0057] Optionally, module 320 is specifically used to determine the motor rotor angle value based on the motor rotor angle signal; obtain the lead parameter of the lead screw assembly, the lead parameter being the linear stroke generated by the nut and the piston driven by the lead screw assembly rotating one revolution; obtain the reduction ratio of the reduction mechanism set between the motor output shaft and the lead screw assembly, the reduction ratio being the ratio of the number of rotations of the motor to the number of rotations of the lead screw assembly; and obtain the piston displacement value of the piston inside the pressure-building cylinder based on x = (θ / (i×360°)) × L, where x represents the piston displacement value, θ represents the motor rotor angle value, i represents the reduction ratio, and L represents the lead parameter.

[0058] Optionally, the update module 330 is specifically used to detect, based on the preset period, whether the amplitude of the brake pressure signal exceeds a preset amplitude upper and lower limit; based on the preset period, whether the rate of change of the brake pressure signal exceeds a preset change threshold; and based on the preset period, whether the internal self-test state of the pressure sensor passes; wherein, if it is determined that the amplitude of the brake pressure signal does not exceed the preset amplitude upper and lower limit, the rate of change of the brake pressure signal does not exceed the preset change threshold, and the internal self-test state of the pressure sensor passes, the state of the pressure sensor is determined to be without abnormality.

[0059] Optionally, the update module 330 is specifically used to obtain the ABS status based on the anti-lock braking system ABS and the ESC status based on the electronic stability control system ESC; when it is determined that both the ABS status and the ESC status are inactive, it determines that the steady-state braking condition is met; wherein, the difference between the braking pressure value and the displacement estimation pressure value is calculated, and the difference is used as the first target deviation value.

[0060] Optionally, the execution module 340 is specifically configured to retrieve the latest stored deviation value corresponding to the displacement interval based on the piston displacement value, and use the deviation value as the second target deviation value; wherein, the sum of the second target deviation value and the displacement estimated pressure value is calculated, and the sum is used as the target estimated pressure value.

[0061] Optionally, the execution module 340 is specifically used to perform rate-of-change limiting processing on the target estimated pressure value based on the target estimated pressure value; and use the limited estimated pressure value as a feedback quantity to maintain the closed-loop braking adjustment of the drive motor until the vehicle comes to a safe stop or the abnormal state of the pressure sensor disappears.

[0062] Optionally, the execution module 340 is specifically used to determine the pressure change rate based on the target estimated pressure value of the current period and the target estimated pressure value of the previous period; if the pressure change rate exceeds a preset pressure change rate, the output is incremented or decremented according to the preset pressure change rate; if the pressure change rate does not exceed the preset pressure change rate, the target estimated pressure value is used as a feedback quantity.

[0063] According to one aspect of the present invention, an electronic device is provided.

[0064] Figure 4 This is a schematic diagram of the structure of an electronic device according to an embodiment of the present invention. Figure 4 As shown, an electronic device may include one or more ( Figure 4 Only one is shown in the image. A processor 102 (which may include, but is not limited to, a microprocessor unit (MPU) or a programmable logic device (PLD)) and a memory 104 for storing data are also shown. In one exemplary embodiment, the electronic device may further include a transmission device 106 for communication functions and an input / output device 108. Those skilled in the art will understand that... Figure 4 The structure shown is for illustrative purposes only and does not limit the structure of the terminal device described above. For example, the terminal device may also include components that are more... Figure 4 The more or fewer components shown, or having the same Figure 4 Equivalent functions or ratios shown Figure 4 The functions shown have more different configurations.

[0065] The memory 104 can be used to store computer programs, such as application software programs and modules, like the computer program corresponding to the EHB pressure sensor redundancy control method in this embodiment of the invention. The processor 102 executes various functional applications and data processing by running the computer program stored in the memory 104, thereby implementing the above-described method. The memory 104 may include high-speed random access memory, and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some instances, the memory 104 may further include memory remotely located relative to the processor 102, and these remote memories can be connected to terminal devices via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0066] The transmission device 106 is used to receive or send data via a network. Specific examples of the network described above may include a wireless network provided by the communication provider of the switching device. In one example, the transmission device 106 includes a Network Interface Controller (NIC), which can connect to other network devices via a base station to communicate with the Internet. In another example, the transmission device 106 may be a Radio Frequency (RF) module used for wireless communication with the Internet.

[0067] This invention proposes a non-transient computer-readable storage medium storing computer instructions for causing the computer to execute an EHB pressure sensor redundancy control method.

[0068] The applicant of this invention has provided a detailed description of the embodiments of the invention in conjunction with the accompanying drawings. However, those skilled in the art should understand that the above embodiments are merely preferred embodiments of the invention. The detailed description is only intended to help readers better understand the spirit of the invention and is not intended to limit the scope of protection of the invention. On the contrary, any improvements or modifications made based on the inventive spirit of the invention should fall within the scope of protection of the invention.

[0069] Furthermore, the functional units in the various embodiments of the present invention can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0070] The storage medium mentioned above can be a read-only memory, a disk, or an optical disk, etc. Although embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the protection scope of the present invention.

Claims

1. A redundancy control method for an EHB pressure sensor, characterized in that, include: S1, Real-time acquisition of dual physical signals within the same cycle, wherein the dual physical signals include the braking pressure signal fed back by the pressure sensor and the motor rotor angle signal fed back by the motor position sensor; S2, based on the motor rotor angle signal and the mechanical transmission ratio, obtain the piston displacement value of the piston inside the pressure-building cylinder; S3, perform fault detection on the pressure sensor based on a preset period. If the pressure sensor is found to be in a normal state, determine the displacement estimated pressure value based on the piston displacement value and the pressure mapping relationship. If the steady-state braking condition is met by judging from the vehicle status signal, determine the first target deviation value based on the braking pressure value fed back by the pressure sensor and the displacement estimated pressure value, and update the first target deviation value to the displacement range corresponding to the piston displacement value. S4, if the pressure sensor is determined to be in an abnormal state, a second target deviation value is determined based on the displacement range corresponding to the piston displacement value. The second target deviation value and the displacement estimated pressure value are superimposed and compensated to obtain a target estimated pressure value. Based on the target estimated pressure value, the closed-loop braking adjustment of the drive motor is executed.

2. The EHB pressure sensor redundancy control method according to claim 1, characterized in that, Based on the motor rotor angle signal and the mechanical transmission ratio, the piston displacement value of the piston inside the pressure-building cylinder is obtained, including: The motor rotor angle value is determined based on the motor rotor angle signal; Obtain the lead parameter of the lead screw assembly, wherein the lead parameter is the linear stroke of the nut driven by the lead screw assembly and the piston generated by one revolution of the lead screw assembly; Obtain the reduction ratio of the reduction mechanism set between the motor output shaft and the lead screw assembly, wherein the reduction ratio is the ratio of the number of rotations of the motor to the number of rotations of the lead screw assembly; Based on x = (θ / (i × 360°)) × L, the piston displacement value of the piston inside the pressure-building cylinder is obtained, where x represents the piston displacement value, θ represents the motor rotor angle value, i represents the reduction ratio, and L represents the lead parameter.

3. The EHB pressure sensor redundancy control method according to claim 1, characterized in that, Fault detection of the pressure sensor is performed based on a preset period, including: Based on the preset period, detect whether the amplitude of the braking pressure signal exceeds the preset upper and lower limits of amplitude; Based on the preset period, detect whether the rate of change of the braking pressure signal exceeds a preset change threshold. Based on the preset cycle, it is detected whether the internal self-test status of the pressure sensor has passed; Specifically, if the amplitude of the braking pressure signal does not exceed the preset upper and lower limits of amplitude, the rate of change of the braking pressure signal does not exceed the preset change threshold, and the internal self-test of the pressure sensor passes, the pressure sensor is determined to be in a state of no abnormality.

4. The EHB pressure sensor redundancy control method according to claim 1, characterized in that, Determining whether the steady-state braking condition is met based on the vehicle state signal includes: The ABS status is obtained based on the anti-lock braking system (ABS), and the ESC status is obtained based on the electronic stability control system (ESC). If it is determined that both the ABS state and the ESC state are inactive, then the steady-state braking condition is satisfied. The determination of the first target deviation value based on the braking pressure value fed back by the pressure sensor and the displacement estimation pressure value includes: Calculate the difference between the braking pressure value and the displacement estimation pressure value, and use the difference as the first target deviation value.

5. The EHB pressure sensor redundancy control method according to claim 1, characterized in that, Determining the second target deviation value based on the displacement range corresponding to the piston displacement value includes: Based on the piston displacement value, retrieve the latest stored deviation value corresponding to the displacement interval, and use the deviation value as the second target deviation value; The method involves superimposing and compensating the second target deviation value and the estimated displacement pressure value to obtain the target estimated pressure value, including: Calculate the sum of the second target deviation value and the estimated displacement pressure value, and use the sum as the target estimated pressure value.

6. The EHB pressure sensor redundancy control method according to claim 1, characterized in that, Based on the target estimated pressure value, closed-loop braking adjustment of the drive motor is performed, including: Based on the target estimated pressure value, the rate of change of the target estimated pressure value is limited; The estimated pressure value after the limit is used as feedback to maintain the closed-loop braking adjustment of the drive motor until the vehicle comes to a safe stop or the abnormal state of the pressure sensor disappears.

7. The EHB pressure sensor redundancy control method according to claim 1, characterized in that, The rate of change limiting process is applied to the estimated target pressure value, including: The pressure change rate is determined based on the target estimated pressure value for the current period and the target estimated pressure value for the previous period. If the pressure change rate exceeds the preset pressure change rate, the output will be increased or decreased according to the preset pressure change rate. If the pressure change rate does not exceed the preset pressure change rate, the target estimated pressure value is used as the feedback value.

8. A redundant control system for an EHB pressure sensor, characterized in that, include: The acquisition module is used to acquire dual physical signals in real time within the same period, wherein the dual physical signals include the braking pressure signal fed back by the pressure sensor and the motor rotor angle signal fed back by the motor position sensor. The module is used to obtain the piston displacement value of the piston inside the pressure-building cylinder based on the motor rotor angle signal and the mechanical transmission ratio. The update module is used to perform fault detection on the pressure sensor based on a preset period. When it is determined that the pressure sensor is in a normal state, the estimated displacement pressure value is determined based on the piston displacement value and the pressure mapping relationship. When the steady-state braking condition is met by judging through the vehicle status signal, the first target deviation value is determined based on the braking pressure value fed back by the pressure sensor and the estimated displacement pressure value, and the first target deviation value is updated to the displacement range corresponding to the piston displacement value. The execution module is used to determine a second target deviation value based on the displacement range corresponding to the piston displacement value when the state of the pressure sensor is determined to be abnormal, to superimpose the second target deviation value and the displacement estimated pressure value to obtain a target estimated pressure value, and to perform closed-loop braking adjustment of the drive motor based on the target estimated pressure value.

9. An electronic device, characterized in that, include: At least one processor; as well as A memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor to enable the at least one processor to perform the method of any one of claims 1 to 7.

10. A non-transitory computer-readable storage medium storing computer instructions, characterized in that, The computer instructions are used to cause the computer to perform the method according to any one of claims 1 to 7.

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