Vehicle brake booster system control method, ECU controller, medium and product

Abstract

The invention discloses a vehicle brake boosting system control method, an ECU controller, a medium and a product, and relates to the field of data processing. The method is applied to an ECU controller of a vehicle brake booster system and comprises the steps that target brake pressure is determined according to the displacement and speed of a brake pedal, and then the feed-forward target position of a master cylinder push rod is calculated; acquiring actual pressure through a pressure sensor, and comparing the actual pressure with target pressure to determine a corrected target position so as to obtain a final target position; calculating a feed-forward target current of the power-assisted motor according to the final target position; and acquiring an actual position signal by using a motor angle sensor, comparing the actual position signal with a final target position, determining a corrected target current, finally determining and conveying the final target current to a power-assisted motor, and driving a main cylinder push rod to apply braking force. The stability and reliability of the braking system can be improved, and therefore the braking performance and safety of the vehicle are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of data processing, and in particular to a vehicle brake booster system control method, an ECU controller, a medium and a product. Background Art

[0002] Electric brake booster (EHB) has become the mainstream solution to replace traditional vacuum boosters. EHB uses an electric motor to replace the traditional vacuum booster to provide the driver with brake assistance, with the advantages of faster response speed and higher control accuracy. Its core control logic is to drive the brake master cylinder piston push rod through the electric motor to achieve the establishment of hydraulic pressure in the master cylinder, and adjust the output of the booster motor through the master cylinder push rod position feedback.

[0003] The commonly used control strategy is to control the output of the motor by monitoring the position of the master cylinder push rod. However, factors such as brake system aging, pipeline softening, and bubble accumulation will affect the effectiveness of this control strategy, resulting in a decrease in the stability and reliability of the brake assist system, affecting the braking force and causing driving safety risks. Summary of the invention

[0004] In view of the above-mentioned technical problems and defects, the purpose of the present invention is to provide a vehicle brake booster system control method, ECU controller, medium and product, which can improve the stability and reliability of the brake system, thereby improving the braking performance and safety of the vehicle.

[0005] To achieve the above-mentioned purpose, in the first aspect, the present invention provides a vehicle brake booster system control method, which is applied to an ECU controller of a vehicle brake booster system, wherein the vehicle brake booster system also includes a brake pedal, a brake master cylinder, a master cylinder pressure sensor, a master cylinder push rod, a booster motor and a motor angle sensor; when the vehicle brakes, the booster motor is connected to the master cylinder push rod, and the master cylinder push rod is connected to the brake master cylinder; the method includes: determining a target brake pressure of the brake fluid in the brake master cylinder according to the displacement and speed of the brake pedal; determining a feedforward target position of the master cylinder push rod based on the target brake pressure; obtaining an actual brake pressure of the brake master cylinder through the master cylinder pressure sensor force; determine the corrected target position of the master cylinder push rod according to the actual braking pressure and the target braking pressure; determine the final target position of the master cylinder push rod based on the feedforward target position and the corrected target position; determine the feedforward target current of the power-assisted motor according to the final target position; obtain the actual position signal of the master cylinder push rod through the motor angle sensor; determine the corrected target current of the power-assisted motor according to the actual position signal and the final target position; determine the final target current based on the feedforward target current and the corrected target current; transmit the final target current to the power-assisted motor, so that the power-assisted motor drives the master cylinder push rod to apply force to the brake master cylinder.

[0006] The present invention realizes refined control of the braking process by accurately calculating the target braking pressure, dynamically adjusting the position of the master cylinder push rod, and optimizing the current of the boost motor. First, according to the displacement and speed of the brake pedal, the target braking pressure of the brake fluid in the brake master cylinder is accurately determined to provide an accurate benchmark for subsequent control. Secondly, the actual braking pressure is obtained in real time by the pressure sensor, and compared with the target pressure, and the corrected target position of the master cylinder push rod is dynamically adjusted to ensure accurate tracking of the braking pressure. Thirdly, based on the feedforward target position and the corrected target position, the final target position of the master cylinder push rod is determined, and the feedforward target current of the boost motor is calculated accordingly to achieve accurate control of the boost motor. In addition, the actual position signal of the master cylinder push rod is obtained by the motor angle sensor, and the corrected target current of the boost motor is further adjusted, and the final target current is finally determined and transmitted to the boost motor to ensure that the brake master cylinder applies an accurate force. Utilization method The present invention improves the response speed and control accuracy of the braking system, enhances the stability and reliability of the brake boost system, improves the braking performance and safety of the vehicle, and provides a strong guarantee for the safe driving of the vehicle.

[0007] In combination with some embodiments of the first aspect, in some embodiments, the corrected target position of the master cylinder push rod is determined based on the actual braking pressure and the target braking pressure, including: calling a preset pressure robust PI control module, processing the actual braking pressure and the target braking pressure, and obtaining the corrected target position.

[0008] By adopting the technical solution of the above embodiment, by calling the preset pressure robust PI control module, the method can accurately process the deviation between the actual brake pressure and the target brake pressure, thereby dynamically adjusting the corrected target position of the master cylinder push rod. This advanced control strategy not only improves the response speed and control accuracy of the brake system, but also enhances the system's adaptability to various working conditions, such as temperature fluctuations, brake fluid aging, etc., ensuring the stability and reliability of the braking process.

[0009] In combination with some embodiments of the first aspect, in some embodiments, the corrected target current of the power-assisted motor is determined based on the actual position signal and the final target position, including: calling a preset current robust PI control module, processing the actual position signal and the final target position, and obtaining the corrected target current.

[0010] By adopting the technical solution of the above embodiment, the current robust PI control module is called to compensate the deviation between the actual position of the master cylinder push rod and the final target position in real time, and the corrected target current is calculated. Such a control mechanism significantly improves the accuracy of the power-assisted motor's control of the master cylinder push rod position, reduces the position error, thereby optimizing the braking effect, improving driving safety, and possibly extending the service life of the motor and the braking system.

[0011] In combination with some embodiments of the first aspect, in some embodiments, after the final target current is transmitted to the power-assisted motor so that the power-assisted motor drives the master cylinder push rod to apply force to the brake master cylinder, it also includes: obtaining the current push rod position and expected position range of the master cylinder push rod, and the expected position range is determined based on the final target current; judging whether there is an abnormal situation in the brake master cylinder based on the current push rod position and the expected position range; if so, issuing an alarm prompt to the driver.

[0012] By adopting the technical solution of the above embodiment, after the final target current is transmitted to the power-assisting motor, the system further monitors the current position and expected position interval of the master cylinder push rod. By comparing the current push rod position with the expected position interval, the method can accurately determine whether there is an abnormality in the brake master cylinder. If an abnormality is detected, the system will promptly issue an alarm to the driver. Such a safety mechanism is of great significance for preventing brake failure and improving driving safety.

[0013] In combination with some embodiments of the first aspect, in some embodiments, determining the target brake pressure of the brake fluid in the master cylinder according to the displacement and speed of the brake pedal includes: inputting the displacement and speed of the brake pedal into a preset displacement speed pressure function to obtain the target brake pressure, and the displacement speed pressure function includes: ; in, P ( x,v ) represents the hydraulic pressure in the brake master cylinder, x represents the displacement of the brake pedal, v Represents the speed of the brake pedal, C 1 , C 2 , C 3 , C 4 are constant coefficients, V 0 represents the initial volume of the inner cavity of the brake master cylinder, and A represents the cross-sectional area of ​​the brake master cylinder.

[0014] By adopting the technical solution of the above embodiment, the target brake pressure can be accurately calculated by inputting the displacement and speed of the brake pedal into the preset displacement speed pressure function. This step is crucial to the control of the entire brake booster system because it provides an accurate initial target pressure value for the subsequent master cylinder push rod position control and booster motor current control, thereby ensuring the stability and effectiveness of the braking process.

[0015] In combination with some embodiments of the first aspect, in some embodiments, determining the feedforward target position of the master cylinder push rod based on the target brake pressure includes: inputting the target brake pressure into a preset pressure position function to obtain the feedforward target position, and the pressure position function includes:

[0016] in, L ( P ) represents the displacement of the master cylinder push rod, P represents the hydraulic pressure of the brake master cylinder, a、b、c、d、m、f、 g、h、i、j are constant coefficients, e is a natural constant, P 1 and P 2 is the preset pressure threshold.

[0017] By adopting the technical solution of the above embodiment, the feedforward target position of the master cylinder push rod is determined by using the pressure position function, ensuring the accurate mapping from the target brake pressure to the push rod position. This precise control is crucial to achieving the ideal braking effect, because it directly affects the distribution and pressure buildup of the brake fluid in the brake master cylinder, and thus affects the braking performance and driving comfort of the vehicle.

[0018] In combination with some embodiments of the first aspect, in some embodiments, determining the feedforward target current of the power-assisted motor according to the final target position includes: inputting the final target position into a preset position current function to obtain the feedforward target current, and the position current function includes: ; Where, I(L) represents the feedforward target current, a、β、γ、δ、ϵ、ζ、η、θ、ι、κ、λ are constant coefficients respectively, L represents the final target position, L 1 and L 2 The position segment point.

[0019] By adopting the technical solution of the above embodiment, the feedforward target current of the power-assist motor is determined by the position current function, and an accurate current instruction is provided to the power-assist motor to drive the master cylinder push rod to reach the final target position. This process is critical to ensure that the brake assist system responds efficiently and accurately to the driver's braking request, which helps to improve the braking performance and the overall safety of the vehicle.

[0020] In a second aspect, an embodiment of the present invention provides an ECU controller, comprising: one or more processors and a memory; the memory is coupled to the one or more processors, the memory is used to store computer program code, the computer program code includes computer instructions, and the one or more processors call the computer instructions to enable the ECU controller to execute the method described in the first aspect or the second aspect, and any possible implementation method in the first aspect or the second aspect.

[0021] In a third aspect, the present invention provides a computer-readable storage medium, comprising instructions, which, when executed on the ECU controller, cause the ECU controller to execute the method described in the first aspect or the second aspect, and any possible implementation of the first aspect or the second aspect.

[0022] In a fourth aspect, the present invention provides a computer program product comprising instructions, which, when the above-mentioned computer program product runs on the above-mentioned ECU controller, enables the above-mentioned ECU controller to execute the method described in the first aspect or the second aspect, and any possible implementation method of the first aspect or the second aspect.

[0023] It can be understood that the ECU controller provided in the second aspect, the storage medium provided in the third aspect, and the computer program product provided in the fourth aspect are all used to execute the method provided by the present invention. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding method, which will not be repeated here.

[0024] One or more technical solutions provided by the present invention have at least the following technical effects or advantages: 1. By accurately calculating the target brake pressure in the master cylinder and dynamically adjusting the position of the master cylinder push rod using the pressure robust PI control module, precise control of the brake pressure is achieved. This precise pressure control not only ensures the reliability and stability of vehicle braking, but also improves the timeliness of the brake response, thus providing effective safety protection for the driver in emergency situations.

[0025] 2. The position current function and the current robust PI control module work together to optimize the response of the power-assisted motor to the position of the master cylinder push rod. By adjusting the current of the power-assisted motor in real time, it ensures that the master cylinder push rod can quickly and accurately reach the expected position, which directly improves the efficiency and performance of the braking system, while reducing energy consumption and increasing the driving economy of the vehicle.

[0026] 3. The robustness of the brake boost system is enhanced by the comprehensive use of pressure robust PI control and current robust PI control strategies. The system can adapt to various working conditions, such as brake fluid leakage, pipeline aging, etc., and adjust the control strategy in time to compensate for system deviations and prevent brake failure. In addition, by monitoring the master cylinder push rod position and issuing an alarm prompt when abnormal, the safety of the system is further improved to ensure the safety of the driver and passengers. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The drawings herein are incorporated into and constitute a part of the specification, showing embodiments consistent with the present invention, and together with the specification, are used to explain the principles of the present invention. Obviously, the drawings described below are only some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work. In the drawings: Figure 1 is a schematic diagram of the architecture of a vehicle brake booster system according to an embodiment of the present invention; Figure 2 is a flow chart of a vehicle brake booster system control method according to an embodiment of the present invention; Figure 3 It is a schematic diagram of the architecture of an electronic device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0028] The terms used in the following embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to be limiting of the present invention. As used in the specification of the present invention, the singular expressions "a", "a", "above", "the" and "this" are intended to also include plural expressions, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used in the present invention refers to any or all possible combinations comprising one or more of the listed items.

[0029] In the following, the terms "first" and "second" are used for descriptive purposes only and should not be understood as implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present invention, unless otherwise specified, the meaning of "plurality" is two or more.

[0030] It should also be noted that, unless otherwise clearly specified and limited, in the embodiments of the present invention, the terms such as "setting" and "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two components; it can be a wired communication connection or a wireless communication connection. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. The embodiments of the present invention are described in detail below.

[0031] The embodiment of the present invention provides a vehicle brake booster system, such as Figure 1As shown, it includes an ECU controller 101, a brake pedal 102, a brake master cylinder 103, a master cylinder pressure sensor 104, a master cylinder push rod 105, a power-assisting motor 106 and a motor angle sensor 107. When the vehicle brakes, the power-assisting motor 106 is connected to the master cylinder push rod 105, and the master cylinder push rod 105 is connected to the brake master cylinder 103.

[0032] Among them, ECU (electronic control unit) is also called a driving computer, and its main purpose is to control the driving state of the car and realize its various functions. In this embodiment, the ECU controller 101 is the core control unit of the vehicle's brake booster system, responsible for receiving and processing signals from the brake pedal 102, the master cylinder pressure sensor 104 and the motor angle sensor 107. Based on these signals, the ECU controller 101 calculates the target brake pressure, target position and target current through a preset control algorithm, and makes real-time adjustments based on the deviation between the actual measured value and the target value to ensure accurate control and stable operation of the brake system.

[0033] The brake pedal 102 is a direct interface between the driver and the vehicle braking system, and its displacement and speed reflect the driver's braking intention. When the driver steps on the brake pedal 102, the displacement and speed signals of the brake pedal 102 are collected by the sensor and transmitted to the ECU controller 101 as a basis for calculating the target brake pressure.

[0034] The master cylinder 103 is a key component in the brake system, and the hydraulic pressure inside it directly determines the braking force of the vehicle. The master cylinder 103 is connected to the booster motor 106 through the master cylinder push rod 105. When the booster motor 106 drives the master cylinder push rod 105 to move, the hydraulic pressure inside the master cylinder 103 changes, thereby achieving the pressurization of the brake fluid and the output of the braking force.

[0035] The master cylinder pressure sensor 104 is mounted on the brake master cylinder 103 and is used to monitor the actual hydraulic pressure in the brake master cylinder 103 in real time. The sensor feeds back the measured pressure signal to the ECU controller 101 for comparison with the target brake pressure and pressure adjustment according to the deviation.

[0036] The master cylinder push rod 105 is a key component connecting the power-assist motor 106 and the brake master cylinder 103. Its function is to convert the rotational motion of the power-assist motor 106 into linear motion, thereby pushing the piston in the brake master cylinder 103 and changing the hydraulic pressure in the brake master cylinder 103. The position signal of the master cylinder push rod 105 is fed back to the ECU controller 101 through the motor angle sensor 107, which is used to accurately control the movement of the power-assist motor 106.

[0037] The booster motor 106 is the power source in the brake booster system, and its main function is to drive the master cylinder push rod 105 to move according to the instructions of the ECU controller 101. The output torque and speed of the booster motor 106 directly affect the movement speed of the master cylinder push rod 105 and the hydraulic pressure in the brake master cylinder 103, thereby determining the braking force of the vehicle.

[0038] The motor angle sensor 107 is connected to the power-assisted motor 106 and is used to monitor the rotation angle of the power-assisted motor 106 in real time, thereby indirectly reflecting the position of the master cylinder push rod 105. The sensor feeds back the measured angle signal to the ECU controller 101 for comparison with the target position and position adjustment according to the deviation.

[0039] In some embodiments, the system also includes a foot feel simulator, which simulates the hydraulic pressure feedback in a traditional braking system to provide the driver with a familiar braking feel. The pedal position sensor can monitor and record the displacement of the pedal in real time, that is, the depth of the driver's pedal. The pedal position sensor converts the displacement signal into an electrical signal and transmits it to the ECU controller. The controller calculates the required target brake pressure based on these signals and generates the corresponding braking force by controlling the power-assisted motor. Such a structural design ensures the responsiveness, accuracy and driver comfort of the braking system.

[0040] The present embodiment provides a vehicle brake boost system control method, which is applied to the ECU controller of the above-mentioned vehicle brake boost system (hereinafter referred to as the system). The present embodiment realizes the precise control of the brake master cylinder push rod position and the boost motor current by comprehensively using feedforward control and feedback control, and significantly improves the response speed and control accuracy of the brake system. Specifically, the target brake pressure is first determined according to the displacement and speed of the brake pedal, and then the feedforward target position of the master cylinder push rod is determined based on the target brake pressure, the actual brake pressure is obtained through the master cylinder pressure sensor, and the corrected target position is determined according to the difference between the actual pressure and the target pressure, and finally the feedforward target position is combined with the corrected target position to determine the final target position of the master cylinder push rod. At the same time, the method also obtains the actual position signal of the master cylinder push rod through the motor angle sensor, and determines the corrected target current according to the difference between the actual position signal and the final target position, and finally the feedforward target current is combined with the corrected target current to determine the final target current of the boost motor. This comprehensive control strategy can not only quickly respond to the driver's braking needs, but also effectively compensate for the uncertainty and interference in the system, ensure the stability and reliability of the braking system, and thus significantly improve the braking performance and safety of the vehicle.

[0041] The following is combined with Figure 2 The method of this embodiment is specifically described, which specifically includes the following steps: Step 201, determining the target brake pressure of the brake fluid in the master cylinder according to the displacement and speed of the brake pedal.

[0042] Specifically, the sensor installed on the brake pedal collects the displacement signal and speed signal of the brake pedal in real time, which reflects the driver's braking intention and the intensity of the braking demand. Then, the electronic control unit (ECU) of the vehicle's brake boost system receives these signals and processes them according to the preset control strategy and algorithm.

[0043] In this embodiment, the ECU controller uses a preset mathematical model or table lookup method to map the displacement and speed of the brake pedal to the target brake pressure. This model or table is pre-set based on the braking characteristics of the vehicle, the braking habits of the driver, and the performance requirements of the braking system. The mathematical model can establish a calculation formula for the target brake pressure based on the displacement and speed of the brake pedal through physical principles and system characteristics. The table lookup method is a method of finding the target value through a pre-established table. In the vehicle brake boost system, a table can be established in advance through experiments or simulations, and the table records the target brake pressure values ​​under different brake pedal displacement and speed combinations. When the target brake pressure needs to be determined, the ECU controller searches the table for the corresponding target brake pressure value based on the real-time collected brake pedal displacement and speed signals. The advantages of the table lookup method are simple and intuitive, easy to implement, especially when the system characteristics are more complex or difficult to describe with a simple mathematical model, the table lookup method can provide a more accurate target brake pressure value.

[0044] When calculating the target brake pressure, the ECU will comprehensively consider the size of the brake pedal displacement, the speed, and possible braking scenarios to ensure that the brake pressure can meet the braking requirements while ensuring the comfort and safety of the braking process. Finally, the ECU controller determines the target brake pressure of the brake fluid in the brake master cylinder based on the calculation results and uses it as a reference value for subsequent control processes.

[0045] Step 202: Determine a feedforward target position of the master cylinder push rod based on the target brake pressure.

[0046] Specifically, a pre-set pressure-position correspondence can be used. This pressure-position correspondence is based on the physical characteristics of the brake master cylinder and the system design. The ECU controller maps the target brake pressure to the corresponding master cylinder push rod position through the pressure-position correspondence. This feedforward target position is the position that the system expects the master cylinder push rod to reach in order to generate the required target brake pressure.

[0047] In this embodiment, the pressure-position correspondence is obtained mainly through two methods: experimental testing and theoretical modeling. In the experimental test, the brake master cylinder is installed on a special test bench, and the known target brake pressure is gradually applied. At the same time, a high-precision displacement sensor is used to measure the corresponding master cylinder push rod position. After recording multiple sets of pressure and position data, the pressure-position curve is obtained by data fitting. In terms of theoretical modeling, based on the structural parameters of the brake master cylinder, such as cylinder diameter, piston area, initial volume, etc., combined with the physical properties of the brake fluid, the principles of fluid mechanics and elastic mechanics are used to establish a mathematical model describing the relationship between pressure and position, and then the pressure-position correspondence is generated through simulation or analytical calculation. These two methods complement each other. Experimental testing provides actual data verification, and theoretical modeling is used for prediction and optimization. Finally, an accurate pressure-position correspondence is obtained, which provides a key basis for the precise control of the braking system.

[0048] Step 203: Acquire the actual brake pressure of the brake master cylinder through the master cylinder pressure sensor.

[0049] Specifically, the master cylinder pressure sensor converts the detected pressure signal into an electrical signal and transmits the electrical signal to the ECU controller. After receiving the signal, the ECU controller processes and analyzes the electrical signal to obtain the actual brake pressure value in the brake master cylinder.

[0050] Step 204: Determine a corrected target position of the master cylinder push rod according to the actual brake pressure and the target brake pressure.

[0051] Specifically, the ECU controller calculates the corrected target position by comparing the difference between the actual brake pressure and the target brake pressure. For example, the ECU controller adjusts the position of the master cylinder push rod according to the pressure error (target brake pressure minus actual brake pressure) to compensate for the deviation between the actual pressure and the target pressure. The corrected target position is calculated by a preset control algorithm (such as a PI control algorithm), which dynamically adjusts the position of the master cylinder push rod according to the size and change trend of the pressure error to ensure that the brake system can accurately reach the target brake pressure.

[0052] Step 205, determining the final target position of the master cylinder push rod based on the feedforward target position and the corrected target position.

[0053] Specifically, the ECU controller combines the feedforward target position with the corrected target position to determine the final target position of the master cylinder push rod. The feedforward target position is the initial position calculated directly based on the target brake pressure, while the corrected target position is the compensated position adjusted according to the difference between the actual brake pressure and the target brake pressure. The final target position is the combined result of these two positions, which is calculated by adding the feedforward target position and the corrected target position or by a fusion algorithm to ensure that the master cylinder push rod can accurately reach the desired position, thereby achieving precise braking control.

[0054] In some embodiments, this step may specifically include: calling a preset pressure robust PI control module, processing the actual braking pressure and the target braking pressure, and obtaining the corrected target position.

[0055] Specifically, the pressure-robust PI control module first receives the actual brake pressure and the target brake pressure as input signals, and evaluates the current state of the brake system by calculating the difference between the two, namely the pressure error. Then, the module uses the preset proportional gain and integral gain to perform proportional and integral operations on the pressure error to generate a control signal that is proportional to the pressure error and takes into account the historical error accumulation. After processing, this control signal is used as the basis for correcting the target position to adjust the position of the master cylinder push rod to compensate for the deviation between the actual brake pressure and the target brake pressure. In this way, the pressure-robust PI control module can dynamically adjust the position of the master cylinder push rod to ensure that the brake system can accurately reach the target brake pressure under various working conditions, thereby achieving a stable and reliable braking effect.

[0056] The working principle of the pressure robust PI control module is based on the proportional-integral (PI) control strategy. It monitors and adjusts the pressure in the brake system in real time to ensure that the position of the master cylinder push rod can accurately reach the target position, thereby achieving precise control of the brake pressure. The following is the specific working principle of the pressure robust PI control module: (1) Pressure error calculation: Obtain the actual brake pressure P through the master cylinder pressure sensor actual and the target brake pressure P target Compare and calculate the pressure error e P :e P =P target −P actual .

[0057] (2) Proportional control: According to the pressure error e P , through the proportional gain K p Perform proportional control and generate proportional control output u p :u p =K p ⋅e PThe role of proportional control is to respond quickly to pressure errors, allowing the system to quickly adjust the position of the master cylinder push rod.

[0058] (3) Integral control: In order to eliminate the steady-state error, the integral gain K i Pressure error e P Integrate to generate integral control output u i :u i =K i ⋅∫e P The role of integral control is to accumulate historical errors to ensure that the system can eliminate pressure errors over a long period of time and achieve steady-state accuracy.

[0059] (4) Robust design: In order to cope with the uncertainty and disturbance in the system, the pressure robust PI control module adopts a robust control algorithm. This algorithm optimizes the controller parameters so that the system can maintain good control performance under the conditions of parameter changes, external disturbances and model uncertainty. Specifically, the robust control algorithm dynamically adjusts the proportional gain K according to the actual response of the system. p And the integral gain K i To ensure that the system can operate stably under different working conditions.

[0060] (5) Correction of target position calculation: The proportional control output u p And integral control output u i Add together to get the total control output u total :u total =u p +u i Then, according to the total control output u total , adjust the feedforward target position L of the master cylinder push rod ff , get the corrected target position L corrected :L corrected =L ff +u total . (6) Output the corrected target position: Finally, the corrected target position L corrected The output is used by the subsequent position control module to ensure that the master cylinder push rod can accurately reach the target position and achieve precise control of the brake pressure.

[0061] Through the above steps, the pressure robust PI control module can monitor and adjust the pressure in the brake system in real time, ensuring that the position of the master cylinder push rod can accurately reach the target position, thereby achieving precise control of the brake pressure and improving the performance and safety of the brake system.

[0062] Step 206 , determining the feedforward target current of the power-assisting motor according to the final target position.

[0063] Specifically, a pre-established position-current mapping relationship can be used, which describes the correspondence between the master cylinder push rod position and the current required by the power-assisting motor. The ECU controller converts the final target position into the corresponding feedforward target current by looking up a table or a mathematical model. The feedforward target current is the initial current required by the power-assisting motor without feedback correction, and is used to drive the master cylinder push rod to the final target position.

[0064] Among them, the position-current mapping relationship can be established by combining experimental testing and theoretical analysis. First, in the experimental stage, the power-assisted motor is connected to the master cylinder push rod, and the actual displacement of the master cylinder push rod under different currents is measured by controlling the motor to output different current values. These data points form a set of position-current correspondences. Then, using these experimental data, combined with the characteristic curve of the motor and the physical model of the braking system, an accurate mapping function is established through mathematical fitting or table lookup. This function can directly convert the target position of the master cylinder push rod into the feedforward target current required by the power-assisted motor. In actual operation, the ECU controller quickly calculates the corresponding feedforward target current based on the final target position of the master cylinder push rod through this mapping relationship, thereby achieving precise control of the power-assisted motor and ensuring efficient and stable operation of the braking system.

[0065] Step 207, obtaining the actual position signal of the master cylinder push rod through the motor angle sensor.

[0066] Among them, the motor angle sensor is installed on the power-assisted motor to monitor the rotation angle of the power-assisted motor in real time. The rotation angle of the power-assisted motor refers to the rotation position of the motor rotor relative to the stator, usually in degrees (°) or radians (rad), which is used to describe the degree of rotation of the motor rotor. In the vehicle brake assist system, the motor angle sensor measures the rotation angle of the motor and converts it into an electrical signal, thereby realizing real-time monitoring and precise control of the motion state of the power-assisted motor.

[0067] When the power-assisted motor drives the master cylinder push rod to move, the motor angle sensor converts the detected angle change into an electrical signal and transmits it to the ECU controller. The ECU controller converts the motor angle signal into the actual position signal of the master cylinder push rod based on the transmission ratio of the power-assisted motor and the mechanical connection relationship of the master cylinder push rod. This process ensures that the system can obtain the precise position information of the master cylinder push rod in real time, providing data support for subsequent position feedback control.

[0068] Step 208 , determining a corrected target current of the power assist motor according to the actual position signal and the final target position.

[0069] Specifically, the ECU controller calculates the corrected target current based on the difference between the actual position signal of the master cylinder push rod and the final target position. Specifically, the ECU controller compares the actual position and the final target position through a position feedback control algorithm (such as a PI control algorithm) to obtain the position error. According to the size and change trend of the position error, the ECU controller dynamically adjusts the output current of the power-assist motor to compensate for the deviation between the actual position and the target position. The corrected target current is a compensation current calculated based on the position error, which is used to adjust the output of the power-assist motor to ensure that the master cylinder push rod can accurately reach the final target position.

[0070] In some embodiments, this step may include: calling a preset current robust PI control module to process the actual position signal and the final target position to obtain the corrected target current.

[0071] Specifically, the current robust PI control module can dynamically adjust the output current of the power assist motor according to the deviation between the actual position signal of the master cylinder push rod and the final target position. The following is the working principle of the current robust PI control module: (1) Signal input: The current robust PI control module receives two main input signals, namely the actual position signal of the master cylinder push rod and the final target position signal. The actual position signal is obtained in real time through the motor angle sensor, reflecting the current precise position of the master cylinder push rod; the final target position is calculated by the feedforward target position and the corrected target position, representing the expected master cylinder push rod position.

[0072] (2) Error calculation: The control module first calculates the position error between the actual position signal and the final target position. This error signal is the basis of position feedback control and is used to evaluate whether the current motor output meets the expected position requirements.

[0073] (3) Proportional control (P): Depending on the size of the position error, the proportional control part will immediately generate a control output proportional to the error. The proportional gain (Kp) determines the strength of the proportional control. A larger proportional gain can make the system respond more quickly to the error, but too high a gain may cause the system to oscillate.

[0074] (4) Integral control (I): The integral control part is responsible for eliminating steady-state errors. It integrates the position error over time and generates a control output that is proportional to the integral of the error. The integral gain (Ki) determines the strength of the integral control. Through integral control, even if there is a small steady-state error, the system can gradually adjust the motor output so that the master cylinder push rod position is close to the final target position.

[0075] (5) Anti-interference design: In order to cope with disturbances and uncertainties in the system, the current robust PI control module adopts a robust control algorithm. This algorithm can adapt to parameter changes, external interference and model uncertainty to a certain extent, ensuring that the control performance of the system is not affected. Specifically, the robust control algorithm optimizes the controller parameters so that the system can maintain good control accuracy and stability under different working conditions.

[0076] (6) Control output: The current robust PI control module generates a corrected target current by combining the outputs of proportional control and integral control. This current signal is used to further adjust the output of the power assist motor so that the actual position of the master cylinder push rod is closer to the final target position. After the current target pressure stabilizes, the input position should be within the predetermined range. If it exceeds this range, it indicates that there may be a problem of brake fluid leakage or insufficient hydraulic pressure, and fault diagnosis is required.

[0077] The current robust PI control module of this embodiment ensures that the power-assisting motor can effectively drive the master cylinder push rod and achieve precise braking control through precise position feedback and intelligent control algorithms, thereby improving the performance and safety of the vehicle braking system.

[0078] Step 209 , determining a final target current based on the feedforward target current and the modified target current.

[0079] Specifically, the ECU controller combines the feedforward target current and the corrected target current to determine the final target current of the power assist motor. The feedforward target current is the initial current calculated directly based on the final target position of the master cylinder push rod, while the corrected target current is the compensation current adjusted based on the difference between the actual position and the final target position. The final target current is the combined result of these two currents, calculated by weighted addition of the feedforward target current and the corrected target current or by some fusion algorithm.

[0080] This process ensures that the output current of the power-assisting motor can meet both the initial control requirements and the real-time feedback adjustment requirements, thereby achieving precise braking control.

[0081] In some embodiments, the final target current can be calculated by a target current function, and the mathematical expression of the target current function is as follows:

[0082] Among them, I final represents the final target current; I ff is the feedforward target current; I corr is the corrected target current; α , β , c and d are the control factors respectively; among them, α Used to adjust the degree of nonlinear fusion, β Used to control the combined strength of the feedforward target current and the corrected target current, c Used to adjust the weight of the feedforward current, d Used to correct the current sensitivity, so as to achieve precise control of the output current of the power assist motor. α , β , c and d, The parameter range can be preliminarily determined through theoretical modeling and numerical simulation, and then fine-tuned through experimental testing and optimization algorithms.

[0083] In the target current function, the hyperbolic tangent function tanh and the natural logarithm function ln are nonlinear functions, which can handle the complex interaction between feedforward and correction current. They can not only respond quickly to small deviations, but also achieve saturation and stability when the current command is large, thereby effectively balancing the dynamic response and steady-state accuracy, ensuring accurate current control under different operating conditions.

[0084] exist In this term, the hyperbolic tangent function tanh normalizes the input value to the range of (−1,1) so that the feedforward target current I ff and corrected target current I corr The sum of changes linearly in a smaller range and tends to saturation in a larger range. I ff + I corr When it is large, the output of the tanh function tends to saturate, preventing excessive current and protecting the motor. α The contribution of this part to the final target current can be adjusted. β Control I ff and I corr The comprehensive strength.

[0085] exist In this term, the logarithmic function ln increases rapidly when the input is close to 1, and the growth rate slows down as the input increases, reflecting the correction target current I corr The contribution to the final target current is gradually reduced to avoid overcorrection. Adjust the contribution of this part to the final target current. c Adjust the sensitivity of the corrected target current, d Controls the input range of the Logarithm function.

[0086] The target current function of this embodiment utilizes the nonlinear characteristics of the hyperbolic tangent function and the logarithmic function to better simulate the changing characteristics of the target current, effectively combining the rapid response of the feedforward control and the precise adjustment of the feedback control, and at the same time enhancing the flexibility and adaptability of the control strategy by introducing adjustable parameters.

[0087] Step 210 , delivering the final target current to the power-assisting motor so that the power-assisting motor drives the master cylinder push rod to apply a force to the brake master cylinder.

[0088] Specifically, the ECU controller transmits the calculated final target current to the booster motor. The booster motor adjusts its output torque and speed according to the received current signal, thereby driving the master cylinder push rod to apply force to the brake master cylinder. This process ensures that the master cylinder push rod can accurately reach the final target position and achieve the required brake pressure.

[0089] By precisely controlling the output current of the power-assist motor, the system can quickly respond to the driver's braking needs, improve the response speed and control accuracy of the braking system, and ensure that the vehicle can achieve safe and reliable braking under various operating conditions.

[0090] Based on the above method steps, this embodiment forms a control architecture in which a pressure loop is nested within a position loop. The target pressure of the pressure PI control module is dynamically adjusted through the real pressure fed back by the pressure sensor, and the displacement of the master cylinder push rod is converted according to the motor angle to ensure the closed-loop stability of the position PI control module. Specifically, the pressure loop serves as an outer loop, and according to the difference between the target braking pressure and the actual braking pressure, the output current of the power-assisted motor is adjusted through the pressure PI controller to quickly respond to the driver's braking needs and accurately control the braking pressure. The position loop serves as an inner loop, and according to the difference between the target position and the actual position of the master cylinder push rod, the output of the power-assisted motor is further fine-tuned through the position PI controller to ensure that the master cylinder push rod can accurately reach the target position. This nested control architecture makes full use of the feedback information of the pressure sensor and the motor angle sensor to achieve precise control and stable operation of the braking system.

[0091] At the same time, in this embodiment, the target pressure stability judgment logic is an important link to ensure the normal operation of the system and timely detection of potential faults. Specifically, when the system pressure is established and stabilized, the input position of the master cylinder push rod should be within a predetermined range. If the input position of the master cylinder push rod exceeds the predetermined range, it means that there may be problems such as brake fluid leakage or insufficient hydraulic pressure. At this time, the system will issue an alarm in time to remind the driver or maintenance personnel to check and maintain. This judgment logic can effectively detect abnormal conditions in the system by monitoring the position of the master cylinder push rod in real time, ensuring the safety and reliability of the braking system.

[0092] In this embodiment, when the system pressure reaches a stable state, the actual position of the master cylinder push rod at this time will be compared with the preset reasonable interval. If the input position of the master cylinder push rod exceeds the reasonable floating range of the estimated interval, this may indicate that there are some problems with the brake system, such as brake fluid leakage, bubble accumulation or other faults. These problems may lead to poor braking effect or brake failure, so the brake system will promptly issue an alarm prompt to the driver or intelligent driving system to remind the user to check and maintain.

[0093] For systems that are being installed for the first time or have insufficient brake fluid, when the electric brake booster is installed on a system with unknown pressure-volume (PV) characteristics, the master cylinder pressure may not reach the target pressure due to lack of brake fluid. If pressure closed-loop control is relied upon alone, the motor may continue to rotate, causing the master cylinder push rod to continue to move forward, which may cause the risk of damage to the master cylinder or burning of the motor due to overcurrent.

[0094] However, the control logic of this embodiment nests a position closed-loop regulation after the pressure loop. Before the master cylinder push rod reaches the maximum stroke, the system has diagnosed the deterioration of the PV characteristics through the pressure-position relationship curve. This information will be fed back to the pressure loop, and the motor will be controlled to keep its stroke at the maximum allowable displacement corresponding to the pressure. Therefore, even in the case of insufficient brake fluid, hardware damage can be avoided and the master cylinder and motor can be protected. In addition, if there is still some brake fluid in the system, the stroke can also guarantee a certain braking force to prevent the system from completely losing power.

[0095] In some embodiments, after step 210, the following steps are further included: Step 211, obtaining the current push rod position and the expected position interval of the master cylinder push rod, wherein the expected position interval is determined according to the final target current.

[0096] Specifically, the ECU controller first accurately measures the current actual position of the master cylinder push rod through the motor angle sensor. Then, based on the final target current calculated previously, an expected position range is inferred using the current-position mapping relationship. This expected position range takes into account the error range allowed by the system to ensure that the system can still work normally even with small deviations. The expected position range is determined in order to compare with the actual position to evaluate whether the master cylinder push rod moves correctly according to the instructions.

[0097] Step 212: Determine whether the master brake cylinder has an abnormality according to the current push rod position and the expected position interval.

[0098] Specifically, the ECU controller compares and analyzes the current actual position of the master cylinder push rod obtained with the expected position range determined previously. If the actual position exceeds the expected position range, this may mean that there is an abnormality in the brake master cylinder, such as hydraulic leakage, power motor failure or other mechanical problems. This comparison is an important part of brake system health monitoring, which helps to detect and deal with potential faults in a timely manner.

[0099] If it is determined that the brake master cylinder is abnormal, proceed to step 213.

[0100] If it is determined that there is no abnormality in the master cylinder, the system will continue to monitor the position of the master cylinder push rod and compare it with the final target position based on the real-time feedback position signal. The ECU controller will use this information to continuously fine-tune the output of the power-assist motor by calculating the feedforward target current and the corrected target current to ensure that the position of the master cylinder push rod accurately tracks the expected trajectory. At the same time, the system will maintain a continuous evaluation of the braking performance to ensure that stable and reliable braking force can be provided under various driving conditions, thereby ensuring the vehicle's driving safety and driving comfort. In addition, the system will also be ready to respond to the driver's next braking request to ensure that the braking system is in the best working condition at all times.

[0101] Step 213: Send an alarm to the driver.

[0102] Specifically, once the ECU controller determines that there is an abnormality in the brake master cylinder through comparison, it will activate the alarm mechanism and send an alarm prompt to the driver through the vehicle's warning system. The alarm prompt may include visual warnings (such as warning lights on the dashboard), auditory warnings (such as alarm sounds) or tactile feedback (such as abnormal feeling of the brake pedal) to ensure that the driver can realize the existence of the problem and take appropriate measures, such as stopping for inspection or contacting professional maintenance services. This step is crucial to ensuring driving safety and timely maintenance of the brake system.

[0103] In some embodiments, step 201 may further specifically include: inputting the displacement and speed of the brake pedal into a preset displacement-speed-pressure function to obtain the target brake pressure, wherein the displacement-speed-pressure function includes: ; in, P ( x,v ) represents the hydraulic pressure in the brake master cylinder, x represents the displacement of the brake pedal, v Represents the speed of the brake pedal, C 1 , C 2 , C 3 , C 4 are constant coefficients, V 0represents the initial volume of the inner cavity of the brake master cylinder, and A represents the cross-sectional area of ​​the brake master cylinder.

[0104] It can be understood that in the specific calculation process, the displacement and speed of the brake pedal are obtained after normalization. x and v .

[0105] Specifically, This term describes the displacement x The static effect on pressure, based on Boyle's law, states that as the displacement x increases, the volume inside the master cylinder decreases and the pressure increases.

[0106] C 2 v This term describes the linear effect of velocity v on pressure, meaning that as pedal velocity increases, pressure increases linearly, compensating for dynamic effects.

[0107] C 3 xv This term describes the displacement x and speed v The coupling effect of indicates that pedal displacement and speed jointly affect the pressure, capturing the synergistic effect.

[0108] C 4 log(1+ v ) This term describes the speed v The logarithmic function means that pressure increases with speed, but the rate of increase slows down at high speeds, simulating the nonlinear effect of pedal feel.

[0109] In this embodiment, based on the physical characteristics and mathematical model of the brake system, a system model is established through simulation software (such as MATLAB, AMESim), and parameter scanning and optimization are performed to preliminarily determine C 1 , C 2 , C 3 , C 4 Then, in the experimental environment, the displacement and speed of the brake pedal are changed, the actual brake pressure is measured, and the experimental data is fitted into the displacement speed pressure function P(x,v) through regression analysis to accurately determine C 1 , C 2 , C 3 , C 4 The value of .

[0110] The displacement-velocity-pressure function of this embodiment captures both static and dynamic behaviors in the braking system, combines linear and nonlinear effects, and considers coupling between parameters.

[0111] The displacement-velocity-pressure function combines displacement and velocity in a way that is consistent with the physical behavior of the brake system. Displacement directly affects the volume in the master cylinder, and velocity introduces dynamic effects. Nonlinearity is introduced using a logarithmic function, which is consistent with human perception and the nonlinear response of mechanical systems. The product of displacement and velocity allows the system to react to the combined effects of pedal displacement and velocity, with a coupled effect.

[0112] In some embodiments, step 202 may further specifically include: inputting the target brake pressure into a preset pressure position function to obtain the feedforward target position, where the pressure position function includes:

[0113] in, L ( P ) represents the displacement of the master cylinder push rod, P represents the hydraulic pressure of the brake master cylinder, a、b、c、d、m、f、 g、h、i、j are constant coefficients, e is a natural constant, P 1 and P 2 is the preset pressure threshold.

[0114] The pressure position function L ( P ) is used to adjust the hydraulic pressure of the brake master cylinder P Calculate the displacement of the master cylinder push rod L This function is a piecewise function, according to the pressure P Different expressions are used to describe the displacement in different ranges L With pressure P The relationship between.

[0115] The first part of the pressure-position function: 0 ≤ P <P 1 , L(P)=a⋅ +b⋅P. In the low pressure range, the relationship between displacement and pressure is usually nonlinear. Using the square root term a⋅ It can capture the rapid change of displacement when the pressure is small, while the linear term b⋅P provides the basic linear relationship. This combination can better fit the behavior of the actual system at low pressure.

[0116] Part II: P 1 ≤P <P 2 , In the medium pressure range, the relationship between displacement and pressure becomes more complicated, and the fractional term Describes the saturation effect of displacement when pressure increases, that is, as pressure increases, the growth rate of displacement gradually slows down. m⋅ln(1+f⋅P) This captures the nonlinear change in displacement as pressure increases, providing additional flexibility to fit real data.

[0117] Part III: P ≥ P2, , in the high pressure range, the relationship between displacement and pressure tends to be stable; the logarithmic term g⋅ln(1+h⋅P) Continue to capture the nonlinear change in displacement as pressure increases, while the exponential term It describes the saturation effect of displacement under high pressure, ensuring that the displacement does not increase indefinitely, but gradually tends to a stable value.

[0118] a、b、c、d、m、f、g、h、i、j These constant coefficients are used to adjust the shape of the function to fit the characteristics of the actual system. They can be determined through experimental data or system modeling. The preset pressure threshold P 1 and P 2 , which is used to divide different pressure ranges to ensure that the function in each range can accurately describe the relationship between displacement and pressure. 1 and P 2 Determined through experimental measurement, theoretical analysis or simulation optimization, these values ​​correspond to the key points where the pressure change in the brake master cylinder causes a significant change in the displacement characteristics of the master cylinder push rod. They are used to divide different control strategies to adapt to the dynamic response of the brake assist system at different pressure stages.

[0119] The pressure position function of this embodiment combines multiple nonlinear functions (such as square root, logarithm, exponent, etc.) in a segmented manner, which can accurately describe the complex relationship between the displacement of the master cylinder push rod and the hydraulic pressure of the brake master cylinder. The function form in each segment is to capture the physical characteristics within a specific pressure range to ensure that accurate displacement control can be provided within the entire pressure range. This design not only improves the control accuracy of the system, but also enhances the robustness and adaptability of the system.

[0120] In some embodiments, step 206 may specifically include: inputting the final target position into a preset position current function to obtain the feedforward target current, and the position current function includes: ; Where, I(L) represents the feedforward target current, a、β、γ、δ、ϵ、ζ、η、θ、ι、κ、λ are constant coefficients respectively, L represents the final target position, L 1 and L 2 The position segment point.

[0121] The first part of the position current function: 0 ≤ L <L 1 , αe βL +γL 2 +δL , through the index term αeβL To simulate the characteristics of the current increasing rapidly with the position in the low position area. γL 2 The first-order term δL further refines the relationship between current and position, providing a smoother transition.

[0122] Part II: L 1 ≤L <L 2 , ϵln(1+ζL)+ηL+θ , through the logarithmic function ϵln(1+ζL) Used to capture the nonlinear characteristics of current growth as the position increases, especially in the mid-position area. The linear term ηL and the constant term θ ensure the continuity and stability of the current.

[0123] Part III: L≥L 2 , , a fractional exponential term is used in this section to simulate the saturation characteristics of the current in the high position area, that is, the current will not increase infinitely. The constant term λ ensures that the current remains at a constant value in the high position area.

[0124] The position current function adapts to the needs of the brake assist system in different operating stages through three different mathematical models, thereby providing optimal performance over the entire operating range. The use of logarithmic and exponential functions to simulate the nonlinear relationship between current and position is more in line with the characteristics of the actual physical system. The function is continuous between different intervals, ensuring a smooth transition of the current, avoiding mutations and improving the stability of the system. Constant coefficient a、β、γ、δ、ϵ、ζ、η、θ、ι、κ、λ It can be obtained through experimental calibration, theoretical analysis or numerical optimization methods to ensure that the position-current function can accurately reflect the relationship between the master cylinder push rod position and the power-assisting motor current.

[0125] L 1 and L 2 They can be determined based on the specific performance requirements and actual operating conditions of the braking system. They can be determined through experimental testing, system modeling analysis, or expert experience. In experimental testing, the response of the braking system at different positions is measured to find the key points where the system response changes significantly; in system modeling analysis, the braking process is simulated by simulation software, and the system output is observed to identify these key positions; expert experience relies on historical data and in-depth understanding of similar systems to estimate these values. These methods help ensure that the segmentation points can accurately reflect the working characteristics of the brake assist system, so that they can be correctly applied in the control algorithm.

[0126] The vehicle brake booster system control method provided in this embodiment achieves precise control of the target brake pressure of the brake fluid in the master cylinder, the position of the master cylinder push rod, and the current of the booster motor through precise calculation and dynamic adjustment.

[0127] First, according to the displacement and speed of the brake pedal, the target brake pressure is calculated using the preset displacement speed pressure function to provide an accurate pressure reference for subsequent control. Then, based on the target brake pressure, the feedforward target position of the master cylinder push rod is determined by the pressure position function, and the corrected target position is calculated according to the difference between the actual brake pressure and the target brake pressure through the pressure robust PI control module, so as to ensure that the master cylinder push rod can accurately reach the expected position. Subsequently, the final target position of the master cylinder push rod is determined by combining the feedforward target position and the corrected target position, and the feedforward target current of the power-assisted motor is calculated accordingly. At the same time, the actual position signal of the master cylinder push rod is obtained through the motor angle sensor, and the corrected target current is calculated according to the difference between the actual position and the final target position using the current robust PI control module, and the final target current is finally determined and transmitted to the power-assisted motor to drive the master cylinder push rod to apply accurate force to the brake master cylinder. In addition, the method also includes obtaining the current push rod position and the expected position interval of the master cylinder push rod after transmitting the final target current, judging whether there is an abnormality in the brake master cylinder, and issuing an alarm prompt to the driver when necessary.

[0128] Through the above steps, the embodiment of the present invention not only realizes the precise control of the brake pressure, push rod position and motor current, improves the response speed and control accuracy of the brake system, but also enhances the robustness and safety of the system, providing a strong guarantee for the safe driving of the vehicle.

[0129] The method provided in the above embodiment can be executed by an ECU controller, which is an electronic device. The following describes the electronic device in the embodiment of the present invention from the perspective of hardware processing. Figure 3 , is a schematic diagram of a physical device structure of an electronic device in an embodiment of the present invention.

[0130] It should be noted that Figure 3 The structure of the electronic device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0131] like Figure 3As shown, the electronic device includes a central processing unit (CPU) 401, which can perform various appropriate actions and processes according to the program stored in the read-only memory (ROM) 402 or the program loaded from the storage part 408 to the random access memory (RAM) 403, such as executing the method described in the above embodiment. In RAM 403, various programs and data required for system operation are also stored. CPU 401, ROM 402 and RAM 403 are connected to each other through bus 404. Input / output (I / O) interface 405 is also connected to bus 404.

[0132] The following components are connected to the I / O interface 405: an input section 406 including an audio input device, a button switch, etc.; an output section 407 including a liquid crystal display (LCD) and an audio output device, an indicator light, etc.; a storage section 408 including a hard disk, etc.; and a communication section 409 including a network interface card such as a LAN (Local Area Network) card, a modem, etc. The communication section 409 performs communication processing via a network such as the Internet. A drive 410 is also connected to the I / O interface 405 as needed. A removable medium 411, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 410 as needed so that a computer program read therefrom is installed into the storage section 408 as needed.

[0133] In particular, according to an embodiment of the present invention, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present invention includes a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a computer program for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through the communication part 409, and / or installed from a removable medium 411. When the computer program is executed by the central processing unit (CPU) 401, various functions defined in the present invention are performed.

[0134] It should be noted that specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the present invention, a computer-readable storage medium may be any tangible medium containing or storing a program that may be used by or in combination with an instruction execution system, apparatus, or device.

[0135] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present invention. Each box in the flowchart or block diagram may represent a module, a program segment, or a part of a code, and the above-mentioned module, program segment, or a part of a code contains one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions marked in the box may also occur in an order different from that marked in the accompanying drawings.

[0136] Specifically, the electronic device of this embodiment includes a processor and a memory, the memory is coupled to one or more processors, the memory is used to store computer program code, the computer program code includes computer instructions, and one or more processors call the computer instructions to enable the electronic device to execute the method provided by the above embodiment.

[0137] As another aspect, the present invention further provides a computer-readable storage medium, which may be included in the electronic device described in the above embodiment; or may exist independently without being assembled into the electronic device. The above storage medium carries one or more computer programs, and when the above one or more computer programs are executed by a processor of the electronic device, the electronic device implements the method provided in the above embodiment.

[0138] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

[0139] As used in the above embodiments, the term "when..." may be interpreted to mean "if..." or "after..." or "in response to determining..." or "in response to detecting...", depending on the context. Similarly, the phrases "upon determining..." or "if (the stated condition or event) is detected" may be interpreted to mean "if determining..." or "in response to determining..." or "upon detecting (the stated condition or event)" or "in response to detecting (the stated condition or event)", depending on the context.

[0140] Those skilled in the art can understand that to implement all or part of the processes in the above-mentioned embodiments, the processes can be completed by computer programs to instruct related hardware, and the programs can be stored in computer-readable storage media. When the programs are executed, they can include the processes of the above-mentioned method embodiments. The aforementioned storage media include: ROM or random access memory RAM, magnetic disk or optical disk and other media that can store program codes.

Claims

1. A vehicle brake booster system control method, characterized in that: An ECU controller applied to a vehicle brake booster system, the vehicle brake booster system further comprising a brake pedal, a brake master cylinder, a master cylinder pressure sensor, a master cylinder push rod, a booster motor and a motor angle sensor; when the vehicle brakes, the booster motor is connected to the master cylinder push rod, and the master cylinder push rod is connected to the brake master cylinder; the method comprises: determining a target brake pressure of the brake fluid in the master cylinder according to the displacement and speed of the brake pedal; determining a feedforward target position of the master cylinder push rod based on the target brake pressure; Acquiring the actual brake pressure of the brake master cylinder by means of the master cylinder pressure sensor; determining a corrected target position of the master cylinder push rod according to the actual brake pressure and the target brake pressure; Determining a final target position of the master cylinder push rod based on the feedforward target position and the corrected target position; Determining a feedforward target current of the power-assist motor according to the final target position; Acquiring the actual position signal of the master cylinder push rod through the motor angle sensor; Determining a corrected target current of the power assist motor according to the actual position signal and the final target position; determining a final target current based on the feedforward target current and the corrected target current; The final target current is delivered to the booster motor, so that the booster motor drives the master cylinder push rod to apply a force to the brake master cylinder.

2. The method according to claim 1, characterized in that The step of determining the corrected target position of the master cylinder push rod according to the actual brake pressure and the target brake pressure comprises: A preset pressure robust PI control module is called to process the actual braking pressure and the target braking pressure to obtain the corrected target position.

3. The method according to claim 1, characterized in that The step of determining the corrected target current of the power assist motor according to the actual position signal and the final target position includes: The preset current robust PI control module is called to process the actual position signal and the final target position to obtain the corrected target current.

4. The method according to claim 1, characterized in that: After the final target current is transmitted to the booster motor so that the booster motor drives the master cylinder push rod to apply force to the brake master cylinder, the method further includes: Acquire a current push rod position and an expected position interval of the master cylinder push rod, wherein the expected position interval is determined according to the final target current; Determining whether the master brake cylinder is in an abnormal condition according to the current push rod position and the expected position interval; If so, an alarm is issued to the driver.

5. The method according to any one of claims 1 to 4, characterized in that: Determining the target brake pressure of the brake fluid in the master cylinder according to the displacement and speed of the brake pedal includes: The displacement and speed of the brake pedal are input into a preset displacement-speed-pressure function to obtain the target brake pressure, wherein the displacement-speed-pressure function includes: Among them, P(x,v) represents the hydraulic pressure in the brake master cylinder, x represents the displacement of the brake pedal, v represents the speed of the brake pedal, C1, C2, C3, and C4 are constant coefficients, V0 represents the initial volume of the inner cavity of the brake master cylinder, and A represents the cross-sectional area of ​​the brake master cylinder.

6. The method according to any one of claims 1 to 4, characterized in that: The step of determining the feedforward target position of the master cylinder push rod based on the target brake pressure comprises: The target brake pressure is input into a preset pressure position function to obtain the feedforward target position, wherein the pressure position function includes: Among them, L(P) represents the displacement of the master cylinder push rod, P represents the hydraulic pressure of the brake master cylinder, a, b, c, d, m, f, g, h, i, j are constant coefficients respectively, e is a natural constant, and P1 and P2 are preset pressure thresholds.

7. The method according to any one of claims 1 to 4, characterized in that: The step of determining the feedforward target current of the power-assisting motor according to the final target position includes: The final target position is input into a preset position current function to obtain the feedforward target current, wherein the position current function includes: ； Among them, I(L) represents the feedforward target current, α, β, γ, δ, ϵ, ζ, η, θ, ι, κ, and λ are constant coefficients respectively, L represents the final target position, and L1 and L2 are position segmentation points.

8. An ECU controller, characterized in that: including one or more processors and memory; The memory is coupled to the one or more processors, and the memory is used to store computer program codes, wherein the computer program codes include computer instructions, and the one or more processors call the computer instructions to enable the ECU controller to execute the method according to any one of claims 1 to 7.

9. A computer-readable storage medium storing computer instructions, characterized in that: When the computer instructions are executed on the ECU controller, the ECU controller is caused to execute the method according to any one of claims 1 to 7.

10. A computer program product, characterized in that When the computer program product runs on an ECU controller, the ECU controller is caused to execute the method according to any one of claims 1 to 7.

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