Intelligent control method and system for drum-type cable electronic parking system and electronic device

Abstract

The application discloses a drum cable electronic parking system intelligent control method and system and electronic equipment, based on the motor current characteristics of the cable EPB at the end of release, by real-time monitoring of the current rising trend (including instantaneous value and change rate), the mechanical overshoot risk is dynamically predicted, and the motor target speed is adaptively adjusted, the system kinetic energy is actively inhibited to offset the mechanical inertia, so that the accurate termination of the release action is realized. The method realizes real-time detection and inhibition of cable over-release without increasing additional hardware cost, effectively avoids cable relaxation, clamping response delay and abnormal wear of the mechanical structure in the brake system caused by excessive release stroke, and significantly improves the working reliability of the electronic parking brake and the parking safety level of the vehicle.

Description

Technical Field

[0001] This invention relates to the field of automotive chassis electronic control technology, specifically to an intelligent control method, system, and electronic equipment for a drum-type cable electronic parking system. Background Technology

[0002] With the increasing integration and intelligence of automotive electronic and electrical architectures, the Electronic Parking Brake (EPB) system has become a core component of vehicle safety and driver assistance functions. In drum-type cable EPB systems, the target release position is reached once the brake pads are completely disengaged from the brake drum during release. If the motor continues to operate at this point, it will cause the cable to over-release. This problem is a long-standing and difficult-to-detect latent fault. It not only prolongs the idle travel of subsequent clamping operations and causes a delay in clamping response, but also leads to slow or unstable clamping force establishment, and may even cause irreversible damage and jamming to the internal mechanical structure of the cable. This results in excessive restart current for the motor, seriously affecting braking performance and posing a driving safety hazard.

[0003] Currently, traditional drum-type cable EPB systems mostly employ position control or current control strategies based on fixed thresholds. These strategies are susceptible to interference from environmental factors such as temperature, wear, and lubrication conditions, making it difficult to accurately identify the release endpoint. Furthermore, after reaching the threshold and stopping, the inertia of the transmission system can cause overshoot, still resulting in mechanical shock and structural damage. Simple fixed threshold judgments may lead to insufficient release due to excessive release current in cases of insufficient lubrication or low-temperature jamming, potentially causing brake overheating or burnout during operation. These methods do not adequately consider the dynamic impact of the inertia of the release end mechanism, thus limiting control accuracy and system reliability. Summary of the Invention

[0004] To address the problems existing in the prior art, this invention provides an intelligent control method, system, and electronic equipment for a drum-type cable electronic parking brake system. By analyzing the current changes of the motor during the release process in real time, and combining a lookup table feedforward and proportional-derivative (PD) control fusion strategy, the target speed of the motor is dynamically adjusted, thereby actively suppressing mechanical overshoot and achieving accurate judgment and braking at the release endpoint. This technology effectively solves the problem of decreased braking performance and mechanical damage caused by over-release of drum-type cable EPB, improves system maintainability, and enhances the safety and maintenance economy of the entire vehicle while ensuring braking efficiency.

[0005] Other features and advantages of this application will become apparent from the following detailed description, or may be learned in part from practice of this application.

[0006] According to a first aspect of this application, a smart control method for a drum-type cable electronic parking system is provided, comprising: In response to the EPB cable release command, the operating current of the EPB motor is continuously acquired in real time based on the sensor; A multi-condition release model is established, which includes multiple continuous conditions other than the release start-up stage. The current operating condition of the EPB motor is determined based on the real-time collected operating current, and control commands based on pulse width modulation signals are generated based on the current operating condition. The EPB motor is controlled to rotate based on the control commands, and different operating conditions of the EPB motor are determined based on the real-time collected operating current. Different control commands are executed until the EPB cable is released.

[0007] In some embodiments of this application, based on the aforementioned scheme, the operating current of the EPB motor is continuously and in real-time acquired by a sensor: Based on the continuous real-time acquisition of the analog current signal of the EPB motor by the sensor, after being conditioned by the amplifier circuit, it is sent to the analog-to-digital converter module to be converted into a digital current signal, which is the operating current.

[0008] In some embodiments of this application, based on the aforementioned scheme, the multi-condition release model refers to the operating conditions after the EPB motor completes the release start-up stage, including continuous uniform speed release, dynamic speed regulation, and precise stop conditions. The uniform speed release is the initial stage of EPB motor release, the dynamic speed regulation is the final critical zone of EPB motor release, and the precise stop condition is the boundary of the final critical zone of EPB motor release. In the uniform release condition, the control command is the first rotational speed; In the dynamic speed regulation condition, the second speed is generated by a combination of feedforward lookup table and proportional-derivative control. In the precise stop condition, the control command is the third speed. When it is determined that the EPB motor stroke has reached the critical zone boundary of the release end, the power supply to the EPB motor is cut off or a short-term reverse braking is applied, wherein the first speed > the second speed > the third speed.

[0009] In some embodiments of this application, based on the foregoing scheme, the step of determining the current operating condition of the EPB motor based on the currently collected real-time operating current, and determining the generation of control commands based on pulse width modulation signals based on the current operating condition, includes: When the operating current is less than the first current threshold, the current operating condition of the EPB motor is determined to be the uniform speed release condition. At the instant when the operating current equals the first current threshold, the current operating condition of the EPB motor is determined to change from the uniform speed release condition to the dynamic speed regulation condition. When the operating current is greater than the first current threshold and less than the second current threshold, the current operating condition of the EPB motor is maintained as the dynamic speed regulation condition. The moment the operating current equals the second current threshold, the current operating condition of the EPB motor is determined to change from dynamic speed regulation to precise stop. When the operating current is greater than the second current threshold, the current operating condition of the EPB motor is maintained as precise stop. Here, the first current threshold is less than the second current threshold.

[0010] In some embodiments of this application, based on the aforementioned scheme, the first current threshold is obtained through a pre-calibrated test by averaging the idling current over a preset period, and the calculation formula is as follows:

[0011] in, To calculate the average, For the first The idle current of each cycle The first current threshold, For a preset period; and / or, The second current threshold is obtained by looking up a pre-calibrated two-dimensional table of clamping force and current. The calculation formula is as follows:

[0012] in, The target clamping force of the EPB system on the cable. It is the target current value obtained by looking up the table through the target clamping force. This is the second current threshold.

[0013] In some embodiments of this application, based on the foregoing scheme, the second speed is generated under the dynamic speed regulation condition by a method combining feedforward lookup table and proportional-derivative control, and the calculation formula is as follows:

[0014] in, This is a two-dimensional lookup table function. For the first Operating current per cycle For the first Current growth rate over a period of time The first current threshold, This is the proportional gain coefficient. The differential gain coefficient, This is the second rotational speed.

[0015] In some embodiments of this application, based on the foregoing scheme, the method for obtaining the third rotational speed is as follows: The estimated rotational speed is obtained using the following formula:

[0016] in, For the first Estimated EPB motor speed over one cycle, For the first EPB motor voltage collected in each cycle For the first Operating current per cycle For the armature resistance of the EPB motor, Let EPB be the back electromotive force constant of the motor; If the estimated rotational speed is less than the preset safe shutdown rotational speed, the estimated rotational speed shall be used as the third rotational speed; If the estimated rotational speed is greater than or equal to the preset safe shutdown rotational speed, the safe shutdown rotational speed shall be used as the third rotational speed.

[0017] In some embodiments of this application, based on the aforementioned scheme, at the vehicle wheel end, the EPB motor includes a left EPB motor and a right EPB motor. The left and right EPB motors respectively drive the left and right cables. A first current sensor continuously acquires the operating current of the left EPB motor in real time to control the left EPB motor and release the left cable. A second current sensor continuously acquires the operating current of the right EPB motor in real time to control the right EPB motor and release the right cable; or... At the vehicle wheel end, an EPB motor simultaneously drives both the left and right stay cables. A current sensor continuously monitors the operating current of the drum motor in real time, controlling the EPB motor to simultaneously release both the left and right stay cables; or, At the end of the vehicle axle, a central EPB motor is used to drive a central cable to tighten the parking brake mechanism at the rear axle end of the vehicle to complete parking. The operating current of the central EPB motor is continuously acquired in real time by a current sensor, and the central EPB motor is controlled to release the central cable.

[0018] According to a second aspect of this application, an intelligent control system for a drum-type cable electronic parking system is provided, comprising: The data acquisition module is used to continuously acquire the operating current of the EPB motor based on sensors when the EPB cable executes the release command. The motor control command generation module is used to realize differentiated control of the multi-condition release model. The multi-condition release model includes multiple continuous conditions other than the release start-up stage. The current condition of the EPB motor is determined based on the real-time collected operating current, and control commands based on pulse width modulation signals are generated based on the current condition. The motor control module is used to execute the control commands to drive the EPB cable motor to rotate, and then to determine the different operating conditions of the EPB motor based on the real-time collected operating current, and execute different control commands until the EPB cable is released.

[0019] According to a third aspect of this application, an electronic device is provided, comprising: Sensors are used to continuously acquire the operating current of the EPB motor in real time; The processor, electrically connected to the sensor, is used to execute executable instructions, which are: establishing a multi-condition release model, the multi-condition release model including multiple consecutive conditions other than the release start-up stage; determining the current condition of the EPB motor based on the currently collected real-time operating current; and generating control instructions based on pulse width modulation signals based on the current condition. The power drive module is used to receive control commands and control the rotation of the EPB motor; The memory is used to store the executable instructions of the processor and to perform high-speed data interaction with the memory through a synchronous serial peripheral interface. When the executable instructions are executed by the processor, the processor implements the above-described method. A power supply module is used to supply power to the sensor, processor, power drive module and memory. The processor controls the power supply module to provide a stable voltage output through hardwired instructions and SPI protocol.

[0020] The beneficial effects of this application are as follows: This application provides an intelligent control method, system, and electronic device for a drum-type cable electronic parking brake (EPB) system. During the release process of the EPB cable, based on the current characteristics of the EPB motor, and addressing the overshoot phenomenon caused by the inertia of the transmission system, a three-stage speed control mechanism is formed by integrating calibration parameter feedforward lookup table and proportional-derivative control strategy. This application actively suppresses mechanical overshoot by dynamically adjusting the speed of the EPB motor, achieving precise identification of the release stroke end point and accurate control of the braking timing. This effectively solves the problems of parking brake performance degradation and mechanical structural damage caused by excessive cable release, ensuring that the braking system remains in optimal working condition and significantly improving vehicle parking safety and operational reliability. This application can be implemented entirely based on the existing hardware architecture of the EPB system without incurring additional costs. Optionally, this anti-over-release function can also be integrated into the vehicle's ABS, ESC, or other electronic control units, helping to further improve the integration and lightweighting of the vehicle controller.

[0021] It should be understood that the above general description and the following detailed description are merely exemplary and explanatory, and do not limit this application. Attached Figure Description

[0022] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and are intended to explain the invention, but do not constitute an undue limitation thereof. In the drawings: Figure 1This is a flowchart of an intelligent control method for a drum-type cable electronic parking system according to the present invention; Figure 2 This is a schematic diagram of the mechanical structure of the drum-type cable EPB in an embodiment of the present invention; Figure 3 This is a detailed schematic diagram of the EPB motor control of the present invention; Figure 4 This is a schematic diagram of an intelligent control system for a drum-type cable electronic parking system according to the present invention; Figure 5 This is a schematic diagram of an electronic device according to the present invention. Detailed Implementation

[0023] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0024] It should be understood that the terms "comprising" and other similar expressions in the specification, claims, and accompanying drawings of this invention are intended to cover a non-exclusive inclusion, such as a process, method, system, or apparatus that includes a series of steps or units and is not limited to the listed steps or units. Furthermore, "first" and "second" are used to distinguish different objects and are not intended to describe a specific order.

[0025] The mechanical structure of the drum cable EPB is as follows: Figure 2 As shown, the device includes a motor axial worm gear 1, a cable axial turbine 2, a cable axial worm gear 3, a mechanical housing 4, and a shock-absorbing disc spring 5. The motor axial worm gear 1 meshes with the cable axial turbine 2 in a perpendicular direction; the cable axial turbine 2 and the cable axial worm gear 3 have their axes coincident and are internally meshed. One end of the cable axial worm gear 3 is connected to the EPB cable, and a shock-absorbing disc spring 5 is installed between the cable axial turbine 2 and the mechanical housing 4 to buffer the impact during the transmission process.

[0026] During the release process of the EPB cable, the EPB motor drives the axial worm gear 1 to rotate, which in turn drives the axial turbine gear 2 of the cable to rotate, thereby causing the axial worm gear 3 of the cable to move downward along the axial direction, compressing the damping disc spring 5. If the EPB motor continues to rotate due to inertia after the axial worm gear 3 of the cable reaches a preset threshold distance while running at a constant speed, it will lead to over-release, causing the damping disc spring 5 to be over-compressed. At this time, the rebound force generated by the damping disc spring 5 will significantly increase the frictional resistance between the axial turbine gear 2 and the axial worm gear 3 of the cable, thereby causing the transmission mechanism to jam. If this continues for a long time, it may cause irreversible plastic deformation of the damping disc spring 5, causing permanent damage to the mechanical structure of the drum cable EPB, and significantly reducing the life of the drum cable EPB.

[0027] According to the first aspect of this application, in order to address the shortcomings of the prior art, such as Figure 1 As shown, this embodiment provides an intelligent control method for a drum-type cable electronic parking system, including: Step S101: In response to the EPB cable release command, continuously acquire the operating current of the EPB motor based on the sensor in real time.

[0028] In one embodiment, at the wheel end of the vehicle, the vehicle is typically equipped with a left EPB motor and a right EPB motor, which drive the left cable and the right cable respectively. This embodiment includes a sensor group comprising a first current sensor and a second current sensor.

[0029] The first current sensor collects the analog current signal of the left EPB motor, and then continuously acquires the operating current of the left EPB motor in real time to control the left EPB motor and release the left cable.

[0030] The second current sensor collects the analog current signal of the right EPB motor, and then continuously acquires the operating current of the right EPB motor in real time to control the right EPB motor and release the right cable.

[0031] In another embodiment, at the wheel end of the vehicle, an EPB motor is used to drive both the left and right cables simultaneously. The operating current of the drum motor is continuously acquired in real time by a current sensor, and the EPB motor is controlled to release both the left and right cables at the same time.

[0032] Alternatively, in another embodiment, a central EPB motor is used to drive a central cable to tighten the parking brake mechanism at the rear axle end of the vehicle, thereby completing parking. The operating current of the central EPB motor is continuously acquired in real time by a current sensor, and the central EPB motor is controlled to release the central cable.

[0033] In some embodiments of this example, the step of continuously acquiring the operating current of the EPB motor based on sensors in real time is as follows: Based on the continuous real-time acquisition of the analog current signal of the EPB motor by the sensor, after being conditioned by the amplifier circuit, it is sent to the analog-to-digital converter (ADC) module to be converted into a digital current signal, which is the operating current.

[0034] In this embodiment, the method also includes filtering the operating current and extracting the stable value and current growth rate of the operating current to enable subsequent determination of the current operating condition of the EPB motor.

[0035] Due to the inherent electrical characteristics of the sensor and disturbances caused by changes in non-vehicle conditions, a significant amount of noise is present in the generated operating current. Since the intelligent control algorithm for preventing over-release requires high precision and real-time performance, the signal's anti-interference capability must be considered. This necessitates optimizing the signal processing algorithm through outlier removal, smoothing, and filtering to produce a low-noise signal suitable for input. As an alternative implementation, this embodiment uses a moving average filter to process the original input signal matrix. This filter efficiently filters high-frequency noise and exhibits excellent step response characteristics. Alternatively, in other embodiments, a second-order low-pass filter can be used to selectively set the filtering frequency of the original signal to remove high-frequency noise. Therefore, this embodiment merely demonstrates the selectivity of the filter and is not intended to limit the scope of this patent application.

[0036] Step S102: Establish a multi-condition release model, which includes multiple continuous conditions other than the release start-up stage. Determine the current condition of the EPB motor based on the real-time collected operating current, and generate control commands based on pulse width modulation signals based on the current condition to dynamically adjust the speed of the EPB motor and suppress mechanical overshoot.

[0037] In some implementations of this embodiment, such as Figure 3 As shown, the multi-condition release model adopts a three-stage control strategy during the release process, including continuous uniform speed release condition, dynamic speed regulation condition and precise stop condition. The uniform speed release condition is the initial stage of EPB motor release, the dynamic speed regulation condition is the final critical zone of EPB motor release, and the precise stop condition is the boundary of the final critical zone of EPB motor release. In the uniform release condition, the control command is a first rotational speed based on a pulse width modulation (PWM) signal with a constant duty cycle; In the dynamic speed regulation condition, the second speed is generated by a combination of feedforward lookup table and proportional-derivative control. In the precise stop condition, the control command is a third speed based on a pulse width modulation (PWM) signal with a constant duty cycle, which controls the EPB motor to brake and stop precisely. When it is determined that the EPB motor stroke has reached the critical zone boundary of the release end, the power supply to the EPB motor is cut off or a reverse short-term braking is applied, wherein the first speed > the second speed > the third speed.

[0038] In some implementations of this embodiment, such as Figure 3 As shown, the step of determining the current operating condition of the EPB motor based on the currently collected real-time operating current, and generating control commands based on pulse width modulation signals based on the current operating condition, includes: When the operating current is less than the first current threshold or the current growth rate of the operating current is less than the first growth rate threshold, the current operating condition of the EPB motor is determined to be the uniform speed release condition. At this time, the EPB motor is controlled to run at a uniform speed of the first speed. In order to improve the release efficiency, the processor outputs a high PWM signal with a constant duty cycle to control the motor to run at a high first speed, so that the release stroke quickly approaches the end critical zone of the release. When the operating current equals the first current threshold or the current growth rate of the operating current equals the first growth rate threshold, the current operating condition of the EPB motor is determined to change from the uniform speed release condition to the dynamic speed regulation condition. When the operating current is greater than the first current threshold and less than the second current threshold, or the current growth rate of the operating current is greater than the first growth rate threshold and less than the second growth rate threshold, the current operating condition of the EPB motor is determined to be the dynamic speed regulation condition. The moment the operating current equals the second current threshold, the current operating condition of the EPB motor is determined to change from dynamic speed regulation to precise stop. When the operating current is greater than the first current threshold, or the current growth rate of the operating current is greater than the second growth rate threshold, the current operating condition of the EPB motor is determined to be precise stop. Here, the first current threshold is less than the second current threshold, and the first growth rate threshold is greater than the second growth rate threshold.

[0039] In some embodiments of this example, the first current threshold is obtained by averaging the idling current of a preset period during the clamping process of the EPB motor. The calculation formula is as follows:

[0040] in, To calculate the average, For the first The idle current of each cycle The first current threshold, For preset period; And / or, The second current threshold is obtained by looking up a pre-calibrated two-dimensional table of clamping force and current. The calculation formula is as follows:

[0041] in, The target clamping force of the EPB system on the cable. It is the target current value obtained by looking up the table through the target clamping force. This is the second current threshold.

[0042] In some embodiments of this example, a first rotational speed is preset, and the first rotational speed is converted into a first target voltage or a first pulse width modulation signal to control the EPB motor to rotate at the first rotational speed.

[0043] Specifically, the first speed is set by directly setting a PWM with a large duty cycle, such as PWM>80%.

[0044] In some embodiments of this example, to suppress mechanical impact caused by high-speed motion, the calculation formula for the method combining feedforward lookup table and proportional-derivative control is as follows:

[0045] in, This is a two-dimensional lookup table function. For the first Operating current per cycle For the first Current growth rate over a period of time The first current threshold, This is the proportional gain coefficient. The differential gain coefficient, This is the second rotational speed.

[0046] In the formula, the operating current is collected in real time. and current growth rate By querying a pre-calibrated two-dimensional mapping table, the optimal feedforward quantity under the current operating condition is obtained to improve the response speed of the closed-loop system; simultaneously, the current deviation is used as the basis for further analysis. As a proportional term, the current growth rate As a differential term, combined with the proportional gain coefficient and differential gain coefficient The optimal speed command for the current-speed closed loop in the second release stage is calculated in real time.

[0047] The second rotational speed is converted into a second target voltage or a second pulse width modulation signal to control the EPB motor to rotate at the second rotational speed.

[0048] In some embodiments of this example, the method for obtaining the third rotational speed is as follows: The estimated rotational speed is obtained using the following formula:

[0049] in, For the first Estimated EPB motor speed over one cycle, For the first EPB motor voltage collected in each cycle For the first Operating current per cycle For the armature resistance of the EPB motor, Let EPB be the back electromotive force constant of the motor; If the estimated rotational speed is less than the preset safe shutdown rotational speed, the estimated rotational speed shall be used as the third rotational speed; If the estimated rotational speed is greater than or equal to the preset safe shutdown rotational speed, the safe shutdown rotational speed shall be used as the third rotational speed.

[0050] When it is determined that the EPB motor travel has reached the critical zone boundary of the release end, the power supply to the EPB motor is cut off or a short-term reverse braking is applied.

[0051] Step S103: Control the EPB motor to rotate based on the control command, and then determine the different operating conditions of the EPB motor according to the real-time collected operating current, and execute different control commands until the EPB cable is released.

[0052] Thus, during the release process of the EPB cable, based on the current characteristics of the EPB motor, and addressing the overshoot phenomenon caused by the inertia of the transmission system, a three-stage speed control mechanism is formed by integrating calibration parameter feedforward lookup table and proportional-derivative control strategy. This method actively suppresses mechanical overshoot by dynamically adjusting the speed of the EPB motor, achieving precise identification of the release stroke end point and accurate control of braking timing. It effectively solves the problems of parking brake performance degradation and mechanical structural damage caused by excessive cable release, ensuring the braking system remains in optimal working condition and significantly improving vehicle parking safety and operational reliability.

[0053] This method can be implemented entirely based on the existing hardware architecture of the EPB system without incurring additional costs. Optionally, this over-release protection function can also be integrated into the vehicle's ABS, ESC, or other electronic control units, which helps to further improve the integration and weight reduction of the vehicle controller.

[0054] According to the second aspect of this application, such as Figure 4 As shown in the figure, the intelligent control system for a drum-type cable electronic parking system provided in this embodiment includes: The data acquisition module is used to continuously acquire the operating current of the EPB motor based on sensors when the EPB cable executes the release command. The control command generation module is used to realize differentiated control of the multi-condition release model. The multi-condition release model includes multiple continuous conditions other than the release start-up stage. The current condition of the EPB motor is determined based on the real-time collected operating current, and control commands based on pulse width modulation signals are generated based on the current condition. The motor control module is used to execute the control commands to drive the EPB cable motor to rotate, and then to determine the different operating conditions of the EPB motor based on the real-time collected operating current, and execute different control commands until the EPB cable is released.

[0055] Specifically, this embodiment corresponds one-to-one with the above method embodiments. The functions of each module have been described in detail in the corresponding method embodiments, so they will not be repeated here.

[0056] According to a third aspect of this application, this embodiment provides a computer-readable storage medium having a computer program stored thereon, the computer program including executable instructions that, when executed by a processor, implement the method described above.

[0057] The present invention can implement all or part of the processes in the above methods, or it can be accomplished by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when the computer program is executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable file, or some intermediate form. The computer-readable medium can include: any entity or system capable of carrying computer program code, recording media, USB flash drive, portable hard drive, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0058] According to the fourth aspect of this application, such as Figure 5 As shown, an electronic device is provided, which is the hardware architecture upon which the intelligent control method for a drum-type cable electronic parking system provided in this embodiment relies, including: Sensors are used to continuously acquire the operating current of the EPB motor in real time; The processor, electrically connected to the sensor, is used to execute executable instructions, which are: establishing a multi-condition release model, the multi-condition release model including multiple consecutive conditions, determining the current condition of the EPB motor based on the current real-time collected operating current, and generating control instructions based on pulse width modulation (PWM) signals based on the condition. The power drive module is used to receive control commands and control the rotation of the EPB motor to ensure a smooth and controllable EPB cable release process. The memory is used to store the executable instructions and parameters of the processor, ensuring the continuity of the control logic and the reliable recovery of the EPB motor state during the power cycle. It interacts with the memory at high speed through a synchronous serial peripheral interface (SPI). When the executable instructions are executed by the processor, the processor implements the above-mentioned method. The power supply module is used to supply power to the sensor, processor, power drive module and memory to provide a stable and isolated power output. The processor controls the power supply module to provide a stable voltage output through hard-wired instructions and SPI (Serial Peripheral Interface) protocol.

[0059] In one specific embodiment, the processor model is SAK-XC2365B. The processor's basic configuration includes: system clock, phase-locked loop, watchdog timer, etc. The functional module initialization configuration includes: timer (TIM) module, pulse width modulation (PWM) module, analog signal acquisition module, CAN communication module, etc. The application layer software initialization configuration includes: setting the system status and fault codes to safe default values, loading calibration data and key control parameters, starting self-test program and diagnostics, etc.

[0060] Its working principle is as follows: In response to the EPB cable release command, the left / right EPB motors are sampled at high frequency by two onboard current sensors to obtain analog current signals. After being conditioned by an amplifier circuit, the analog current signals are sent to the processor's analog-to-digital converter module to obtain digital current signals. The digital current signals serve as the core input signals for the control algorithm. After filtering the digital current signals, the processor analyzes the real-time current characteristics of the EPB motors during the release process, thereby accurately identifying the specific operating condition of the cable actuator. After completing the operating condition identification, the algorithm is based on a feedforward lookup table and proportional... The strategy of integrating differential (PD) control calculates the optimal speed of the EPB motor in real time and executes a three-stage speed regulation mechanism. Finally, the processor outputs the corresponding pulse width modulation (PWM) signal to precisely control the operation of the EPB motor, actively suppress the inertia of the transmission mechanism, achieve precise control of the cable release stroke, and ensure that the motor brakes reliably at the target position.

[0061] In this embodiment, the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor. The processor is the control center of the computer system, connecting various parts of the entire computer system through various interfaces and lines.

[0062] Memory can be used to store computer programs and / or modules. The processor implements various functions of the computer system by running or executing the computer programs and / or modules stored in the memory, and by accessing data stored in the memory. Memory can mainly include a program storage area and a data storage area. The program storage area can store the operating system and at least one application program required for a function (e.g., sound playback, image playback, etc.); the data storage area can store data created based on the use of the mobile phone (e.g., audio data, video data, etc.). Furthermore, memory can include high-speed random access memory, and can also include non-volatile memory, such as hard disks, RAM, plug-in hard disks, SmartMedia Cards (SMC), Secure Digital (SD) cards, Flash Cards, at least one disk storage device, flash memory device, or other volatile solid-state storage devices.

[0063] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, servers, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage and memory) containing computer-usable program code.

[0064] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), servers, and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A system that specifies functions in one or more boxes.

[0065] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including an instruction set implemented in a process. Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0066] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0067] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0068] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0069] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. 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. Such 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.

Claims

1. A method for intelligent control of a drum-type cable electronic parking system, characterized in that, include: In response to the EPB cable release command, the operating current of the EPB motor is continuously acquired in real time based on the sensor; A multi-condition release model is established, which includes multiple continuous conditions excluding the release start-up phase. The current operating condition of the EPB motor is determined based on the currently collected real-time operating current. Based on the current operating condition, a control command based on pulse width modulation (PWM) signals is generated. The multi-condition release model refers to the operating conditions after the EPB motor completes the release start-up phase. The multiple continuous operating conditions include continuous uniform speed release, dynamic speed regulation, and precise stop conditions. The uniform speed release is the initial stage of EPB motor release; the dynamic speed regulation is the final critical zone of EPB motor release; and the precise stop condition is the boundary of the final critical zone of EPB motor release. Specifically: When the operating current is less than the first current threshold, the current operating condition of the EPB motor is determined to be the uniform speed release condition. At the instant when the operating current equals the first current threshold, the current operating condition of the EPB motor is determined to change from the uniform speed release condition to the dynamic speed regulation condition. When the operating current is greater than the first current threshold and less than the second current threshold, the current operating condition of the EPB motor is maintained as the dynamic speed regulation condition. When the operating current equals the second current threshold, the current operating condition of the EPB motor is determined to change from dynamic speed regulation to precise stop. When the operating current is greater than the second current threshold, the current operating condition of the EPB motor is maintained as precise stop. Here, the first current threshold is less than the second current threshold. In the uniform release condition, the control command is the first rotational speed; In the dynamic speed regulation condition, the second speed is generated by a combination of feedforward lookup table and proportional-derivative control. In the precise stop condition, the control command is the third speed. When it is determined that the EPB motor stroke has reached the critical zone boundary of the release end, the power supply to the EPB motor is cut off or a short-term reverse braking is applied. Among them, the first speed > the second speed > the third speed. The EPB motor is controlled to rotate based on the control commands, and different operating conditions of the EPB motor are determined based on the real-time collected operating current. Different control commands are executed until the EPB cable is released.

2. The method according to claim 1, characterized in that, The operating current of the EPB motor is continuously and in real time acquired based on sensors. Based on the continuous real-time acquisition of the analog current signal of the EPB motor by the sensor, after being conditioned by the amplifier circuit, it is sent to the analog-to-digital converter module to be converted into a digital current signal, which is the operating current.

3. The method according to claim 1, characterized in that: The first current threshold is obtained through a pre-calibrated test by averaging the idling current over a preset period. The calculation formula is as follows: in, To calculate the average, For the first The idle current of each cycle The first current threshold, For a preset period; and / or, The second current threshold is obtained by looking up a pre-calibrated two-dimensional table of clamping force and current. The calculation formula is as follows: in, The target clamping force of the EPB system on the cable. It is the target current value obtained by looking up the target clamping force in a table. This is the second current threshold.

4. The method according to claim 1, characterized in that, In the dynamic speed regulation condition, the second speed is generated by a combination of feedforward lookup table and proportional-derivative control, and the calculation formula is as follows: in, This is a two-dimensional lookup table function. For the first Operating current per cycle For the first Current growth rate over a period of time The first current threshold, This is the proportional gain coefficient. The differential gain coefficient, This is the second rotational speed.

5. The method according to claim 1, characterized in that, The method for obtaining the third rotational speed is as follows: The estimated rotational speed is obtained using the following formula: in, For the first Estimated EPB motor speed over one cycle, For the first EPB motor voltage collected in each cycle For the first Operating current per cycle For the armature resistance of the EPB motor, Let EPB be the back electromotive force constant of the motor; If the estimated rotational speed is less than the preset safe shutdown rotational speed, the estimated rotational speed shall be used as the third rotational speed; If the estimated rotational speed is greater than or equal to the preset safe shutdown rotational speed, the safe shutdown rotational speed shall be used as the third rotational speed.

6. The method according to claim 1, characterized in that: At the vehicle wheel end, the EPB motor includes a left EPB motor and a right EPB motor. The left EPB motor and the right EPB motor drive the left cable and the right cable respectively. The operating current of the left EPB motor is continuously acquired in real time through a first current sensor, and the left EPB motor is controlled to release the left cable. The operating current of the right EPB motor is continuously acquired in real time through a second current sensor, and the right EPB motor is controlled to release the right cable. or, At the vehicle wheel end, an EPB motor simultaneously drives both the left and right stay cables. A current sensor continuously monitors the operating current of the drum motor in real time, controlling the EPB motor to simultaneously release both the left and right stay cables; or, At the end of the vehicle axle, a central EPB motor is used to drive a central cable to tighten the parking brake mechanism at the rear axle end of the vehicle to complete parking. The operating current of the central EPB motor is continuously acquired in real time by a current sensor, and the central EPB motor is controlled to release the central cable.

7. An intelligent control system for a drum-type cable electronic parking system, applied to the intelligent control method for the drum-type cable electronic parking system according to any one of claims 1-6, characterized in that, include: The data acquisition module is used to continuously acquire the operating current of the EPB motor based on sensors when the EPB cable executes the release command. The control command generation module is used to realize differentiated control of the multi-condition release model. The multi-condition release model includes multiple continuous conditions other than the release start-up stage. The current condition of the EPB motor is determined based on the real-time collected operating current, and control commands based on pulse width modulation signals are generated based on the current condition. The motor control module is used to execute the control commands to drive the EPB motor to rotate, and then to determine the different operating conditions of the EPB motor based on the real-time collected operating current, and execute different control commands until the EPB cable is released.

8. An electronic device, characterized in that, include: Sensors are used to continuously acquire the operating current of the EPB motor in real time; The processor, electrically connected to the sensor, is used to execute executable instructions, which are: establishing a multi-condition release model, the multi-condition release model including multiple consecutive conditions other than the release start-up stage; determining the current condition of the EPB motor based on the currently collected real-time operating current; and generating control instructions based on pulse width modulation signals based on the current condition. The power drive module is used to receive control commands and control the rotation of the EPB motor; The memory is used to store the executable instructions of the processor, and to perform high-speed data interaction with the memory through a synchronous serial peripheral interface. When the executable instructions are executed by the processor, the processor enables the processor to implement the method described in any one of claims 1-5. A power supply module is used to supply power to the sensor, processor, power drive module and memory. The processor controls the power supply module to provide a stable voltage output through hardwired instructions and SPI protocol.

Images