Electro-mechanical braking system and electric vehicle
Patent Information
- Application Number
- PCT/CN2026/087558
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2025-04-18
- Filing Date
- 2026-03-31
- Publication Date
- 2026-10-22
Smart Images
Figure CN2026087558_22102026_PF_FP_ABST
Abstract
Description
Electromechanical braking systems and electric vehicles
[0001] This application claims priority to Chinese Patent Application No. 202510495821.5, filed on April 18, 2025, entitled "Electromechanical Braking System and Electric Vehicle", the entire contents of which are incorporated herein by reference. Technical Field
[0002] This application relates to the field of vehicles, and more particularly to an electromechanical braking system and an electric vehicle. Background Technology
[0003] With the widespread adoption of automobiles, the requirements for vehicle safety are increasing daily. Vehicle braking systems have always played a crucial role in vehicle safety, and with the rapid development of automotive technology and the continuous increase in vehicle speeds, their importance has become increasingly apparent. Electromechanical braking (EMB) systems offer advantages such as fast response and high efficiency, better meeting the evolving needs of automobiles in terms of safety and efficiency, especially adapting to the electrification of vehicles. However, current EMB systems typically require at least one central controller to identify braking demand and distribute braking torque, resulting in higher system complexity and cost. Summary of the Invention
[0004] This application provides an electromechanical braking system and an electric vehicle. By connecting the brake pedal sensor signal to a wheel-end braking device, the wheel-end control device can perform braking control based on the brake pedal opening, which simplifies the structure of the braking system while ensuring the braking performance of the electromechanical braking system.
[0005] In a first aspect, an electromechanical braking system is provided, comprising four wheel-end braking devices, each wheel-end braking device including a wheel-end controller and a brake, each wheel-end controller controlling the brake to output braking force. The housing surface of the first wheel-end controller of the four wheel-end braking devices includes a brake pedal sensor interface and a control interface. The brake pedal sensor interface is used to connect to a brake pedal sensor of the electric vehicle, and the control interface is used to connect to the other three wheel-end controllers. The first wheel-end controller controls the brakes of the four wheel-end braking devices to brake the four wheels of the electric vehicle according to the brake pedal opening indicated by the brake pedal sensor.
[0006] It is understood that the wheel-end controller used to connect to the brake pedal sensor among the four wheel-end controllers provided in this application embodiment is the first wheel-end controller. In other words, the first wheel-end controller refers to the wheel-end controller connected to the brake pedal sensor, and does not specifically refer to one of the four wheel-end controllers, but can be any one of the four wheel-end controllers.
[0007] The brake pedal sensor can be of different types, such as a brake pedal displacement sensor or a brake pedal pressure sensor, and this application embodiment is not limited to these types. The brake pedal displacement sensor monitors the movement angle of the brake pedal. The first wheel-end controller can calculate the brake pedal travel or opening based on the brake pedal travel angle from the brake pedal sensor to obtain the braking force requirement of the electric vehicle. The brake pedal pressure sensor monitors the pressure acting on the brake pedal. The first wheel-end controller can calculate the braking travel or opening based on the pressure acting on the brake pedal to obtain the braking force requirement of the electric vehicle.
[0008] The first wheel-end controller connects to the brake pedal sensor via a brake pedal sensor interface. This allows the control circuit within the first wheel-end controller to receive brake pedal signals from the sensor through the interface and internal wiring, and then identify the required braking force based on these signals. The brake pedal opening indicates the driver's required braking force; a larger opening indicates a greater braking demand, requiring a larger braking force from the braking system. During normal vehicle operation, the first wheel-end controller controls the wheel-end braking device to output the braking force indicated by the brake pedal opening. A larger opening requires a larger braking force, and a smaller opening requires a smaller braking force. In other words, the braking force output by the wheel-end braking device changes with the brake pedal opening.
[0009] Furthermore, the first wheel-end controller is connected to the other three wheel-end controllers through a control interface on the surface of the housing, so that the control circuit in the first wheel-end controller can send control signals to some or all of the other three wheel-end controllers through the control interface, thereby controlling the corresponding brake to output braking force.
[0010] In other words, after determining the required braking force of the four brakes based on the brake pedal opening, the first wheel-end controller can control the braking torque output by the brake motor to the actuator without needing to distribute the braking force through the central controller. Simultaneously, the first wheel-end controller can also output braking control signals to some or all of the other three wheel-end controllers via a control interface. These braking control signals indicate the required braking force for the brake corresponding to the receiving wheel-end controller.
[0011] According to the present application, the signal of the brake pedal sensor is connected to the wheel end controller of a wheel end braking device. The wheel end controller identifies the braking demand and distributes the braking force based on the brake pedal sensor signal, which simplifies the structure of the braking system while ensuring the braking performance of the electromechanical braking system.
[0012] In conjunction with the first aspect, in some implementations, the electromechanical braking system further includes a central controller for receiving brake pedal signals from another brake pedal sensor, and the control interface is also used to connect to the central controller. In response to the central controller being active, the first wheel-end controller is further configured to control the corresponding brake to output braking force according to the braking control signal from the central controller. In response to the central controller being inactive, the first wheel-end controller is further configured to control the brakes in the four wheel-end braking devices to brake the four wheels of the electric vehicle according to the brake pedal opening indicated by the brake pedal sensor.
[0013] It is understandable that the central controller can serve as the main controller in an electromechanical braking system. When the central controller is active, the first wheel-end controller can act as an actuator, controlling the corresponding brake to output braking force according to the braking control signal from the central controller.
[0014] It is understood that when the central controller fails, the first wheel-end controller, acting as the computing center, controls the brakes in the four wheel-end braking devices to output braking force to the wheels of the electric vehicle based on the brake pedal opening indicated by the brake pedal sensor. This application does not limit the specific method by which the first wheel-end controller determines the failure of the central controller. For example, the signals interacting between the central controller and the four wheel-end controllers may include a central controller validity bit signal, which indicates whether the central controller is valid or invalid. Furthermore, the central controller sends the central controller validity bit signal to the four wheel-end controllers, allowing them to obtain the current validity status of the central controller. For example, when the central controller fails, it loses the ability to communicate with the four wheel-end controllers. That is, when the four wheel-end controllers cannot receive signals from the central controller, they determine that the central controller has failed.
[0015] According to the present application, the first wheel-end controller can serve as a redundant controller in the electromechanical braking system, so as to continue to control the brakes in the four wheel-end braking devices to output braking force when the central controller fails, thereby avoiding the failure of the entire electromechanical braking system due to the failure of the central controller and improving the safety and reliability of the braking system.
[0016] In conjunction with the first aspect, in some implementations, the brake pedal sensor interface is used to receive at least two brake pedal signals from the brake pedal sensor, and the central controller is used to receive at least two brake pedal signals from the other brake pedal sensor.
[0017] According to the present application, the electromechanical braking system provided includes two brake pedal sensors that serve as backups for each other. These two sensors are respectively connected to the central controller and the first wheel-end controller. On the one hand, the two brake pedal sensors can more accurately detect the movement state of the brake pedal; on the other hand, if one brake pedal sensor fails, the other brake pedal sensor can still independently detect the movement state of the brake pedal, thus improving the operational reliability of the electromechanical braking system.
[0018] In conjunction with the first aspect, in some implementations, the first wheel-end controller is also used to output at least two brake pedal signals from the brake pedal sensor to the central controller via the control interface.
[0019] It is understood that the first wheel-end controller may directly output the received signal to the central controller when it receives at least two brake pedal signals from the brake pedal sensor, or it may output the received signal to the first wheel-end controller in response to a signal from the central controller indicating that the brake sensor has failed. This application embodiment does not limit this.
[0020] According to the present application, the central controller can receive brake pedal signals from the brake pedal sensor through the first wheel-end controller, so that even if the other connected brake pedal sensor fails, the central controller can still control the four wheel-end braking devices to output the braking force corresponding to the brake pedal opening based on the brake pedal opening indicated by the brake pedal signal.
[0021] In conjunction with the first aspect, in some implementations, the housing of the first wheel-end controller further includes a first communication interface. The first wheel-end controller is also used to receive an accelerator pedal signal from the vehicle controller via the first communication interface. This accelerator pedal signal indicates the opening degree of the accelerator pedal of the electric vehicle. In response to the failure of both the brake pedal sensor and the other brake pedal sensor, and a decrease in the accelerator pedal opening indicated by the accelerator pedal signal, the first wheel-end controller is further used to control the brakes of the four wheel-end braking devices to output braking force to the four wheels of the electric vehicle. This braking force increases as the accelerator pedal opening decreases.
[0022] It is understandable that if the brake pedal sensor and another brake pedal sensor both fail, and the accelerator pedal sensor indicates a decrease in the accelerator pedal opening, this can be interpreted as the driver beginning to release the accelerator pedal. At this point, the first wheel-end controller can control the brakes in the four wheel-end braking devices to output braking force, thereby assisting the electric vehicle to gradually decelerate until it comes to a stop. In other words, even if the brake pedal sensor of the electric vehicle fails, the driver can control the four wheel-end braking devices to brake the four wheels of the electric vehicle by operating the accelerator pedal.
[0023] According to the solution in this application, in the scenario where all brake pedal sensors in an electric vehicle fail, the first wheel-end controller can still control the output braking force of the four wheel-end devices based on the degree of reduction in the accelerator pedal opening, thereby avoiding the risk of brake failure caused by brake pedal sensor failure and improving the safety and reliability of electric vehicles.
[0024] In conjunction with the first aspect, in some implementations, the first wheel-end controller is also configured to receive at least one accelerator pedal signal from the accelerator pedal sensor of the electric vehicle via the first communication interface.
[0025] It is understandable that even if both the brake pedal sensor and another brake pedal sensor fail, and the vehicle controller malfunctions or the connection with the vehicle controller fails, the first wheel-end controller can still control the four brakes to output braking force to the four wheels based on the accelerator pedal opening by using the accelerator pedal signal obtained from the accelerator pedal sensor.
[0026] It is understood that the signals output by the sensors in this application, such as accelerator pedal signals and brake pedal signals, are single-edge nibble transmission (SENT) signals, or analog voltage signals, or analog current signals, etc.
[0027] According to the present application, the first wheel end controller can acquire multiple signals from the accelerator pedal sensor to achieve signal redundancy, which can further improve the reliability and safety of the electromechanical braking system.
[0028] In conjunction with the first aspect, in some implementations, in response to the failure of the accelerator pedal signal, the first wheel-end controller is also used to control the brakes of the four wheel-end braking devices to output a preset braking force to the brakes of the four wheels of the electric vehicle.
[0029] It is understandable that during the operation of an electric vehicle, a failure of the accelerator pedal signal can cause the electric vehicle's drive system to be unable to output torque based on the accurate accelerator pedal opening, resulting in uncontrolled power output. In this situation, to prevent the driver from being unable to make timely and correct adjustments due to interference with driving confidence, the first wheel-end controller actively controls the brakes of the four wheel-end braking devices to output a preset braking force, causing the electric vehicle to gradually decelerate until it comes to a complete stop, thus ensuring the driving safety of the electric vehicle. Active control means that the first wheel-end controller can control the braking force output of the four wheel-end braking devices in response to the failure of the accelerator pedal sensor, without relying on changes in the brake pedal opening indicated by the brake pedal sensor or the braking control signal from the central controller.
[0030] Furthermore, when the brake pedal sensor is active, the first wheel-end controller can also adjust the braking force output by the brakes in the four wheel-end braking devices in response to changes in the brake pedal opening indicated by the brake pedal sensor during the output of the preset braking force.
[0031] According to the present application, the first wheel-end controller can actively control the braking devices of the four wheels to output braking force when the accelerator pedal sensor fails, thereby actively reducing the vehicle speed and ensuring the driving safety of the electric vehicle.
[0032] In conjunction with the first aspect, in some implementations, the housing of the second wheel-end controller among the additional three wheel-end controllers includes a second brake pedal sensor interface for connecting the brake pedal sensor. In response to the failure of both the first wheel-end controller and the central controller, the second wheel-end controller is also configured to control the brakes of the three additional wheel-end braking devices to brake the three wheels of the electric vehicle based on the brake pedal opening indicated by the brake pedal sensor.
[0033] It is understood that the wheel-end controller used to connect to the brake pedal sensor among the other three wheel-end controllers provided in this application embodiment is the second wheel-end controller. In other words, the second wheel-end controller refers to the wheel-end controller connected to the brake pedal sensor, and does not specifically refer to one of the other three wheel-end controllers, but can be any one of the other three wheel-end controllers.
[0034] It is understandable that when the second wheel-end controller detects a failure in the first wheel-end controller, it can control the corresponding actuator to output braking force and output braking control signals to all or part of the wheel-end controllers of the other two wheel-end braking devices. These braking control signals are used to indicate the braking force that the brake corresponding to the receiving wheel-end controller needs to output. In other words, by connecting the brake pedal sensor signal to the second wheel-end controller, the second wheel-end controller can control the brakes of the other three wheel-end braking devices to output braking force based on the brake pedal opening indicated by the brake pedal signal when both the central controller and the first wheel-end controller fail.
[0035] According to the present application, the electromechanical braking system may include two redundant wheel-end controllers to control the brakes in the other three wheel-end braking devices to output braking force when the central controller and the second wheel-end controller fail, thereby further improving the safety and reliability of the braking system.
[0036] In conjunction with the first aspect, in some implementations, the second brake pedal sensor interface is used to receive at least one brake pedal signal from the brake pedal sensor, and this at least one brake pedal signal is different from the brake pedal signal received by the first wheel-end controller. That is, the brake pedal sensor signal can be divided into at least three groups, the first wheel-end controller can receive at least two of these groups of brake pedal signals, and the second wheel-end controller is used to receive at least one additional group of brake pedal signals.
[0037] It is understandable that when the first wheel-end controller fails because it cannot receive the brake pedal signal provided by the brake pedal sensor and is unable to make a decision, the second wheel-end controller can receive at least one other brake pedal signal, thus enabling the second wheel-end controller to normally control the brake output of the brakes in the other three wheel-end braking devices.
[0038] According to the present application, the first wheel end controller and the second wheel end controller can obtain signals from the accelerator pedal sensor through different links to achieve signal redundancy, which can further improve the reliability and safety of the electromechanical braking system.
[0039] In conjunction with the first aspect, in some implementations, the first wheel-end controller is also configured to receive at least one brake pedal signal from the second wheel-end controller via the control interface, and control the brakes in the four wheel-end braking devices to brake the four wheels of the electric vehicle according to the brake pedal opening indicated by at least one of the brake pedal signal from the brake pedal sensor or the at least one brake pedal signal from the second wheel-end controller.
[0040] According to the embodiments of this application, the first wheel-end controller and the second wheel-end controller can interact with each other through a control interface to receive brake pedal signals. This allows the first wheel-end controller to determine the opening degree of the brake pedal by combining the brake pedal signals provided by the brake pedal sensor and the second wheel-end controller, thereby achieving brake control. This is beneficial to improving the reliability and accuracy of the brake control of the first wheel-end controller.
[0041] In conjunction with the first aspect, in some implementations, the housing surface of the first wheel-end controller further includes an inertial sensor interface for receiving acceleration signals and vehicle attitude signals from inertial sensors. The acceleration signals are used to indicate the acceleration of the electric vehicle, and the vehicle attitude signals are used to indicate at least one of the pitch rate, roll rate, or yaw rate of the electric vehicle.
[0042] It is understandable that the first wheel-end controller can dynamically adjust the braking force of the brakes on the four wheel-end devices based on acceleration signals and vehicle attitude signals to achieve functions such as traction control system and vehicle dynamic control. For example, when an electric vehicle is avoiding obstacles at high speed, the first wheel-end brake can monitor the vehicle's roll rate and lateral acceleration based on acceleration signals and vehicle attitude signals, thereby controlling the brakes on the two outer wheel-end braking devices of the electric vehicle to output braking force to achieve single-sided braking, thereby reducing the vehicle speed and generating a counter-torque to counteract the roll.
[0043] According to the present application, the signal from the inertial sensor is connected to the first wheel-end controller, which enables the first wheel-end controller to dynamically adjust the braking force output by the braking system based on the vehicle acceleration signal and the vehicle body attitude signal, thereby improving the vehicle's driving performance.
[0044] In conjunction with the first aspect, in some implementations, the housing surface of the first wheel-end controller further includes a parking switch interface and a parking control interface. The parking switch interface is used to connect to the electronic parking brake system switch of the electric vehicle, and the parking control interface is used to connect to the electronic parking brake system switch of the electric vehicle. The first wheel-end controller is also used to control the output of parking braking force of the electronic parking brake system of the electric vehicle through the parking control interface.
[0045] According to the present application, the electronic parking brake system switch is connected to the first wheel-end controller, which enables the first wheel-end controller to control parking and improves the integration of the wheel-end controller.
[0046] In conjunction with the first aspect, in some implementations, the housing surface of the first wheel-end controller further includes a wheel speed sensor interface for receiving a wheel speed signal from the wheel speed sensor, which indicates the rotational speed of the wheels of the electric vehicle.
[0047] It is understood that the housing surface of the first wheel-end controller includes a wheel speed sensor interface, so that the control circuit in the first wheel-end controller can connect to the wheel speed sensor through the wheel speed sensor interface to receive wheel speed signals from multiple wheel speed sensors, the wheel speed signals being used to indicate the rotational speed of each wheel of the electric vehicle.
[0048] According to the present application, the first wheel-end controller can adjust the braking output of the brakes in the four wheel-end braking devices according to the wheel speed indicated by the wheel speed signal, thereby maintaining the stability of the vehicle body during braking. For example, when the electric vehicle is traveling on a road surface with different coefficients of friction on the left and right sides, the first wheel-end controller can control the brakes in the wheel-end braking devices on the left and right sides to output different braking forces, thereby maintaining the stability of the electric vehicle body.
[0049] In conjunction with the first aspect, in some implementations, the housing surface of the first wheel-end controller further includes a height sensor interface and a suspension control interface. The height sensor interface is used to connect to the height sensor of the electric vehicle, and the suspension control interface is used to connect to the suspension system of the electric vehicle. The first wheel-end controller is also used to control the suspension system to adjust the suspension damping based on the vehicle height indicated by the height sensor.
[0050] It is understandable that during the braking process of an electric vehicle, the first wheel-end controller can simultaneously control the brakes of the four wheel-end braking devices to output braking force to the four wheels, and calculate based on the height signal from the height sensor, and control the electric vehicle's suspension system through the suspension control interface to adjust the suspension height or damping of the electric vehicle at the wheels, thereby improving the vehicle's stability during intense braking. In other words, the first wheel-end controller can jointly control the braking system and the suspension system, coordinating the adjustment of the braking force of the four wheel-end braking devices and the suspension height, which is beneficial to improving the driving performance of the electric vehicle.
[0051] According to an embodiment of this application, the first wheel-end controller can be connected to a height sensor, thereby controlling the suspension system of the electric vehicle based on the height signal indicated by the height sensor, thereby improving the driving performance of the electric vehicle through the coordinated operation of the braking system and the suspension system.
[0052] In conjunction with the first aspect, in some implementations, the housing surface of the first wheel-end controller further includes a smart driving signal input interface. This interface is used to receive smart driving signals from the smart driving controller of the electric vehicle. These smart driving signals are used to control the electric vehicle's drive system, braking system, and suspension system. The first wheel-end controller is used to control the brakes in the four wheel-end braking devices to brake the four wheels of the electric vehicle according to the instructions of the smart driving signals.
[0053] According to the embodiments of this application, the first wheel-end controller can control the braking system in response to the intelligent driving signal output by the intelligent driving controller, which is highly practical.
[0054] In a second aspect, an electric vehicle is provided, the electric vehicle including an electromechanical braking system for four wheels in any implementation of the first aspect, the electromechanical braking system being used to output braking force to the wheels to brake the four wheels. Attached Figure Description
[0055] Figure 1 is a schematic diagram of an electric vehicle provided in an embodiment of this application;
[0056] Figure 2 is a schematic diagram of the structure of a wheel-end braking device 210 provided in an embodiment of this application;
[0057] Figure 3 is a schematic diagram of the first wheel-end controller 211 provided in an embodiment of this application;
[0058] Figure 4 is a connection diagram of the electromechanical braking system 20 provided in an embodiment of this application;
[0059] Figure 5 is another connection diagram of the electromechanical braking system 20 provided in an embodiment of this application;
[0060] Figure 6 is another connection diagram of the electromechanical braking system 20 provided in the embodiments of this application. Detailed Implementation
[0061] The technical solutions in this application will now be described with reference to the accompanying drawings.
[0062] References to “some embodiments” and the like in this specification mean that one or more embodiments of this application include a particular feature, structure, or characteristic described in connection with that embodiment. Therefore, phrases such as “some embodiments” appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean “one or more, but not all, embodiments”, unless otherwise specifically emphasized. The terms “comprising,” “including,” “having,” and variations thereof mean “including, but not limited to,” unless otherwise specifically emphasized.
[0063] With the widespread adoption of automobiles, the requirements for vehicle safety are increasing. Vehicle braking systems have always played a crucial role in vehicle safety, and their importance has become increasingly apparent with the rapid development of automotive technology and the continuous increase in vehicle speeds. As braking performance demands rise, traditional hydraulic or air braking systems, with the addition of numerous electronic control systems such as anti-lock braking systems (ABS) and traction control systems (TCS), have become increasingly complex in structure and piping layout. This increases the risk of leaks in hydraulic (air) circuits and also raises the difficulty of assembly and maintenance. Therefore, electro-mechanical braking systems (EMBs), with their relatively simple structure and reliable integrated functions, are gaining popularity. However, current EMBs typically require at least one central controller to identify braking demand and distribute braking torque, resulting in higher system complexity and cost.
[0064] In view of this, embodiments of this application provide an electromechanical braking system and an electric vehicle, which enables the wheel-end control device to perform braking control based on the brake pedal opening by connecting the brake pedal sensor signal to one of the wheel-end braking devices, thereby simplifying the structure of the braking system while ensuring the braking performance of the electromechanical braking system.
[0065] Figure 1 is a schematic diagram of a vehicle provided in an embodiment of this application. As shown in Figure 1, the vehicle 10 includes a braking system 20 and four wheels. The braking system includes four wheel-end braking devices 210-240, which are respectively disposed at the four wheels of the vehicle. The vehicle 10 may also include a power battery (not shown in the figure) connected to the braking system 20, which supplies power to the four wheel-end braking devices in the braking system 20. The electric vehicle 10 also includes a brake pedal and a parking button, which allow the driver to control the vehicle's driving state. The travel of the brake pedal and the state of the parking button can control the wheel-end braking devices to perform braking and / or parking. During braking of the electric vehicle 10, the braking system 20 provides braking force to the four wheels.
[0066] The embodiments of this application are mainly applied to vehicles during braking and parking. The electric vehicle 10 includes, but is not limited to, pure electric vehicles (pure electric vehicle / battery electric vehicle, pure EV / battery EV), hybrid electric vehicles (HEV), range-extended electric vehicles (REEV), plug-in hybrid electric vehicles (PHEV), and new energy vehicles (NEV).
[0067] In some embodiments, the electric vehicle 10 further includes a drive system 30. The drive system 30 can be a single-motor drive architecture, a dual-motor drive architecture, a tri-motor drive architecture, or a quad-motor drive architecture. The drive system 30 can be a distributed quad-motor drive architecture, with the drive motors positioned beside the driving wheels and controlled by individual motor controllers. The drive system 30 can also be a centralized drive motor architecture, with drive motors for driving two front wheels or two rear wheels arranged together. There can be one or more motor controllers. A one-to-one correspondence can exist between a motor controller and a drive motor, or one motor controller can correspond to multiple drive motors.
[0068] The electric vehicle 10 also includes an accelerator pedal and a brake pedal. The accelerator pedal is used to indicate the torque output to the wheels of the electric vehicle 10. The brake pedal is used to indicate the braking force output to the wheels of the electric vehicle 10. During driving, when the electric vehicle 10 needs to be driven, the driver depresses the accelerator pedal, and the drive system 30 outputs torque according to the opening of the accelerator pedal, thereby driving the wheels of the electric vehicle 10. When the electric vehicle 10 needs to be braked, the driver depresses the brake pedal, and the braking system 20 outputs torque according to the opening of the brake pedal, thereby braking the wheels of the electric vehicle 10.
[0069] In some embodiments, the electric vehicle 10 further includes a suspension system 40 (not shown), which connects the body of the electric vehicle 10 to the wheels and provides support, cushioning, and stability during operation. The suspension system 40 includes shock absorbers. Each wheel is individually connected to the body of the electric vehicle 10 via a shock absorber. For a suspension system 40 with adjustable damping shock absorbers, the suspension system 40 can adjust the damping of each shock absorber based on a received target damping coefficient or target damping level. The suspension system 40 may include air suspension or fully active suspension.
[0070] Figure 2 is a schematic diagram of a wheel-end braking device 210 provided in an embodiment of this application. As shown in Figure 2, the braking device includes a wheel-end controller 211 and a brake 212. The brake 212 may include a brake motor and an actuator. The actuator includes a reducer, a rotary-to-linear structure, and friction pads, etc.
[0071] The wheel-end controller 211 includes a control circuit and an inverter circuit (not shown in the figure). The control circuit is used to control the switching transistors in the inverter circuit to turn on and off. The inverter circuit is used to electrically connect to the three-phase windings of the brake motor. The output shaft of the brake motor is connected to the input shaft of the gearbox. The inverter circuit is used to output drive current to the brake motor and control the brake motor to output torque to the actuator so that the actuator outputs braking force.
[0072] In some possible implementations, the actuator can include a reducer, an output shaft, and a helical propulsion structure (rotation-to-linear conversion mechanism). During braking, the motor controller controls the motor to rotate and outputs torque through the reducer's output shaft. The rotation-to-linear conversion mechanism converts the rotational motion of the output shaft into translational motion, thereby pushing the friction pads to squeeze the brake disc. When the brake disc is clamped, frictional force is generated between it and the vehicle's wheels, i.e., frictional braking force. This frictional braking force prevents the wheels from rotating or prevents the wheels from rotating, thus slowing down or even stopping a moving vehicle, maintaining a stable speed for a vehicle traveling downhill, or keeping a stopped vehicle stationary.
[0073] Figure 3 shows a schematic diagram of the first wheel-end controller 211 provided in an embodiment of this application. Figure 4 shows a connection schematic diagram of the electromechanical braking system 20 provided in an embodiment of this application.
[0074] Referring to Figures 3 and 4, in some embodiments, the housing surface of the first wheel-end controller 211 among the four wheel-end braking devices includes a brake pedal sensor interface and a control interface. The brake pedal sensor interface is used to connect to the brake pedal sensor of the electric vehicle 10, and the control interface is used to connect to the wheel-end controllers of the other three wheel-end braking devices. The first wheel-end controller 211 is used to control the brakes of the four wheel-end braking devices to brake the four wheels of the electric vehicle 10 according to the brake pedal opening indicated by the brake pedal sensor.
[0075] It is understood that the wheel-end controller used to connect to the brake pedal sensor among the four wheel-end controllers provided in this application embodiment is the first wheel-end controller 211. In other words, the first wheel-end controller refers to the wheel-end controller connected to the brake pedal sensor, and does not specifically refer to one of the four wheel-end controllers, but can be any one of the four wheel-end controllers.
[0076] The brake pedal sensor can be of different types, such as a brake pedal displacement sensor or a brake pedal pressure sensor, and this application embodiment is not limited to any particular type. The brake pedal displacement sensor monitors the movement angle of the brake pedal. The first wheel-end controller 211 can calculate the brake pedal travel or opening degree based on the brake pedal travel angle from the brake pedal sensor, thereby obtaining the braking force requirement of the electric vehicle 10. The brake pedal pressure sensor monitors the pressure acting on the brake pedal. The first wheel-end controller 211 can calculate the braking travel or opening degree based on the pressure acting on the brake pedal, thereby obtaining the braking force requirement of the electric vehicle 10.
[0077] The first wheel-end controller 211 connects to the brake pedal sensor via a brake pedal sensor interface, allowing the control circuit within the controller to receive brake pedal signals from the sensor through the interface and internal wiring. This enables the controller to identify braking force requirements based on the brake pedal signals. The brake pedal opening indicates the driver's required braking force; a larger opening indicates a greater braking demand, requiring a larger braking force from the braking system 20. During normal vehicle operation, the first wheel-end controller 211 controls the wheel-end braking device to output the braking force indicated by the brake pedal opening. A larger opening requires a larger braking force, and a smaller opening requires a smaller braking force. In other words, the braking force output by the wheel-end braking device changes with the brake pedal opening.
[0078] Furthermore, the first wheel end controller 211 is connected to the other three wheel end controllers through the control interface on the surface of the housing, so that the control circuit in the first wheel end controller 211 can send control signals to some or all of the other three wheel end controllers through the control interface, thereby controlling the corresponding brake to output braking force.
[0079] In other words, after determining the required braking force of the four brakes based on the brake pedal opening, the first wheel-end controller 211 can control the braking torque output by the brake motor to the actuator without needing to distribute the braking force through the central controller. Simultaneously, the first wheel-end controller 211 can also output braking control signals to some or all of the other three wheel-end controllers via a control interface. These braking control signals indicate the required braking force for the brake corresponding to the receiving wheel-end controller.
[0080] It is understood that the first-round end controller 211 can connect to the sensors and actuators of the electric vehicle 10 and interact with signals via a local area network (CAN) bus, Ethernet, local interconnect network (LIN) bus, high-speed fault-tolerant network protocol (FlexRay) or other types of connection methods.
[0081] According to the present application, the signal of the brake pedal sensor is connected to the wheel end controller of a wheel end braking device. The wheel end controller identifies the braking demand and distributes the braking force based on the brake pedal sensor signal, which simplifies the structure of the braking system while ensuring the braking performance of the electromechanical braking system.
[0082] Referring again to Figure 4, in some embodiments, the control interface is used to connect to three additional wheel-end controllers via at least two internal local area network (LAN) buses. That is, the wheel-end controllers of the four wheel-end braking devices can be interconnected via at least two LAN buses.
[0083] It is understood that the first wheel-end controller 211 is connected to each wheel-end braking device via at least two sets of internal CAN buses, and this can be increased to three or four internal controller area network (CAN) buses depending on the actual communication load rate. In other implementations, other high-speed communication methods can also be used for connection.
[0084] It is understandable that when one CAN bus fails, another CAN bus can be used to maintain the connection between the first wheel end controller 211 and the other three wheel end controllers, thus maintaining the control of the braking system 20 by the first wheel end controller 211.
[0085] Figure 5 shows another connection diagram of the electromechanical braking system provided in the embodiment of this application.
[0086] In some embodiments, the electromechanical braking system 20 further includes a central controller 250, which receives a brake pedal signal from another brake pedal sensor. The control interface of the first wheel-end controller 211 is also connected to the central controller 250. In response to the central controller 250 being active, the first wheel-end controller 211 controls the corresponding brake 212 to output braking force according to the braking control signal from the central controller. In response to the central controller 250 being inactive, the first wheel-end controller 211 controls the brakes in the four wheel-end braking devices to brake the four wheels of the electric vehicle 10 according to the brake pedal opening indicated by the brake pedal sensor. Correspondingly, when the central controller 250 is active, the first wheel-end controller 211 can control the brake 212 to output braking force corresponding to the brake pedal opening according to the braking control signal received from the central controller 250.
[0087] It is understood that the central controller 250 can serve as the main controller in the electromechanical braking system 20. When the central controller 250 is active, the first wheel-end controller 211 can act as an actuator, controlling the corresponding brake 212 to output braking force according to the braking control signal from the central controller.
[0088] It is understood that when the central controller 250 fails, the first wheel-end controller 211, acting as a computing center, controls the brakes in the four wheel-end braking devices to output braking force to the wheels of the electric vehicle 10 based on the brake pedal opening indicated by the brake pedal sensor. This application does not limit the specific method by which the first wheel-end controller 211 determines that the central controller 250 has failed. In some embodiments, the signals interacting between the central controller 250 and the four wheel-end controllers may include a central controller valid bit signal, which indicates whether the central controller 250 is valid or failed. Furthermore, the central controller 250 sends the central controller valid bit signal to the four wheel-end controllers, allowing the four wheel-end controllers to obtain the current valid state of the central controller 250. In some embodiments, when the central controller fails, the central controller 250 loses the ability to communicate with the four wheel-end controllers. That is, when the four wheel-end controllers cannot receive signals from the central controller 250, they will determine that the central controller 250 has failed.
[0089] In this embodiment, functions such as braking force demand identification and braking force distribution can be redundantly implemented within the central controller 250 and the first wheel-end controller 211. That is, the control function of the first wheel-end controller 211 at least includes basic braking. Depending on actual chip resources and cost, the control function of the first wheel-end controller 211 may also include an anti-lock braking system (ABS), a traction control system (TCS), vehicle dynamic control (VDC), or some of these functions.
[0090] According to the embodiments of this application, the first wheel-end controller 211 can serve as a redundant controller in the electromechanical braking system, so as to continue to control the brakes in the four wheel-end braking devices to output braking force when the central controller 250 fails, thereby avoiding the failure of the central controller leading to the failure of the entire electromechanical braking system 20, and improving the safety and reliability of the braking system.
[0091] Referring again to Figure 5, in some embodiments, the brake pedal sensor interface is used to receive at least two brake pedal signals from the brake pedal sensor, and the central controller 250 is used to receive at least two brake pedal signals from another brake pedal sensor.
[0092] It is understood that the brake pedal of the electric vehicle 10 can be equipped with multiple sensors, which are divided into two groups. The first wheel-end controller 211 receives the brake pedal signals output by one group of brake pedal sensors, and the central controller 250 receives the brake pedal signals output by the other group of brake pedal sensors. For example, brake pedal sensors 1 / 2 form one group, and 3 / 4 form another. Brake pedal sensor signal 1 is (5V power supply 1, sent signal 1, GND1); brake pedal sensor signal 2 is (5V power supply 2, sent signal 2, GND2); brake pedal sensor signal 3 is (5V power supply 3, sent signal 3, GND3); and brake pedal sensor signal 4 is (5V power supply 4, sent signal 4, GND4). Brake pedal sensor signals 1 / 2 are connected to the first wheel-end controller 211; brake pedal sensor signals 3 / 4 are connected to the central controller 250.
[0093] According to an embodiment of this application, the electromechanical braking system 20 provided in this application includes two brake pedal sensors that serve as backups for each other. The two brake pedal sensors are respectively connected to the central controller 250 and the first wheel-end controller 211. On the one hand, the two brake pedal sensors can more accurately detect the movement state of the brake pedal; on the other hand, if one brake pedal sensor fails, the other brake pedal sensor can still independently detect the movement state of the brake pedal, thereby improving the operational reliability of the electromechanical braking system 20.
[0094] In some embodiments, the first wheel-end controller 211 is further configured to output at least two brake pedal signals from the brake pedal sensor to the central controller 250 via a control interface.
[0095] It is understood that the first wheel end controller 211 may directly output the received signal to the central controller 250 when it receives at least two brake pedal signals from the brake pedal sensor, or it may output the received signal to the first wheel end controller 211 in response to a signal from the central controller 250 indicating brake sensor failure. This application embodiment does not limit this.
[0096] For example, the signals exchanged between the first wheel-end controller 211 and the central controller 250 may also include a valid bit signal for another brake pedal sensor, which indicates whether the other brake pedal sensor is valid or invalid. Specifically, the central controller 250 can determine whether the other brake pedal sensor is valid based on the brake pedal signal sent from it and output the valid bit signal. When the state indicated by the valid bit signal generated by the central controller 250 is valid, the brake pedal sensor is valid. When the state indicated by the valid bit signal generated by the central controller 250 is invalid, the brake pedal sensor is invalid. When the brake pedal sensor cannot monitor the movement state of the brake pedal, or the central controller 250 cannot receive the brake pedal signal, the state indicated by the valid bit signal issued by the central controller 250 is invalid. Further, the central controller 250 can send the valid bit signal of the other brake pedal sensor to the four wheel-end controllers, so that the four wheel-end controllers can determine the current state of the other brake pedal sensor based on the signal.
[0097] In this embodiment, since the central controller 250 can receive the brake pedal signal from the brake pedal sensor through the first wheel-end controller 211, the central controller 250 can still control the four wheel-end braking devices to output the braking force corresponding to the brake pedal opening based on the brake pedal opening indicated by the brake pedal signal.
[0098] In some embodiments, the housing of the first wheel-end controller 211 further includes a first communication interface. The first wheel-end controller 211 is also used to receive an accelerator pedal signal from the vehicle controller via the first communication interface. The accelerator pedal signal is used to indicate the opening degree of the accelerator pedal of the electric vehicle 10. In response to the failure of both the brake pedal sensor and another brake pedal sensor and a decrease in the accelerator pedal opening indicated by the accelerator pedal signal, the first wheel-end controller 211 controls the brakes of the four wheel-end braking devices to output braking force to the four wheels of the electric vehicle, wherein the braking force increases as the accelerator pedal opening decreases.
[0099] The housing of the first wheel-end controller 211 includes a first communication interface, allowing the control circuit of the first wheel-end controller 211 to receive accelerator pedal signals from the vehicle controller. If the brake pedal sensor and another brake pedal sensor both fail, and the accelerator pedal opening indicated by the accelerator pedal sensor decreases, this can be interpreted as the driver releasing the accelerator pedal. At this time, the first wheel-end controller 211 can control the brakes in the four wheel-end braking devices to output braking force, thereby assisting the electric vehicle 10 to gradually decelerate until it comes to a stop. In other words, even if the brake pedal sensor of the electric vehicle 10 fails, the driver can control the four wheel-end braking devices to brake the four wheels of the electric vehicle 10 by manipulating the accelerator pedal.
[0100] It is understandable that after both the brake pedal sensor and the other brake pedal sensor fail, the first wheel end controller 211 can still report alarm information to the vehicle controller. The vehicle controller can alert the driver of the brake pedal failure through the in-vehicle display screen, audio system, ambient light flashing, etc., and display a preset animation on the in-vehicle display screen to guide the driver to control the vehicle braking by slowly releasing the accelerator pedal, thus ensuring driving safety.
[0101] Furthermore, in some embodiments, during the accelerator pedal opening decrease, if the accelerator pedal opening is greater than or equal to a preset opening, the first wheel-end controller 211 will not control the four wheel-end braking devices to output braking force, and the electric vehicle 10 can be in a coasting state. When the accelerator pedal opening decreases to less than the preset opening, the first wheel-end controller 211 controls the four wheel-end braking devices to output braking force. For example, the preset opening is 30%, and the process of the accelerator pedal opening decreasing from greater than 30% to 0% is divided into two stages. When the accelerator pedal opening is greater than or equal to 30%, the first wheel-end controller 211 will not control the four wheel-end braking devices to output braking force. When the accelerator pedal signal is less than 30%, the first wheel-end controller 211 controls the four wheel-end braking devices to output braking force, and the smaller the accelerator pedal signal, the greater the braking force output by the four wheel-end braking devices.
[0102] According to the embodiments of this application, in the scenario where all brake pedal sensors configured in the electric vehicle 10 fail, the first wheel-end controller 211 can still control the output braking force of the four wheel-end devices based on the degree of reduction in the accelerator pedal opening, thereby avoiding the risk of brake failure caused by brake pedal sensor failure and improving the safety and reliability of the electric vehicle 10.
[0103] In some embodiments, the first wheel-end controller 211 is further configured to receive at least one accelerator pedal signal from the accelerator pedal sensor via a first communication interface.
[0104] In other words, the control circuit of the first wheel-end controller 211 can also receive at least one accelerator pedal signal from the accelerator pedal sensor through the first communication interface. Thus, even if the brake pedal sensor and another brake pedal sensor fail, and the vehicle controller malfunctions or its connection to the vehicle controller fails, the first wheel-end controller 211 can still control the four brakes to output braking force to the four wheels based on the accelerator pedal opening using the accelerator pedal signal obtained from the accelerator pedal sensor.
[0105] It is understood that the signals output by the sensors in this application, such as accelerator pedal signals and brake pedal signals, are single-edge nibble transmission (SENT) signals, or analog voltage signals, or analog current signals, etc.
[0106] According to the solution of this application, the first wheel end controller 211 can acquire multiple signals from the accelerator pedal sensor to achieve signal redundancy, which can further improve the reliability and safety of the electromechanical braking system.
[0107] In some embodiments, in response to the failure of the accelerator pedal signal, the first wheel-end controller 211 controls the brakes of the four wheel-end braking devices to output a preset braking force to the brakes of the four wheels of the electric vehicle 10.
[0108] It is understandable that during the operation of electric vehicle 10, a failure of the accelerator pedal signal would cause the drive system of electric vehicle 10 to be unable to output torque based on the accurate accelerator pedal opening, resulting in uncontrolled power output of electric vehicle 10. In this situation, to prevent the driver from being unable to perform correct operations due to interference with driving confidence, the first wheel-end controller 211 will actively control the brakes of the four wheel-end braking devices to output a preset braking force, so that electric vehicle 10 gradually decelerates until it comes to a stop, thereby ensuring the driving safety of electric vehicle 10. Here, "active control" means that the first wheel-end controller 211 can control the four wheel-end braking devices to output braking force without relying on changes in brake pedal opening indicated by the brake pedal sensor or the brake control signal from the central controller 250, but can control the four wheel-end braking devices to output braking force in response to the failure of the accelerator pedal sensor.
[0109] Furthermore, when the brake pedal sensor is active, the first wheel-end controller 211 can also adjust the braking force output by the brakes in the four wheel-end braking devices in response to the change in brake pedal opening indicated by the brake pedal sensor during the output of the preset braking force.
[0110] It is understood that the specific value of the preset braking force is not limited in the embodiments of this application. Furthermore, the first wheel-end controller 211 can also dynamically adjust the braking force output by the four wheel-end braking devices in combination with the vehicle speed of the electric vehicle 10 and the wheel speed of the four wheels.
[0111] According to an embodiment of this application, the first wheel-end controller 211 can actively control the four wheel-end braking devices to output braking force when the accelerator pedal sensor fails, thereby actively reducing the vehicle speed and ensuring the driving safety of the electric vehicle.
[0112] Figure 6 shows another connection diagram of the electromechanical braking system provided in the embodiments of this application.
[0113] In some embodiments, the housing of the second wheel-end controller 221, one of the other three wheel-end controllers, includes a second brake pedal sensor interface for connecting a brake pedal sensor. In response to the failure of both the first wheel-end controller 211 and the central controller 250, the second wheel-end controller 221 is also configured to control the brakes of the other three wheel-end braking devices to brake the three wheels of the electric vehicle 10 based on the brake pedal opening indicated by the brake pedal sensor.
[0114] It is understood that the wheel-end controller used to connect to the brake pedal sensor among the other three wheel-end controllers provided in this application embodiment is the second wheel-end controller 221. In other words, the second wheel-end controller 221 refers to the wheel-end controller connected to the brake pedal sensor, and does not specifically refer to one of the other three wheel-end controllers, but can be any one of the other three wheel-end controllers. For example, the first wheel-end controller 211 can be a controller in a wheel-end braking device for braking the left front wheel of a vehicle, and the second wheel-end controller 221 can be a controller in a wheel-end braking device for braking the right front wheel of a vehicle. As another example, the first wheel-end controller 211 can be a controller in a wheel-end braking device for braking the left front wheel of a vehicle, and the second wheel-end controller 221 can be a controller in a wheel-end braking device for braking the right rear wheel of a vehicle.
[0115] It is understood that the signals exchanged between the first wheel-end controller 211 and the second wheel-end controller 221 may include a valid bit signal of the first wheel-end controller 211, which indicates whether the first wheel-end controller 211 is valid or invalid. Specifically, the first wheel-end controller 211 can detect its own valid state and send the valid bit signal to the second wheel-end controller 221. Correspondingly, when the valid bit signal received by the second wheel-end controller 221 indicates that the first wheel-end controller 211 has failed, the second wheel-end controller 221 can control the corresponding actuator to output braking force and output braking control signals to all or part of the wheel-end controllers of the other two wheel-end braking devices. These braking control signals are used to indicate the braking force that the brake corresponding to the wheel-end controller receiving the signal needs to output. In other words, by connecting the signal from the brake pedal sensor to the second wheel-end controller 221, the second wheel-end controller 221 can control the brakes of the other three wheel-end braking devices to output braking force according to the brake pedal opening indicated by the brake pedal signal when both the central controller 250 and the first wheel-end controller 211 have failed.
[0116] According to an embodiment of this application, the electromechanical braking system 20 may include two redundant wheel-end controllers to control the brakes in the other three wheel-end braking devices to output braking force when the central controller 250 and the second wheel-end controller 221 fail, thereby further improving the safety and reliability of the braking system.
[0117] In some embodiments, the second brake pedal sensor interface is used to receive at least one brake pedal signal from the brake pedal sensor, and at least one brake pedal signal is different from the brake pedal signal received by the first wheel-end controller. That is, the brake pedal sensor signal can be divided into at least three groups, the first wheel-end controller 211 can receive at least two of these groups of brake pedal signals, and the second wheel-end controller 221 is used to receive at least one other group of brake pedal signals.
[0118] It is understandable that when the first wheel-end controller 211 fails because it cannot receive the brake pedal signal provided by the brake pedal sensor and is unable to make a decision, the second wheel-end controller 221 can receive at least one other brake pedal signal, so that the second wheel-end controller 221 can normally control the brake output of the brakes in the other three wheel-end braking devices.
[0119] According to the embodiments of this application, the first wheel end controller 211 and the second wheel end controller 221 can obtain signals from the accelerator pedal sensor through different links to achieve signal redundancy, which can further improve the reliability and safety of the electromechanical braking system.
[0120] In some embodiments, the first wheel-end controller 211 is further configured to receive at least one brake pedal signal from the second wheel-end controller 221 via a control interface, and control the brake output of the four wheel-end braking devices to brake the four wheels of the electric vehicle 10 according to the brake pedal opening indicated by at least one of the brake pedal signal from the brake pedal sensor or the at least one brake pedal signal from the second wheel-end controller 221.
[0121] It is understood that the first wheel-end controller 211 and the second wheel-end controller 221 can exchange the brake pedal signals they receive. Therefore, when the communication between the first wheel-end controller 211 and the brake pedal sensor is normal, the first wheel-end controller 211 can receive the brake pedal signal directly transmitted by the brake pedal sensor, as well as at least one brake pedal signal forwarded by the second wheel-end controller 221, and determine the brake pedal opening degree through the two signals. At this time, the two brake pedal signals can serve as backups for each other, thereby improving the reliability and accuracy of brake control. Furthermore, when the communication between the first wheel-end controller 211 and the brake pedal sensor fails, the first wheel-end controller 211 can still control the brake output of the four wheel-end braking devices based on the brake pedal signal forwarded by the second wheel-end controller 221, corresponding to the brake pedal opening degree.
[0122] According to the embodiments of this application, the first wheel end controller 211 and the second wheel end controller 221 can interact with each other through a control interface to receive brake pedal signals. This allows the first wheel end controller 211 to determine the opening degree of the brake pedal by combining the brake pedal signals provided by the brake pedal sensor and the second wheel end controller 221, thereby achieving brake control. This is beneficial to improving the reliability and accuracy of the brake control of the first wheel end controller 221.
[0123] In some embodiments, the housing surface of the first wheel-end controller 211 further includes an inertial sensor interface. This interface receives acceleration signals and vehicle attitude signals from inertial sensors. The acceleration signals indicate the acceleration of the electric vehicle 10, and the vehicle attitude signals indicate at least one of the pitch, roll, or yaw angular velocities of the electric vehicle 10. The inertial sensor, also known as an inertial measurement unit (IMU), mainly includes inertial elements such as accelerometers (e.g., triaxial accelerometers), gyroscopes, and tilt sensors. The accelerometers detect the vehicle's acceleration signals relative to the inertial coordinate system, i.e., lateral acceleration, longitudinal acceleration, and vertical acceleration. The gyroscopes detect the vehicle's angular velocity signals relative to the inertial coordinate system. Processing the detected acceleration and angular velocity signals allows for the calculation of information such as the vehicle's position, velocity, and attitude.
[0124] In this embodiment, the first wheel-end controller 211 includes an inertial sensor interface, allowing its control circuit to connect to the inertial sensors of the electric vehicle 10, thereby acquiring the acceleration signal and vehicle attitude signal of the electric vehicle 10. The first wheel-end controller 211 can dynamically adjust the braking force of the brakes on the four wheel-end devices based on the acceleration signal and vehicle attitude signal to achieve functions such as traction control system and vehicle dynamic control. For example, when the electric vehicle 10 is avoiding obstacles at high speed, the first wheel-end controller 211 can monitor the vehicle's roll rate and lateral acceleration based on the acceleration signal and vehicle attitude signal, thereby controlling the brakes on the two outer wheel-end braking devices of the electric vehicle 10 to output braking force to achieve unilateral braking, thereby reducing the vehicle speed and generating a counter-torque to counteract the roll.
[0125] In some embodiments, the housing surface of the first wheel-end controller 211 further includes a parking switch interface for connecting to the electronic parking brake system switch of the electric vehicle 10. The electronic parking brake system switch controls the electronic parking system of the electric vehicle 10, allowing the driver to apply the parking brake. The housing surface of the first wheel-end controller 211 also includes a parking control interface for connecting to the electronic parking brake system switch of the electric vehicle 10. The first wheel-end controller 211 is also used to control the output of parking braking force by the electronic parking brake system of the electric vehicle through the parking control interface.
[0126] The electronic parking brake system switch controls the electronic parking system of the electric vehicle 10, allowing the driver to apply the parking brake. When the electronic parking brake system switch indicates that the electric vehicle 10 needs to be parked, the first wheel-end controller 211 controls the electronic parking brake system to output parking braking force.
[0127] In some embodiments, the housing surface of the first wheel-end controller 211 further includes a wheel speed sensor interface for receiving wheel speed signals from a wheel speed sensor, which in turn indicates the rotational speed of the wheels of the electric vehicle.
[0128] The housing surface of the first wheel-end controller 211 includes a wheel speed sensor interface, allowing the control circuit within the first wheel-end controller 211 to connect to wheel speed sensors via the wheel speed sensor interface. The wheel speed sensor receives wheel speed signals from multiple wheel speed sensors, which indicate the rotational speed of each wheel of the electric vehicle 10. This allows the control circuit in the first wheel-end controller 211 to adjust the braking output of the brakes in the four wheel-end braking devices based on the wheel rotational speed indicated by the wheel speed signals, thereby maintaining the stability of the vehicle body during braking. For example, when the electric vehicle 10 is traveling on a road surface with different coefficients of friction on the left and right sides, the first wheel-end controller 211 can control the brakes in the wheel-end braking devices on the left and right sides to output different braking forces, thereby maintaining the stability of the electric vehicle 10.
[0129] In some embodiments, the housing surface of the first wheel-end controller 211 further includes a height sensor interface and a suspension control interface. The height sensor interface is used to connect to the height sensor of the electric vehicle 10, and the suspension control interface is used to connect to the suspension system 40 of the electric vehicle 10. The first wheel-end controller 211 is also used to control the suspension system 40 to adjust the suspension damping according to the vehicle height indicated by the height sensor. In these embodiments, the first wheel-end controller 211 can also be connected to the height sensor of the electric vehicle 10 through the height sensor interface on the housing surface, so that the control circuit in the first wheel-end controller 211 can transmit the height signal from the height sensor through the height sensor interface and internal wiring, which is used to indicate the vehicle height.
[0130] It is understandable that the first wheel end controller 211 can also combine the height signal provided by the height sensor and the vertical acceleration signal provided by the inertial sensor (especially the triaxial accelerometer) to control the suspension system 40 of the electric vehicle 10 to adjust the suspension damping.
[0131] The suspension system 40 connects the body of the electric vehicle 10 to its wheels, providing support, cushioning, and stability during the operation of the electric vehicle 10. The suspension system 40 includes shock absorbers. Each wheel is individually connected to the body of the electric vehicle 10 via a shock absorber. In this embodiment, for the suspension system 40 with adjustable damping shock absorbers, a first wheel-end controller 211 sends a target damping coefficient or target damping level to the suspension system 40 to adjust the damping of each shock absorber. The suspension system 40 includes an air suspension or a fully active suspension. The first wheel-end controller 211 sends a target wheel suspension height to the suspension system 40 to adjust the suspension height at the wheels of the electric vehicle 10.
[0132] In some embodiments, the first wheel-end controller 211 is used to connect to an independent suspension controller of the electric vehicle 10 via a suspension control interface. The suspension controller is used to drive the suspension actuators to adjust the suspension damping. The control circuit in the first wheel-end controller 211 is used to send suspension signals to the suspension controller, which instruct the suspension controller to drive the suspension actuators to adjust the suspension damping. For suspension actuators in the form of CDC, air springs, or active suspension oil pump actuators, the first wheel-end controller 211 controls an independent suspension drive plate via suspension signals. The suspension controller sends PWM solenoid valve drives to the CDC, or to the air spring, or sends control commands to the oil pump actuator via communication commands, thereby adjusting the suspension damping.
[0133] In some embodiments, the first wheel-end controller 211 is used to connect to the suspension actuator via a suspension control interface, so that the control circuit of the first wheel-end controller 211 can directly control the suspension actuator to adjust the suspension damping through the suspension control interface. In these embodiments, the first wheel-end controller 211 includes the suspension drive circuit, which can directly send PWM solenoid valve drive to the CDC, or send PWM solenoid valve drive to the air spring, or send control commands to the oil pump actuator via communication commands, thereby adjusting the suspension damping.
[0134] In some embodiments, the housing surface of each wheel-end controller in the electromechanical braking system 20 can include a suspension control interface. The first wheel-end controller 211, acting as the computing center, calculates the suspension height for each wheel by combining height and vertical acceleration signals. It can then send suspension control signals to the other three wheel-end controllers via the control interface. Thus, each wheel-end controller can send suspension control signals to its own wheel-side suspension drive plate or hydraulic pump actuator via its own suspension control interface, thereby adjusting the suspension damping. Alternatively, in embodiments where the suspension drive circuit is integrated into each wheel-end controller, each wheel-end controller can also directly control the suspension actuator to adjust the suspension damping based on the received suspension control signal. In this way, each wheel-end controller can act as a relay for suspension control signals or participate in suspension control as part of an actuator, resulting in a higher level of integration and greater practicality for the electromechanical braking system.
[0135] Furthermore, during the braking process of the electric vehicle 10, the first wheel-end controller 211 can, while controlling the brakes of the four wheel-end braking devices to output braking force to the four wheels, simultaneously control the suspension system of the electric vehicle 10 through the suspension control interface to adjust the suspension height or damping of the electric vehicle 10 wheels, thereby improving the vehicle stability of the electric vehicle 10 during intense braking. For example, when the brake pedal opening is less than a preset threshold, i.e., the driver's braking demand is low, the first wheel-end controller 211 can control the brakes of the four wheel-end braking devices to output braking force corresponding to the brake pedal opening, and control the braking system to reduce suspension damping, thereby reducing the driver's and passengers' perception of braking and improving ride comfort. Conversely, when the brake pedal opening is greater than a preset threshold, i.e., the driver's braking demand is high, the first wheel-end controller 211 can control the brakes of the four wheel-end braking devices to output braking force corresponding to the brake pedal opening, and control the braking system to increase suspension damping, thereby reducing the vehicle's "brake dive" phenomenon. In other words, the first wheel-end controller 211 can jointly control the braking system 20 and the suspension system 40, and coordinately adjust the braking force of the four wheel-end braking devices and the height of the suspension, which is beneficial to improving the driving performance of the electric vehicle 10.
[0136] According to an embodiment of this application, the first wheel-end controller 211 can be connected to a height sensor, thereby controlling the suspension system of the electric vehicle 10 based on the height signal indicated by the height sensor, thereby improving the driving performance of the electric vehicle 10 through the coordinated operation of the braking system and the suspension system.
[0137] In some embodiments, the housing surface of the first wheel-end controller 211 further includes a smart driving signal input interface, which is used to receive smart driving signals from the smart driving controller of the electric vehicle. These smart driving signals are used to control the electric vehicle's drive system, braking system, and suspension system. The first wheel-end controller 211 is used to control the brakes in the four wheel-end braking devices to brake the four wheels of the electric vehicle according to the instructions of the smart driving signals.
[0138] In one embodiment, the intelligent driving controller of the electric vehicle 10 can be a domain controller for realizing functions such as perception, positioning, path planning, and decision control. When the electric vehicle 10 is in intelligent driving mode, the intelligent driving controller performs intelligent active driving or assists the user in driving. The intelligent driving controller receives perception data signals sent by the electric vehicle 10's sensing components, such as radar and cameras. The intelligent driving controller fuses the information perceived by various sensors and obtains the driving status and lane information of the electric vehicle 10 based on the perception data signals. By analyzing signals such as distance, speed, and acceleration, it obtains target acceleration and target speed, etc. Based on the fused information, it makes driving decisions and plans, and sends intelligent driving signals to the controllers of various systems, thereby controlling the drive system 30, braking system 20, and suspension system 40 to achieve intelligent driving.
[0139] The electric vehicle 10 can detect its surrounding environment and operational status information through a perception system. The perception system includes sensors such as cameras, lidar, and millimeter-wave radar to perceive the surrounding environment and collect and process environmental and in-vehicle information, primarily involving technologies such as road boundary monitoring, vehicle detection, and pedestrian detection. The perception system also includes sensors such as vehicle speed sensors, acceleration sensors, and inertial measurement units to detect vehicle status and driving information. Perception data signals include relative distance, relative speed, relative acceleration, and lane information. Perception signals may also include information such as the electric vehicle 10's speed, acceleration, roll rate, and yaw rate. Based on the acquired perception data, the electric vehicle 10 detects information about itself and obstacles and plans a driving path. The electric vehicle 10 uses sensors such as cameras and radar to detect the distance between itself and obstacles in real time for obstacle avoidance maneuvers.
[0140] According to the embodiments of this application, the first wheel end controller 211 can control the braking system 20 in response to the instruction of the intelligent driving controller to output intelligent driving signal, which is highly practical.
[0141] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.
Claims
1. An electromechanical braking system, characterized in that, The electromechanical braking system includes four wheel-end braking devices, each wheel-end braking device including a wheel-end controller and a brake, and each wheel-end controller controlling the brake to output braking force, wherein: The housing surface of the first wheel-end controller in the four wheel-end braking devices includes a brake pedal sensor interface and a control interface. The brake pedal sensor interface is used to connect to the brake pedal sensor of the electric vehicle, and the control interface is used to connect to the other three wheel-end controllers. The first wheel-end controller is used to control the brakes in the four wheel-end braking devices to brake the four wheels of the electric vehicle according to the brake pedal opening indicated by the brake pedal sensor.
2. The electromechanical braking system according to claim 1, characterized in that, The electromechanical braking system further includes a central controller for receiving brake pedal signals from another brake pedal sensor. The control interface is also used to connect to the central controller. The first wheel-end controller is further used for: In response to the central controller being active, the corresponding brake is controlled to output braking force according to the indication of the braking control signal from the central controller; In response to a failure of the central controller, the brakes in the four wheel-end braking devices are controlled to brake the four wheels of the electric vehicle based on the brake pedal opening indicated by the brake pedal sensor.
3. The electromechanical braking system according to claim 2, characterized in that, The brake pedal sensor interface is used to receive at least two brake pedal signals from the brake pedal sensor, and the central controller is used to receive at least two brake pedal signals from the other brake pedal sensor.
4. The electromechanical braking system according to claim 2 or 3, characterized in that, The first wheel-end controller is also used to output at least two brake pedal signals from the brake pedal sensor to the central controller via the control interface.
5. The electromechanical braking system according to any one of claims 2 to 4, characterized in that, The housing of the first wheel-end controller also includes a first communication interface. The first wheel-end controller is further configured to receive an accelerator pedal signal from the vehicle controller via the first communication interface. The accelerator pedal signal is used to indicate the opening degree of the accelerator pedal of the electric vehicle. The first wheel-end controller is further configured to: In response to the failure of both the brake pedal sensor and the other brake pedal sensor and a decrease in the accelerator pedal opening indicated by the accelerator pedal signal, the brakes of the four wheel-end braking devices are controlled to output braking force to the four wheels of the electric vehicle, wherein the braking force increases as the accelerator pedal opening decreases.
6. The electromechanical braking system according to claim 5, characterized in that, The first wheel-end controller is also configured to receive at least one accelerator pedal signal from the accelerator pedal sensor of the electric vehicle via the first communication interface.
7. The electromechanical braking system according to claim 5 or 6, characterized in that, The first wheel-end controller is also used for: In response to the failure of the accelerator pedal signal, the brakes of the four wheel-end braking devices are controlled to output a preset braking force to the brakes of the four wheels of the electric vehicle.
8. The electromechanical braking system according to claim 2, characterized in that, The housing of the second wheel-end controller in the other three wheel-end braking devices includes a second brake pedal sensor interface for connecting the brake pedal sensor. The second wheel-end controller is also used for: In response to the failure of both the first wheel-end controller and the central controller, the brakes in the other three wheel-end braking devices are controlled to brake the three wheels of the electric vehicle according to the brake pedal opening indicated by the brake pedal sensor.
9. The electromechanical braking system according to claim 8, characterized in that, The second brake pedal sensor interface is used to receive at least one brake pedal signal from the brake pedal sensor, and the at least one brake pedal signal is different from the brake pedal signal received by the first wheel-end controller.
10. The electromechanical braking system according to claim 9, characterized in that, The first wheel-end controller is also used for: The system receives at least one brake pedal signal from the second wheel-end controller via the control interface, and controls the brakes in the four wheel-end braking devices to brake the four wheels of the electric vehicle according to the brake pedal opening indicated by at least one of the brake pedal signals from the brake pedal sensor or the at least one brake pedal signal from the second wheel-end controller.
11. The electromechanical braking system according to any one of claims 1 to 10, characterized in that, The housing surface of the first wheel-end controller also includes an inertial sensor interface, which is used to receive acceleration signals and vehicle attitude signals from the inertial sensor. The acceleration signals are used to indicate the acceleration of the electric vehicle, and the vehicle attitude signals are used to indicate at least one of the pitch rate, roll rate, or yaw rate of the electric vehicle.
12. The electromechanical braking system according to any one of claims 1 to 11, characterized in that, The housing surface of the first wheel-end controller also includes a parking switch interface and a parking control interface. The parking switch interface is used to connect to the electronic parking brake system switch of the electric vehicle, and the parking control interface is used to connect to the electronic parking brake system switch of the electric vehicle. The first wheel-end controller is also used to control the electronic parking brake system of the electric vehicle to output parking braking force through the parking control interface.
13. The electromechanical braking system according to any one of claims 1 to 12, characterized in that, The housing surface of the first wheel-end controller also includes a wheel speed sensor interface, which is used to receive wheel speed signals from the wheel speed sensor, and the wheel speed signals are used to indicate the rotational speed of the wheels of the electric vehicle.
14. The electromechanical braking system according to any one of claims 1 to 13, characterized in that, The housing surface of the first wheel-end controller also includes a height sensor interface and a suspension control interface. The height sensor interface is used to connect to the height sensor of the electric vehicle, and the suspension control interface is used to connect to the suspension system of the electric vehicle. The first wheel-end controller is also used to control the suspension system to adjust the suspension damping according to the vehicle height indicated by the height sensor.
15. The electromechanical braking system according to any one of claims 1 to 14, characterized in that, The housing surface of the first wheel-end controller also includes a smart driving signal input interface. This interface receives smart driving signals from the smart driving controller of the electric vehicle. These signals are used to control the electric vehicle's drive system, braking system, and suspension system. The first wheel-end controller is used for: The intelligent driving signal indicates that the brakes in the four wheel-end braking devices are controlled to brake the four wheels of the electric vehicle.
16. An electric vehicle, characterized in that, The electric vehicle includes an electromechanical braking system for four wheels as described in any one of claims 1 to 15, the electromechanical braking system being used to output braking force to the wheels to brake the four wheels.