Torque control method and device for assisting driver in getting on and off and vehicle

Abstract

The invention provides a torque control method and device for assisting a driver in getting on and off and a vehicle. The method comprises the steps that under the condition that a driver getting on and off assisting function is activated and started, steering wheel sensor data and motor sensor data are obtained; based on the steering wheel sensor data and the motor sensor data, obtaining a driver input torque through a preset kinetic model used for estimating a torque used by a driver to rotate a steering wheel; the driver input torque is converted into a motor torque instruction, and the execution control system drives the motor to rotate reversely according to the motor torque instruction to generate counter-acting force to prevent the driver from rotating a steering wheel. A kinetic model is used for analyzing steering wheel sensor and motor sensor data to estimate driver input torque. When a driver gets on and gets off a vehicle, motor counterforce is output in real time according to torque input by the driver, so that the steering wheel can be intelligently controlled to be in a locked state, accidental rotation of the steering wheel is effectively prevented, and torque rebound is avoided.

Description

Technical Field

[0001] The present application relates to the technical field of wire-controlled steering, and in particular to a torque control method, device and vehicle for assisting a driver in getting on and off a vehicle. Background Art

[0002] With the development of the automobile industry, people have higher and higher requirements for automobile driving performance and convenience. In order to meet the needs of increasingly intelligent and diversified functions of automobiles, the steering system has also developed from mechanical steering, hydraulic steering, and electric power steering at the beginning to the current wire-controlled steering system. The wire-controlled steering system eliminates the mechanical intermediate shaft connecting the upper and lower parts of the traditional electric power steering system, decouples the upper steering wheel from the lower steering front wheel control system, and controls the steering wheel and the vehicle wheels through vehicle communication signals.

[0003] In order to help the driver maintain balance and stability during the process of getting on and off the vehicle, it is a common way to provide additional support to the driver by holding the steering wheel. Due to the characteristics of up and down decoupling of the wire control, there is no actual traditional tire friction transmitted to the steering wheel through the mechanical intermediate shaft. In some extreme cases, such as high torque release, when the driver applies a large torque on the steering wheel and lets go at high torque, the system may not be able to provide sufficient damping or braking force to prevent the steering wheel from bouncing off. The rapid rebound of the steering wheel will generate a huge impact force, which is not only transmitted to the driver through the steering wheel, causing injury to the driver, but may also directly damage the steering wheel and its connecting parts, and may even affect the stability of the entire wire control steering system. At the same time, in the case of high torque release, due to the excessive steering wheel rotation stroke, the steering wheel will rebound to a position beyond the normal operating range, thereby affecting the driver's control of the vehicle. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present application provides a torque control method, device and vehicle for assisting the driver in getting on and off the vehicle, aiming to solve the problems existing in the prior art.

[0005] In order to achieve the above purpose and other advantages, the present invention adopts the following technical solutions: In a first aspect, the present application provides a torque control method for assisting a driver in getting on or off a vehicle, comprising: When the driver entry and exit assistance function is activated, the steering wheel sensor data and motor sensor data are obtained; Based on the steering wheel sensor data and the motor sensor data, a driver input torque is obtained by using a preset dynamic model for estimating the torque used by the driver to turn the steering wheel; The driver input torque is converted into a motor torque command, and the execution control system drives the motor to reverse according to the motor torque command to generate a reaction force to prevent the driver from turning the steering wheel.

[0006] According to a torque control method for assisting a driver in getting on and off a vehicle provided in the present application, a dynamic model for estimating the torque used by the driver to turn the steering wheel is constructed, including: The mechanical structure of the road feel feedback assembly is simplified into a two-degree-of-freedom model including an upper column and a lower column. The upper column part is equivalent to the steering wheel at the upper end of the torsion bar, and a first differential equation of the upper column part is established, and the lower column part is equivalent to the gear at the lower end of the torsion bar, and a second differential equation of the lower column part is established; The state space equation is constructed by taking the rotation angle and rotation angular velocity of the steering wheel, the rotation angle and rotation angular velocity of the gear, and the driver's hand force as state variables, the motor torque as an input vector, and the torque of the driver turning the steering wheel as an output vector; Based on the first differential equation and the second differential equation, a system matrix of the state-space equation is obtained.

[0007] According to a torque control method for assisting a driver in getting on and off a vehicle provided by the present application, based on the steering wheel sensor data and the motor sensor data, a step of obtaining a driver input torque by using a preset dynamic model for estimating the torque used by the driver to turn the steering wheel comprises: The state space equation is observed by using a Kalman observer, and the state estimate at the previous moment is used to predict the state at the current moment, and at the same time, the error covariance at the current moment is predicted; Calculating a Kalman gain based on the predicted error covariance and the measurement noise covariance, wherein the Kalman gain is used to correct the weights of the predicted value and the current measurement value in updating the state estimation; Using the Kalman gain and the current measurement value, updating the state estimation value at the current moment and the error covariance at the current moment; The Kalman observer iteratively updates the state estimate according to new measurement data until an optimal estimate of the system state can be obtained in real time, wherein the optimal system state includes the driver input torque.

[0008] According to a torque control method for assisting a driver to get on and off a vehicle provided by the present application, before the step of activating the driver's getting on and off assist function, the method further includes: Determine whether to enable the driver's access assistance function according to preset conditions, wherein the preset conditions include: vehicle speed, gear position, parking status, game mode and smart driving mode; When the vehicle speed is zero, the gear is in P gear, the parking state is enabled, and the game mode and smart driving mode are not activated, the activation conditions of the driver's boarding and exiting assistance function are met, and an activation state signal with a value of 1 is output; When any one of the following conditions is not met: the vehicle speed is zero, the gear is in P gear, the parking state is enabled, the game mode is not activated, and the smart driving mode is not activated, the activation conditions of the driver's on and off assistance function are not met, and an activation status signal with a value of 0 is output.

[0009] According to a torque control method for assisting a driver in getting on and off a vehicle provided by the present application, the steering wheel sensor data includes: steering wheel angle, steering wheel speed and steering wheel torque, and the motor sensor data includes: motor angle, motor speed and motor torque; Before obtaining the driver input torque based on the steering wheel sensor data and the motor sensor data through a preset dynamic model for estimating the torque used by the driver to turn the steering wheel, the method further includes: The steering wheel sensor data and the motor sensor data are converted into units and filtered, the filtering effects are compared, and a suitable filter is selected to ensure that useful signals are retained while noise is removed.

[0010] A torque control method for assisting a driver in getting on and off a vehicle provided in the present application also includes: after the driver getting on and off assist function is completed, when there is an angle difference between the upper steering and the lower steering of the vehicle, an alignment instruction is sent to a corresponding steering mechanism for angle alignment.

[0011] According to a torque control method for assisting a driver in getting on and off a vehicle provided by the present application, signal transmission is performed between the upper steering and the lower steering via a data bus; When there is an angle difference between the upper steering and the lower steering of the vehicle, the step of performing angle alignment by sending an alignment instruction to the corresponding steering mechanism includes: The upper steering monitors the current angle state in real time, calculates the angle value that needs to be adjusted according to the difference between the target angle and the current angle, and generates a corresponding alignment instruction to be sent to the lower steering. After receiving the alignment instruction, the lower steering drives the steering mechanism to perform the steering operation until the target angle is reached.

[0012] In a second aspect, the present application provides a torque control device for assisting a driver in getting on or off a vehicle, comprising: A data acquisition module, used to acquire steering wheel sensor data and motor sensor data when the driver's access assistance function is activated; A driver torque estimation module, used to obtain a driver input torque based on the steering wheel sensor data and the motor sensor data by using a preset dynamic model for estimating the torque used by the driver to turn the steering wheel; A locking torque conversion module, used for converting the driver input torque into a motor torque command; The locking torque execution module is used to drive the motor to reverse according to the motor torque command, so as to generate a reaction force to prevent the driver from turning the steering wheel.

[0013] A torque control device for assisting a driver in getting on and off a vehicle provided by the present application also includes: An auxiliary function activation module is used to determine whether to turn on the driver's boarding and exiting assistance function according to preset conditions; A data preprocessing module, used to perform unit conversion and filtering on the steering wheel sensor data and the motor sensor data, compare filtering effects, and select a suitable filter to ensure that useful signals are retained while noise is removed; The angle alignment module is used to perform angle alignment by sending an alignment instruction to the corresponding steering mechanism when there is an angle difference between the upper steering and the lower steering of the vehicle.

[0014] In a third aspect, the present application provides a vehicle, comprising a torque control device as described in any one of the above for assisting a driver in getting on and off the vehicle.

[0015] The present application provides a torque control method, device and vehicle for assisting the driver to get on and off the vehicle. When the driver's on and off assist function is activated, the steering wheel sensor data and the motor sensor data are obtained; based on the steering wheel sensor data and the motor sensor data, the driver input torque is obtained through a preset dynamic model for estimating the torque used by the driver to turn the steering wheel; the driver input torque is converted into a motor torque instruction, and the execution control system drives the motor to reverse according to the motor torque instruction to generate a reaction force to prevent the driver from turning the steering wheel. The present application uses a dynamic model to analyze the steering wheel sensor and motor sensor data to estimate the driver's input torque. During the process of the driver getting on and off the vehicle, the motor reaction force is output in real time according to the driver's input torque, so that the steering wheel can be intelligently controlled to be in a locked state, effectively preventing accidental rotation of the steering wheel, and no torque rebound occurs, avoiding vehicle movement or safety hazards caused by steering wheel rebound. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other implementation methods can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 is a flow chart of a torque control method for assisting a driver in getting on and off a vehicle provided in an embodiment of the present application; Figure 2 Schematic diagram of the working process of the Kalman observer provided in the embodiment of the present application; Figure 3 It is a logical structure diagram of a torque control device for assisting a driver in getting on and off a vehicle provided in an embodiment of the present application. DETAILED DESCRIPTION

[0018] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the following specifically cites the preferred embodiments and describes them in detail with the accompanying drawings.

[0019] It should be noted that it is explicitly and implicitly understood by those of ordinary skill in the art that the embodiments described in this application can be combined with other embodiments without conflict. Unless otherwise defined, the technical terms or scientific terms involved in this application should be the usual meanings understood by people with ordinary skills in the technical field to which this application belongs. The words "one", "a", "a", "the" and the like involved in this application do not indicate a quantitative limitation and may represent the singular or plural. The terms "including", "comprising", "having" and any of their variations involved in this application are intended to cover non-exclusive inclusions; the terms "first", "second", "third", etc. involved in this application are merely to distinguish similar objects and do not represent a specific ordering of objects.

[0020] Embodiment 1 Reference Figure 1 As shown, the embodiment of the present application provides a torque control method for assisting a driver in getting on and off a vehicle, comprising: Step S1: When the driver's entry and exit assistance function is activated, the steering wheel sensor data and the motor sensor data are obtained.

[0021] In this embodiment, before step S1, the method further includes: Determine whether to enable the driver's access assistance function based on preset conditions, including vehicle speed, gear position, parking status, game mode, and smart driving mode; When the vehicle speed is zero, the gear is in P gear, the parking state is enabled, and the game mode and smart driving mode are not activated, the activation conditions of the driver's boarding and exiting assistance function are met, and an activation state signal with a value of 1 is output; When any one of the following conditions is not met: the vehicle speed is zero, the gear is in P gear, the parking state is enabled, the game mode is not activated, and the smart driving mode is not activated, the activation conditions of the driver's on and off assistance function are not met, and an activation status signal with a value of 0 is output.

[0022] Specifically, the vehicle speed must be zero to ensure that the vehicle is stationary to avoid mis-triggering the function while driving. The gear must be in P gear (parking gear) to further confirm that the vehicle has stopped. The parking state must be enabled, that is, the handbrake or electronic parking system is activated to ensure that the vehicle does not move accidentally. The game mode is inactive to prevent the actual vehicle control function from being mis-triggered in the game mode. Similarly, the smart driving mode is inactive to avoid conflicts with automatic driving or intelligent driving functions. When all the above conditions are met at the same time, the output value is 1. The activation state signal indicates that the driver's boarding and disembarking assistance function can be safely turned on; if any of the conditions is not met, the output value is 0. The activation state signal remains off. In this way, through the pre-condition judgment, it is ensured that the driver's boarding and disembarking assistance function is only enabled when the vehicle is completely stationary and in a safe state, avoiding safety hazards caused by misoperation or unexpected situations.

[0023] In this embodiment, the steering wheel sensor data includes: steering wheel angle, steering wheel speed and steering wheel torque, and the motor sensor data includes: motor angle, motor speed and motor torque.

[0024] Before step S2, the method further comprises: The steering wheel sensor data and motor sensor data are converted and filtered, the filtering effects are compared, and the appropriate filter is selected to ensure that useful signals are retained while noise is removed.

[0025] Among them, the motor angle and steering wheel angle are usually expressed in degrees (°) or radians (rad). The conversion relationship between degrees and radians is 360°=2π rad, that is, 1°= π / 180 rad. The international standard unit of motor speed and steering wheel speed is r / s (revolutions per second). In practical applications, it is often expressed in revolutions per minute (r / min) or angular velocity (ω / s, radians per second). The conversion relationship between revolutions per minute and revolutions per second is: divide the speed per minute by 60. The conversion relationship between angular velocity and is: ω = 2πn / 60 = πn / 30. The unit of motor torque and steering wheel torque is usually Newton meter (N·m).

[0026] Get the actual data of signals such as motor angle, motor speed, motor torque, steering wheel angle, steering wheel speed and steering wheel torque. You can apply low-pass, high-pass, band-pass and band-stop filters to process the signal data respectively. Evaluate the filtering effect by comparing the signal waveform, spectrum and other characteristics before and after filtering. According to the comparison of filtering effects, select the filter that can best remove noise while retaining useful signals. In this way, select the appropriate filter for processing according to the signal characteristics and noise conditions. Through filtering processing, the accuracy and reliability of the signal can be improved.

[0027] In this embodiment, a dynamic model for estimating the torque used by the driver to turn the steering wheel is constructed, specifically including: Step A1: Simplify the mechanical structure of the road feel feedback assembly into a two-degree-of-freedom model including an upper column part and a lower column part; Step A2: The upper column part is equivalent to the steering wheel at the upper end of the torsion bar, and the first differential equation of the upper column part is established, and the lower column part is equivalent to the gear at the lower end of the torsion bar, and the second differential equation of the lower column part is established; Step A3: The state space equation is constructed by taking the rotation angle and rotation angular velocity of the steering wheel, the rotation angle and rotation angular velocity of the gear, and the driver's hand force as state variables, the motor torque as an input vector, and the torque of the driver turning the steering wheel as an output vector; Step A4: Based on the first differential equation and the second differential equation, a system matrix of the state space equation is obtained.

[0028] Specifically, the mechanical structure of the road feel feedback assembly can be simplified into a two-degree-of-freedom model, namely, the upper column part and the lower column part. The upper column part and the lower column part. The upper column part includes components such as the steering wheel and the upper column, which are physically connected to each other and jointly participate in the driver's control of the vehicle. In the process of establishing the dynamic model, in order to simplify the model and reduce the amount of calculation, these components are usually equivalent to a single component, namely the steering wheel, represented by the symbol sw. The lower column part includes the motor, the pulley, and the lower column, which can also be equivalent to the gear, represented by the symbol pn. The torsion bar is a transmission component connecting the steering wheel and the gear, with its upper end connected to the steering wheel and the lower end connected to the gear. Therefore, the angle and angular velocity of the upper end of the torsion bar directly reflect the rotation state of the steering wheel, while the angle and angular velocity of the lower end directly reflect the rotation state of the gear. Therefore, by selecting the angle and angular velocity of these two points as state quantities, we can more intuitively understand and describe the dynamic behavior of the torsion bar and the components connected to it.

[0029] After dividing the degrees of freedom, the differential equation of the upper string is obtained as shown in formula (1): (1) in, is equivalent to the moment of inertia of the steering wheel, is the input steering torque on the steering wheel, i.e. the driver input torque, is the torsion bar damping coefficient, is the torsion bar stiffness coefficient, is the steering wheel rotation angle, is the steering wheel rotation angular velocity, is the gear rotation angle, is the gear rotation angular velocity, is the steering column damping coefficient.

[0030] And the differential equation of the lower pipe string is shown in formula (2): (2) in, is equivalent to the moment of inertia of the gear, is the motor torque, is the reduction ratio coefficient between the motor and the gear, is the torsion bar damping coefficient.

[0031] Select the angle of the steering wheel at the upper end of the torsion bar and angular velocity , the angle of the lower gear and angular velocity As a state variable, in order to input the driver torque As the disturbance input of the system, the integration link is used to estimate this disturbance so that it can be regarded as one of the state variables for estimation.

[0032] For the above two-degree-of-freedom model, the state vector x Defined as , the input vector u Defined as , the output vector Defined as , is the torsion bar torque, and the above differential equation is rewritten into the form of state space equation, as shown in equation (3): (3) Among them, the system matrix A , B , C and D They are:

[0033] in, is the torsion bar stiffness, is the reduction ratio of the reduction mechanism.

[0034] Step S2: Based on the steering wheel sensor data and the motor sensor data, the driver input torque is obtained by using a preset dynamic model for estimating the torque used by the driver to turn the steering wheel.

[0035] In this embodiment, step S2 specifically includes: Step S201: observe the state space equation using a Kalman observer, use the state estimate at the previous moment to predict the state at the current moment, and at the same time, predict the error covariance at the current moment; Step S202: Calculate the Kalman gain according to the predicted error covariance and the measurement noise covariance, where the Kalman gain is used to correct the weights of the predicted value and the current measured value in updating the state estimation; Step S203: using the Kalman gain and the current measurement value, updating the current state estimation value and the current error covariance; Step S204: The Kalman observer iteratively updates the state estimation value according to the new measurement data until the optimal estimation of the system state can be obtained in real time, where the optimal system state includes the driver input torque.

[0036] Specifically, after the state space equation of the road feel feedback assembly is established, a state observer or estimator is designed, which can estimate the internal state of the system, including disturbances, based on the input and output of the system. Exemplarily, a Kalman observer is used as a state observer. The driver input torque is a state variable in the state space equation, and its real-time value can be obtained through the estimation of the Kalman observer. The Kalman observer provides the optimal error estimate by combining the dynamic model of the system, the control input and the actual measurement.

[0037] like Figure 2 As shown in Figure 1, the Kalman observer demonstrates the two core steps of the Kalman filter: time update TimeUpdate (also called prediction) and measurement update Measurement Update (also called correction). By looping these two steps, the estimation accuracy of the state variables of the state space equation can be gradually improved.

[0038] First, based on the initial estimate (represents the estimated value of the system state at time k−1, which is used to predict the state of the system at time k status) and (It is the same as The related covariance matrix represents the uncertainty of the estimation error. This matrix will be used to calculate the covariance of the prediction error) Enter the time update phase: through the formula , using the state estimate at the previous moment to calculate the state prediction value at the current moment, where, Ais the state transfer matrix, B is the control input matrix, is the estimated value of the state at the previous moment, is the control input at the previous moment, The current state.

[0039] At the same time, through the formula , predict the error covariance at the current moment to assess the uncertainty of the predicted state. is the error covariance matrix of the previous moment, for A The transposed matrix of Q is the process noise covariance matrix, is the error covariance matrix at the current moment.

[0040] Next, we enter the measurement update phase: the Kalman gain is calculated based on the predicted error covariance and the measurement noise covariance. The Kalman gain is used to correct the weights of the predicted value and the current measured value in the updated state estimate. The calculation formula is: ,in H is the observation matrix, is the transposed matrix of the observation matrix, R is the measurement noise covariance matrix, is the Kalman gain.

[0041] By formula , using the Kalman gain and the current measurement value, update the state estimate at the current moment. is the current measured value, is the updated estimated value of the state at the current moment.

[0042] Finally, through the formula , update the error covariance matrix at the current moment to reflect the uncertainty of the updated state estimate.

[0043] The Kalman observer will repeat the process of steps S301 to S303 according to the new measurement data, and continuously iterate and update the state estimate. Through multiple iterations, the Kalman observer can gradually reduce the estimation error until it can obtain the optimal estimate of the system state in real time. These optimal system states include important parameters such as the driver input torque.

[0044] Step S3: Convert the driver's input torque into a motor torque command, and execute the control system to drive the motor to reverse according to the motor torque command to generate a reaction force to prevent the driver from turning the steering wheel.

[0045] Specifically, the estimated driver input torque is converted from a physical torque into an electrical signal, converted into a format that the control system can understand, and transmitted to the control system. The control system uses a preset algorithm (such as a PID control algorithm) to calculate the required motor torque command. This command is opposite to the direction of the driver's input torque, and the motor driver adjusts the motor speed and torque according to the command. The motor begins to reverse, generating a reaction force in the opposite direction of the driver's input torque. This force is transmitted to the driver through the steering wheel to offset the driver's input torque, thereby assisting the driver in getting on and off the vehicle.

[0046] In this embodiment, the method further includes: after the driver's boarding and exiting assistance function is completed, when there is an angle difference between the upper steering and the lower steering of the vehicle, an alignment instruction is sent to the corresponding steering mechanism to perform angle alignment. Signals are transmitted between the upper steering and the lower steering via a data bus. Specifically: The upper steering system monitors the current angle state in real time, calculates the angle value that needs to be adjusted based on the difference between the target angle and the current angle, and generates the corresponding alignment instruction to send to the lower steering system. After receiving the alignment instruction, the lower steering system drives the steering mechanism to perform the steering operation until the target angle is reached.

[0047] Specifically, the upper steering is used to receive the driver's steering intention and convert it into an electrical signal. The upper steering usually includes components such as a steering wheel, a torque sensor, and a steering angle sensor. The lower steering is used to control the steering of the wheels. This usually includes components such as a steering motor, a steering gear, and a steering rod. Between the upper steering and the lower steering, signals are usually transmitted through a data bus (such as a CAN network).

[0048] The upper and lower steering must work together to achieve precise steering control. The main controller (ECU module) plays a key role in this. It is responsible for analyzing and processing the signal from the upper steering, and calculating the desired wheel angle command based on the vehicle status, road conditions and other information, and then sending it to the lower steering for execution.

[0049] Since the driver manually intervenes in the steering wheel, this operation may be beyond the control range of the auxiliary function, or there is a calibration error in the steering actuator during the resetting process. Therefore, when the driver completes the on-and-off assistance function, there is an angle difference between the upper steering and the lower steering, and it is necessary to ensure the angle consistency between the upper and lower steering.

[0050] Angle alignment can be achieved by using the upper steering to send angle alignment instructions to the lower steering to align the lower steering. Specifically, the upper steering monitors the current angle state in real time through sensors (such as steering angle sensors). According to the difference between the target angle and the current angle, the upper steering calculates the angle value that needs to be adjusted and generates the corresponding alignment instructions, which are sent to the lower steering through a communication module (such as a data bus, wireless module, etc.). After receiving the instruction, the lower steering drives the steering mechanism (such as an electric motor, a servo motor) to perform the steering operation until the target angle is reached. The lower steering can be equipped with a position feedback device (such as an encoder, a potentiometer, etc.) to monitor the steering angle in real time and feed back the actual angle to the upper steering. The upper steering adjusts subsequent instructions based on the feedback information to achieve more accurate angle alignment.

[0051] Angle alignment can also be achieved by sending alignment instructions to the upper steering through the lower steering. The lower steering monitors the current angle state through sensors and determines whether the angle needs to be adjusted. If adjustment is required, the lower steering sends an adjustment request to the upper steering, and the request includes information such as the difference between the target angle and the current angle. After receiving the request from the lower steering, the upper steering generates an alignment instruction based on the request information. The upper steering sends the alignment instruction to the lower steering to instruct the lower steering to perform the steering operation until the target angle is reached. The sending and execution of the alignment instruction needs to meet certain timing and synchronization requirements to ensure that the actuator can execute the instruction in a timely and accurate manner, thereby achieving precise angle alignment.

[0052] In summary, the torque control method, device and vehicle for assisting the driver to get on and off the vehicle provided by the embodiment of the present application, when the driver's getting on and off assist function is activated, obtains the steering wheel sensor data and the motor sensor data; based on the steering wheel sensor data and the motor sensor data, obtains the driver's input torque through a preset dynamic model for estimating the torque used by the driver to turn the steering wheel; converts the driver's input torque into a motor torque command, and the execution control system drives the motor to reverse according to the motor torque command to generate a reaction force to prevent the driver from turning the steering wheel. The present application uses a dynamic model to analyze the steering wheel sensor and motor sensor data to estimate the driver's input torque. During the process of the driver getting on and off the vehicle, the motor reaction force is output in real time according to the driver's input torque, so that the steering wheel can be intelligently controlled to be in a locked state, effectively preventing accidental rotation of the steering wheel, and no torque rebound occurs, thereby avoiding vehicle movement or safety hazards caused by steering wheel rebound.

[0053] Those skilled in the art will appreciate that, in the above method of specific implementation, the order in which the steps are written does not imply a strict execution order and does not constitute any limitation on the implementation process. The specific execution order of the steps should be determined by their functions and possible internal logic.

[0054] Embodiment 2 Based on the method of embodiment 1, this embodiment provides a torque control device for assisting a driver to get on and off a vehicle, which is used to implement the method of embodiment 1. The torque control device for assisting a driver to get on and off a vehicle provided by the present application is described below, and the torque control method for assisting a driver to get on and off a vehicle described above can be referred to in correspondence with each other.

[0055] Reference Figure 3 As shown, an embodiment of the present application provides a torque control device for assisting a driver in getting on and off a vehicle, comprising: A data acquisition module, used to acquire steering wheel sensor data and motor sensor data when the driver's access assistance function is activated; A dynamic model building module, used to build a dynamic model for estimating the torque used by the driver to turn the steering wheel based on the steering wheel sensor data and the motor sensor data; A driver torque estimation module, used for estimating the driver input torque based on the dynamic model; A locking torque conversion module, used for converting the driver input torque into a motor torque command; The locking torque execution module is used to drive the motor to reverse according to the motor torque command, so as to generate a reaction force to prevent the driver from turning the steering wheel.

[0056] In this embodiment, the device further includes: An auxiliary function activation module is used to determine whether to turn on the driver's boarding and exiting assistance function according to preset conditions; A data preprocessing module, used to perform unit conversion and filtering on the steering wheel sensor data and the motor sensor data, compare filtering effects, and select a suitable filter to ensure that useful signals are retained while noise is removed; The angle alignment module is used to perform angle alignment by sending an alignment instruction to the corresponding steering mechanism when there is an angle difference between the upper steering and the lower steering of the vehicle.

[0057] It should be noted that, for other corresponding descriptions of the functional modules involved in the torque control device for assisting a driver in getting on and off a vehicle provided in this embodiment, reference can be made to the corresponding descriptions in the first embodiment, which will not be repeated here.

[0058] Based on the above-mentioned torque control device for assisting the driver to get on and off the vehicle, the embodiment of the present application further provides a vehicle, which may specifically include the torque control device for assisting the driver to get on and off the vehicle. The vehicle may specifically be a passenger car, a commercial vehicle, an off-road vehicle, or a special-purpose vehicle. For vehicles with higher bodies, the inconvenience of getting on and off the vehicle is more obvious. Incorporating the function of assisting getting on and off the vehicle into its intelligent system improves the user experience. This design is particularly considerate for people with limited mobility or the elderly.

[0059] The flow chart or block diagram in the accompanying drawings shows the possible architecture, function and operation of the equipment, method and computer program product according to various embodiments of the present application. In this regard, each box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flow chart, and the combination of the boxes in the block diagram and / or flow chart can be implemented with a dedicated system for hardware that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0060] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily mention changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims, and the above embodiments should be regarded as exemplary and non-restrictive.

Claims

1. A torque control method for assisting a driver in getting on or off a vehicle, characterized in that: include: When the driver entry and exit assistance function is activated, the steering wheel sensor data and motor sensor data are obtained; Based on the steering wheel sensor data and the motor sensor data, a driver input torque is obtained by using a preset dynamic model for estimating the torque used by the driver to turn the steering wheel; Build a dynamic model to estimate the torque applied by the driver to turn the steering wheel, including: The mechanical structure of the road feel feedback assembly is simplified into a two-degree-of-freedom model including an upper column and a lower column. The upper column part is equivalent to the steering wheel at the upper end of the torsion bar, and a first differential equation of the upper column part is established, and the lower column part is equivalent to the gear at the lower end of the torsion bar, and a second differential equation of the lower column part is established; The state space equation is constructed by taking the rotation angle and rotation angular velocity of the steering wheel, the rotation angle and rotation angular velocity of the gear, and the driver's hand force as state variables, the motor torque as an input vector, and the torque of the driver turning the steering wheel as an output vector; Based on the first differential equation and the second differential equation, obtaining a system matrix of the state space equation; The driver input torque is converted into a motor torque command, and the execution control system drives the motor to reverse according to the motor torque command to generate a reaction force to prevent the driver from turning the steering wheel.

2. The torque control method for assisting a driver in getting on and off a vehicle according to claim 1, characterized in that: The step of obtaining the driver input torque based on the steering wheel sensor data and the motor sensor data through a preset dynamic model for estimating the torque used by the driver to turn the steering wheel comprises: The state space equation is observed by using a Kalman observer, and the state estimate at the previous moment is used to predict the state at the current moment, and at the same time, the error covariance at the current moment is predicted; Calculating a Kalman gain based on the predicted error covariance and the measurement noise covariance, wherein the Kalman gain is used to correct the weights of the predicted value and the current measurement value in updating the state estimation; Using the Kalman gain and the current measurement value, updating the state estimation value at the current moment and the error covariance at the current moment; The Kalman observer iteratively updates the state estimate according to new measurement data until an optimal estimate of the system state can be obtained in real time, wherein the optimal system state includes the driver input torque.

3. The torque control method for assisting a driver in getting on and off a vehicle according to claim 1, characterized in that: Before the steps when the driver entry and exit assistance function is activated, it also includes: Determine whether to enable the driver's access assistance function according to preset conditions, wherein the preset conditions include: vehicle speed, gear position, parking status, game mode and smart driving mode; When the vehicle speed is zero, the gear is in P gear, the parking state is enabled, and the game mode and smart driving mode are not activated, the activation conditions of the driver's boarding and exiting assistance function are met, and an activation state signal with a value of 1 is output; When any one of the following conditions is not met: the vehicle speed is zero, the gear is in P gear, the parking state is enabled, the game mode is not activated, and the smart driving mode is not activated, the activation conditions of the driver's on and off assistance function are not met, and an activation status signal with a value of 0 is output.

4. The torque control method for assisting a driver in getting on and off a vehicle according to claim 1, characterized in that: The steering wheel sensor data includes: steering wheel angle, steering wheel speed and steering wheel torque; the motor sensor data includes: motor angle, motor speed and motor torque; Before obtaining the driver input torque based on the steering wheel sensor data and the motor sensor data through a preset dynamic model for estimating the torque used by the driver to turn the steering wheel, the method further includes: The steering wheel sensor data and the motor sensor data are converted into units and filtered, the filtering effects are compared, and a suitable filter is selected to ensure that useful signals are retained while noise is removed.

5. The torque control method for assisting a driver in getting on and off a vehicle according to claim 1, characterized in that: Also includes: After the driver's on-and-off assist function is completed, when there is an angle difference between the upper steering and the lower steering of the vehicle, an alignment instruction is sent to the corresponding steering mechanism to perform angle alignment.

6. The torque control method for assisting a driver in getting on and off a vehicle according to claim 5, characterized in that: Signal transmission is performed between the upper steering and the lower steering via a data bus; When there is an angle difference between the upper steering and the lower steering of the vehicle, the step of performing angle alignment by sending an alignment instruction to the corresponding steering mechanism includes: The upper steering monitors the current angle state in real time, calculates the angle value that needs to be adjusted according to the difference between the target angle and the current angle, and generates a corresponding alignment instruction to be sent to the lower steering. After receiving the alignment instruction, the lower steering drives the steering mechanism to perform the steering operation until the target angle is reached.

7. A torque control device for assisting a driver in getting on or off a vehicle, characterized in that: include: A data acquisition module, used to acquire steering wheel sensor data and motor sensor data when the driver's access assistance function is activated; A driver torque estimation module, used to obtain a driver input torque based on the steering wheel sensor data and the motor sensor data by using a preset dynamic model for estimating the torque used by the driver to turn the steering wheel; Among them, a dynamic model for estimating the torque used by the driver to turn the steering wheel is constructed, including: The mechanical structure of the road feel feedback assembly is simplified into a two-degree-of-freedom model including an upper column and a lower column. The upper column part is equivalent to the steering wheel at the upper end of the torsion bar, and a first differential equation of the upper column part is established, and the lower column part is equivalent to the gear at the lower end of the torsion bar, and a second differential equation of the lower column part is established; The state space equation is constructed by taking the rotation angle and rotation angular velocity of the steering wheel, the rotation angle and rotation angular velocity of the gear, and the driver's hand force as state variables, the motor torque as an input vector, and the torque of the driver turning the steering wheel as an output vector; Based on the first differential equation and the second differential equation, obtaining a system matrix of the state space equation; A locking torque conversion module, used for converting the driver input torque into a motor torque command; The locking torque execution module is used to drive the motor to reverse according to the motor torque command, so as to generate a reaction force to prevent the driver from turning the steering wheel.

8. The torque control device for assisting a driver in getting on and off a vehicle according to claim 7, characterized in that: Also includes: An auxiliary function activation module is used to determine whether to turn on the driver's boarding and exiting assistance function based on preset conditions; A data preprocessing module, used to perform unit conversion and filtering on the steering wheel sensor data and the motor sensor data, compare filtering effects, and select a suitable filter to ensure that useful signals are retained while noise is removed; The angle alignment module is used to perform angle alignment by sending an alignment instruction to the corresponding steering mechanism when there is an angle difference between the upper steering and the lower steering of the vehicle.

9. A vehicle, characterized in that: The invention comprises a torque control device for assisting a driver in getting on or off a vehicle as claimed in claim 7 or 8.

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