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CN-117565964-B - Vehicle steering power-assisted active adjustment control system

CN117565964BCN 117565964 BCN117565964 BCN 117565964BCN-117565964-B

Abstract

The invention discloses a vehicle steering assistance active regulation control system which comprises a vehicle running attitude angle collecting unit, a vehicle running attitude angle resolving unit, a steering assistance mode switching control unit and a steering assistance correction control unit. The vehicle running attitude angle collecting unit is used for obtaining a running vehicle body side deviation angle, a running vehicle body side inclination angle, a running vehicle body swing angle and a running vehicle body pitch angle, the vehicle running attitude angle resolving unit comprises a vehicle body attitude multi-state matrix resolving function, an attitude angle resolving coefficient is designed, an attitude angle threshold value distinguishing weight coefficient is designed to obtain an attitude angle evaluating factor of current vehicle running, the steering assistance mode switching control unit comprises a running attitude safety mode, a running attitude comfort mode and a running attitude movement mode, and the steering assistance correction control unit matches a steering assistance controller with the attitude conversion control factor of the current vehicle according to different steering assistance modes to correct and control the steering assistance.

Inventors

  • ZHANG HONGKUN
  • FAN MINGQIANG
  • ZHENG HONGYU
  • CHEN CHENGJIE

Assignees

  • 吉林大学

Dates

Publication Date
20260505
Application Date
20231121

Claims (9)

  1. 1. The vehicle steering power-assisted active regulation control system is characterized by comprising a vehicle running attitude angle collecting unit, a vehicle running attitude angle resolving unit, a steering power-assisted mode switching control unit and a steering power-assisted correction control unit; The vehicle running attitude angle collecting unit comprises a longitudinal attitude angle collecting unit, a transverse attitude angle collecting unit and a jump attitude angle collecting unit, wherein the longitudinal attitude angle collecting unit comprises a vehicle body side deflection angle sensor for acquiring a running vehicle body side deflection angle beta, the transverse attitude angle collecting unit comprises a running vehicle body side deflection angle sensor for acquiring a running vehicle body side deflection angle sigma, a vehicle body yaw angle sensor for acquiring a running vehicle body swing angle phi, and the jump attitude angle collecting unit comprises a vehicle body pitch angle sensor for acquiring a running vehicle body pitch angle delta; The vehicle running attitude angle resolving unit comprises a vehicle body attitude multi-state matrix resolving function, a vehicle body attitude multi-state model resolving unit and a vehicle body attitude multi-state model resolving unit, wherein the vehicle body attitude multi-state matrix resolving function is used for obtaining a current vehicle running attitude angle; The body posture multi-state matrix solving function is shown as follows, kc=kc(κ 1 ,κ 2 ,κ 3 ), Wherein, kappa 1 is a longitudinal attitude angle, kappa 2 is a transverse attitude angle, kappa 3 is a jump attitude angle, and kc is a matrix state of vehicle running attitude angles; The matrix state design attitude angle threshold value of the vehicle running attitude angle distinguishes the weight coefficient gamma to obtain the attitude angle evaluation factor lambda of the current vehicle running, λ=γ*kc, Wherein kc is a matrix state of a vehicle running attitude angle, and gamma is an attitude angle threshold distinguishing weight coefficient; The steering power-assisted mode switching control unit comprises a driving gesture safety mode, a driving gesture comfort mode and a driving gesture movement mode, wherein the driving gesture safety mode, the driving gesture comfort mode and the driving gesture movement mode are used for evaluating that the current vehicle is in different modes according to different intervals of the gesture angle evaluation factor compared with the stability degree of the driving gesture of the current vehicle, the steering power-assisted correction control degree required by the different modes is different, the gesture conversion control factors χ corresponding to the different modes are different, the gesture conversion control factors χ suitable for the driving state of the current vehicle are obtained, Wherein, beta 0 is a vehicle body side deflection angle vector, sigma 0 is a vehicle body side inclination angle vector, phi 0 is a vehicle body swing angle vector, delta 0 is a vehicle body pitch angle vector, t 1 is a longitudinal attitude angle resolving coefficient, t 2 is a transverse attitude angle resolving coefficient, t 3 is a jump attitude angle resolving coefficient, Calculating a function matrix state for the body posture multi-state matrix; the attitude conversion control factor χ is used for inputting a steering assistance correction control unit to correct steering assistance under the current running attitude mode of the vehicle; The power-assisted steering correction control unit evaluates that the vehicle is in different power-assisted steering modes according to the magnitude of an attitude angle evaluation factor lambda of the current vehicle, analyzes the running attitude of the current vehicle, and carries out linear adjustment power-assisted steering and optimization of the attitude angle evaluation factor lambda by matching with power-assisted steering controllers in different self-defined running attitude modes according to an attitude conversion control factor χ of the current vehicle so as to carry out correction control on the power-assisted steering.
  2. 2. The vehicle steering assist active adjustment control system according to claim 1, wherein the vehicle running attitude angle resolving unit performs preliminary resolving by referring to a designed longitudinal attitude angle resolving coefficient, a designed transverse attitude angle resolving coefficient, and a jump attitude angle resolving coefficient; According to the vehicle body slip angle beta collected by a vehicle body slip angle sensor in the longitudinal attitude angle collecting unit, the value of a longitudinal attitude angle calculating coefficient t 1 ,т 1 is determined by the current slip degree of the vehicle, the range is limited to be 0< t 1 <1, the smaller the value is, the greater the current vehicle body slip degree is, otherwise, the current vehicle longitudinal running is stable, and the vehicle body slip degree is small; According to the longitudinal attitude angle calculating method, a corresponding longitudinal attitude angle calculating coefficient T 1 is given to the side deviation angle beta of the running vehicle body, and the longitudinal attitude angle kappa 1 is obtained through calculating: Wherein kappa 1 is a longitudinal attitude angle, t 1 is a longitudinal attitude angle calculation coefficient, and beta is a traveling vehicle body slip angle; According to the vehicle body roll angle sigma collected by the vehicle body roll angle sensor in the transverse attitude angle collecting unit, the vehicle body roll angle phi collected by the vehicle body roll angle sensor, the value of the transverse attitude angle resolving coefficient 2 ,т 2 is determined by the current roll degree and the yaw degree of the vehicle, the range is limited to 0< 2 <1, the smaller value indicates that the current vehicle body roll and the roll degree are larger, otherwise, the current vehicle transverse running is stable, and the vehicle body roll degree is small; According to the transverse attitude angle calculating method, corresponding transverse attitude angle calculating coefficients t 2 are given to the side inclination angle sigma of the running vehicle body and the swinging angle phi of the running vehicle body, and the transverse attitude angle kappa 2 is obtained through calculating: Wherein, κ 2 is a transverse attitude angle, t 2 is a transverse attitude angle calculation coefficient, σ is a vehicle body roll angle, Φ is a vehicle body swing angle, and the angle relationship between the vehicle body roll angle σ and the vehicle body swing angle Φ in the same plane should be considered when calculating the transverse attitude angle κ 2 ; according to the running vehicle body pitch angle delta collected by a vehicle body pitch angle sensor in the jump attitude angle collecting unit, the value of the jump attitude angle calculating coefficient Tf 3 ,т 3 is determined by the current pitching degree of the vehicle, the range is limited to be 0< 3 <1, the smaller the value is, the more obvious the current vehicle body vertical jump is, the greater the pitching degree is, otherwise, the current vehicle vertical running is stable, and the vehicle body pitching degree is small; According to the jump attitude angle calculating method, a corresponding jump attitude angle calculating coefficient T 3 is given to the pitch angle delta of the running vehicle body, and the jump attitude angle kappa 3 is obtained through calculation: Wherein κ 3 is the jump attitude angle, t 3 is the jump attitude angle calculation coefficient, and δ is the pitch angle of the vehicle body.
  3. 3. The vehicle steering assist active adjustment control system according to claim 2, wherein the vehicle running attitude angle calculation unit completes preliminary calculation of a longitudinal attitude angle κ 1 , a lateral attitude angle κ 2 , and a jump attitude angle κ 3 , and designs a vehicle body attitude multi-state matrix calculation function: Wherein, κ 1 is a longitudinal attitude angle, κ 2 is a transverse attitude angle, κ 3 is a jump attitude angle, β is a running vehicle body side deviation angle, σ is a running vehicle body side inclination angle, Φ is a running vehicle body roll angle, δ is a running vehicle body pitch angle, β 0 is a running vehicle body side deviation angle vector, σ 0 is a running vehicle body side inclination angle vector, Φ 0 is a running vehicle body roll angle vector, δ 0 is a running vehicle body pitch angle vector, and vectorization of angles is a direction treatment giving a function; The function matrix is stateized, and mathematical operation is performed to obtain the current matrix state kc of the vehicle running attitude angle, and the steps are as follows: Step 1, function matrix normalization: step 2, carrying out mathematical operation by using the attitude angle calculation coefficient: Wherein, Q is a matrix form of attitude angle resolving coefficients, t 1 is a longitudinal attitude angle resolving coefficient, t 2 is a transverse attitude angle resolving coefficient, t 3 is a jump attitude angle resolving coefficient; Obtaining the matrix state of the vehicle running attitude angle Wherein, the
  4. 4. The vehicle steering assist active adjustment control system according to claim 3, wherein the vehicle running posture angle calculating unit obtains a matrix-state vehicle running posture angle by using a vehicle body posture multi-state matrix calculating function, and performs mathematical processing on a current vehicle running posture angle to evaluate a current running posture of the vehicle; the weight coefficient gamma is distinguished by the threshold value of the attitude angle, and the matrix state kc of the current vehicle running attitude angle can be processed: kc=[h 1 (κ) h 2 (κ) h 3 (κ) h 4 (κ)] T , According to the attitude angle threshold region resolving method, a weight coefficient gamma is given to the running attitude angle of the vehicle in the current matrix state: λ=γ*kc, wherein, gamma is the weight coefficient calculated by decomposing the attitude angle threshold region, And calculating to obtain an attitude angle evaluation factor lambda, wherein the attitude angle evaluation factor lambda is used for evaluating the current running attitude of the vehicle.
  5. 5. The vehicle steering assist active adjustment control system according to claim 3, wherein the magnitude of the attitude angle evaluation factor λ obtained by the vehicle running attitude angle calculation unit determines the stability of the current vehicle running attitude, the range of the attitude angle evaluation factor λ is 0< λ <1, and the greater the value of the attitude angle evaluation factor λ, the more unstable the current vehicle running attitude is, i.e., the greater the probability of running dangerous accident is; Setting the value of an attitude angle evaluation factor lambda as a section 1 at 0< lambda less than or equal to 0.3, setting the value of the attitude angle evaluation factor lambda as a section 2 at 0.3< lambda less than or equal to 0.6, setting the value of the attitude angle evaluation factor lambda as a section 3 at 0.6< lambda less than or equal to 0.9, setting the value of the attitude angle evaluation factor lambda as a section 4, taking a vehicle running dangerous state when the condition of the section 4 occurs, adopting a vehicle alarming emergency regulation measure, enabling the vehicle to cooperate with a braking system to act in a short time, regulating a suspension, increasing steering assistance until the running posture is stable, and reducing the value of the attitude angle evaluation factor lambda to be within the sections 1 to 3 so as to prevent the instability of the vehicle body.
  6. 6. The vehicle steering assist active adjustment control system according to claim 1, wherein the steering assist mode switching control unit includes a running posture safety mode, a running posture comfort mode, a running posture movement mode, and a posture angle evaluation factor λ value different in different regions corresponding to a current running posture of the vehicle, and the required steering assist force is different; According to the size of the attitude angle evaluation factor lambda, the current vehicle is evaluated to be in different modes, and the steering assistance correction control degrees required by the different modes are different; The steering power-assisted correction control unit is used for linearly adjusting steering power by using proportional and integral closed-loop feedback control, and simultaneously is controlled by a posture conversion control factor χ so that the current running mode of the vehicle obtains proper steering power.
  7. 7. The vehicle steering assist active adjustment control system according to claim 6, wherein the vehicle running posture angle calculating unit obtains that the magnitude of the posture angle evaluation factor λ is in a section 3, and the steering assist mode switching control unit adopts a running posture movement mode to make a judgment on the current vehicle running posture: The lambda value is in a section 3, if the value of a longitudinal attitude angle kappa 1 is 0.7< kappa 1 <1 at the moment, the current vehicle running is judged to be in a large cornering attitude, the current longitudinal attitude conversion control factor chi β is calculated by the running vehicle body cornering angle beta collected by the longitudinal attitude angle collecting unit in the vehicle running attitude angle collecting unit, and the control correction of steering power is regulated, so that the aims of reducing the vehicle body cornering degree and stabilizing the vehicle longitudinal running attitude are fulfilled; the steering assistance correction control unit designs a longitudinal posture conversion control factor for obtaining steering assistance required to be controlled for correcting the stability of the running longitudinal posture of the vehicle: Wherein χ β is a longitudinal attitude conversion control factor, beta 0 is a running body slip angle vector, Calculating a function matrix state for a vehicle body posture multi-state matrix, wherein t 1 is a longitudinal posture angle calculating coefficient; the longitudinal steering power-assisted controller based on the linear adjustment of the large cornering attitude is designed, and the control distribution problem based on the proportion and the integral can be converted into the following optimization problem: Wherein χ β is a longitudinal attitude conversion control factor, Q is a matrix form of an attitude angle calculation coefficient, τ y is a corrected steering assistance, kc is a matrix state of a vehicle running attitude angle, and F y ＝[F y1 F y2 F y3 F y4 is a tire longitudinal force vector; If the value of the transverse attitude angle kappa 2 is 0.7< kappa 2 <1, judging that the current vehicle is in a large yaw attitude, calculating the current transverse attitude conversion control factor χ Ф by the lateral inclination angle sigma and the swing angle phi of the vehicle body collected by the transverse attitude angle collecting unit in the vehicle traveling attitude angle collecting unit, and adjusting the control correction of steering assistance to achieve the purposes of reducing the transverse swing and the side inclination degree of the vehicle body and stabilizing the transverse traveling attitude of the vehicle body; the steering assistance correction control unit designs a transverse attitude conversion control factor for obtaining steering assistance required to be controlled for correcting the stability of the running transverse attitude of the vehicle: wherein χ Ф is a transverse posture conversion control factor, σ 0 is a vehicle body roll angle vector, phi 0 is a vehicle body swing angle vector, Calculating a function matrix state for a vehicle body posture multi-state matrix, wherein t 2 is a transverse posture angle calculating coefficient; the design of the transverse steering power-assisted controller based on the linear adjustment of the large yaw attitude can be converted into the following optimization problem based on the control distribution problem of proportion and integral: Wherein χ Ф is a transverse attitude conversion control factor, Q is a matrix form of an attitude angle calculation coefficient, τ x is a corrected steering assistance, kc is a matrix state of a vehicle running attitude angle, and F x ＝[F x1 F x2 F x3 F x4 is a transverse force vector; If the value of the jump attitude angle kappa 3 is 0.7< kappa 3 <1, judging that the current vehicle running is in a large pitch attitude, and calculating the pitch angle delta of the running vehicle body collected by the jump attitude angle collecting unit in the vehicle running attitude angle collecting unit to obtain a current longitudinal attitude conversion control factor chi δ , and adjusting the control correction of steering power to achieve the purposes of reducing the pitch degree of the vehicle body and stabilizing the vertical running attitude of the vehicle body; the steering assistance correction control unit designs a jump gesture conversion control factor for obtaining steering assistance required to be controlled for correcting the stable running vertical gesture of the vehicle: wherein χ δ is a jump attitude conversion control factor, delta 0 is a running vehicle body pitch angle vector, Calculating a function matrix state for a vehicle body posture multi-state matrix, wherein t 3 is a jump posture angle calculating coefficient; the vertical steering power-assisted controller based on large pitch attitude linear adjustment is designed, and the control distribution problem based on proportion and integration can be converted into the following optimization problem: Wherein χ δ is a jump attitude conversion control factor, Q is a matrix form of an attitude angle calculation coefficient, τ z is a corrected steering assist force, kc is a matrix state of a vehicle running attitude angle, and F z ＝[F z1 F z2 F z3 F z4 is a vertical force vector.
  8. 8. The vehicle steering assist active adjustment control system according to claim 6, wherein the vehicle running posture angle calculating unit obtains that the magnitude of the posture angle evaluation factor λ is in a section 2, the steering assist mode switching control unit adopts a running posture comfort mode, and makes a judgment on the current vehicle running posture: if the value of the longitudinal attitude angle kappa 1 is more than or equal to 0.4 and less than or equal to kappa 1 and less than or equal to 0.7 at the moment, judging that the current vehicle is in a middle lateral deviation attitude, and calculating the current longitudinal attitude conversion control factor chi β by the lateral deviation angle beta of the vehicle body collected by a longitudinal attitude angle collecting unit in the vehicle traveling attitude angle collecting unit, wherein the steering assistance is corrected according to the value of the attitude angle evaluation factor lambda, so that the aims of reducing the lateral deviation degree of the vehicle body and stabilizing the longitudinal traveling attitude of the vehicle body are fulfilled; the longitudinal steering power-assisted controller based on the linear adjustment of the middle-side deviation posture is designed, and the control distribution problem based on the proportion and the integral of the middle-side deviation posture can be converted into the optimization problem of the following related posture angle evaluation factor lambda: lambda is more than or equal to 0.4 and less than or equal to 0.55: 0.55< lambda≤0.7: Wherein λ is an attitude angle evaluation factor, χ β is a longitudinal attitude conversion control factor, Q is a matrix form of an attitude angle calculation coefficient, τ y is a corrected steering assist force, kc is a matrix state of a vehicle running attitude angle, and F y ＝[F y1 F y2 F y3 F y4 is a tire longitudinal force vector; If the value of the transverse attitude angle kappa 2 is more than or equal to 0.4 and less than or equal to kappa 2 and less than or equal to 0.7 at the moment, judging that the current vehicle is in a middle yaw attitude, and calculating the current transverse attitude conversion control factor χ Ф by the lateral inclination angle sigma and the swing angle phi of the vehicle body collected by the transverse attitude angle collecting unit in the vehicle traveling attitude angle collecting unit, wherein the steering assistance is corrected according to the value of the attitude angle evaluation factor lambda, so that the aims of reducing the transverse swing and the rolling degree of the vehicle body and stabilizing the transverse traveling attitude of the vehicle body are fulfilled; The transverse steering power-assisted controller based on the linear adjustment of the middle yaw attitude is designed, and the control distribution problem based on the proportion and integration of the middle yaw attitude can be converted into the optimization problem of the following related attitude angle evaluation factor lambda: lambda is more than or equal to 0.4 and less than or equal to 0.55: 0.55< lambda≤0.7: Wherein λ is an attitude angle evaluation factor, χ Ф is a transverse attitude conversion control factor, Q is a matrix form of an attitude angle calculation coefficient, τ x is a corrected steering assist force, kc is a matrix state of a vehicle running attitude angle, and F x ＝[F x1 F x2 F x3 F x4 is a transverse force vector; If the value of the jump attitude angle kappa 3 is more than or equal to 0.4 and less than or equal to kappa 3 and less than or equal to 0.7 at the moment, judging that the current vehicle is in a medium pitch attitude, and calculating the pitch angle delta of the running vehicle body collected by the jump attitude angle collecting unit in the vehicle running attitude angle collecting unit to obtain a current jump attitude conversion control factor chi δ , and correcting steering assistance according to the value of the attitude angle evaluation factor lambda at the moment, so that the purposes of reducing the pitch degree of the vehicle body and stabilizing the vertical running attitude of the vehicle body are achieved; The vertical steering power-assisted controller based on the linear adjustment of the medium pitch attitude is designed, and the control distribution problem based on the proportion and the integral of the medium pitch attitude can be converted into the optimization problem of the following related attitude angle evaluation factor lambda: lambda is more than or equal to 0.4 and less than or equal to 0.55: 0.55< lambda≤0.7: wherein λ is an attitude angle evaluation factor, χ δ is a jump attitude conversion control factor, Q is a matrix form of an attitude angle calculation coefficient, τ z is a corrected steering assist force, kc is a vehicle running attitude angle matrix state, and F z ＝[F z1 F z2 F z3 F z4 is a vertical force vector.
  9. 9. The vehicle steering assist active adjustment control system according to claim 1, wherein the vehicle running posture angle calculating unit obtains that the magnitude of the posture angle evaluation factor λ is in a range 1, the steering assist mode switching control unit adopts a running posture safety mode, and makes a judgment on the current vehicle running posture: If the value of the longitudinal attitude angle kappa 1 is 0< kappa 1 <0.4 at the moment, judging that the current vehicle is in a small lateral deviation attitude, and ensuring that the vehicle is in a safe running state and the longitudinal running attitude is stable; If the value of the transverse attitude angle kappa 2 is 0< kappa 2 <0.4 at the moment, judging that the current vehicle is in a small yaw attitude, and the vehicle is in a safe running state at the moment, and the transverse running attitude is stable; If the value of the jump attitude angle kappa 3 is 0< kappa 3 <0.4, the current running of the vehicle is judged to be in a small pitch attitude, the vehicle is in a safe running state, and the jump running attitude is stable.

Description

Vehicle steering power-assisted active adjustment control system Technical Field The invention relates to an active steering power-assisted adjustment control system for a vehicle. Background Along with the increasing degree of intellectualization of modern automobile technology, the intellectualization of automobile steering power is also becoming the focus of research gradually. In recent years, as people call for safety, intelligence and energy conservation more and more, an electric power steering system of an automobile is popular in the industry as an on-demand steering mechanism, and represents the development direction of the steering technology of the automobile in the future. The motor output characteristic of the electric power steering system can be precisely controlled through programming, so that a plurality of new functions can be realized in an expanding way, and the active adjustment of the steering power is one of the functions. However, for the stability of the running of the automobile and the comfort of the driver, the active adjustment control of the steering assistance needs to consider the running gesture and gesture conversion control factor of the current automobile, so how to effectively ensure the stability of the running gesture of the automobile and evaluate the current running gesture to actively adjust the steering assistance becomes a technical problem to be solved urgently by the applicant. To improve these problems, the invention provides an active steering control system for a vehicle. Disclosure of Invention The invention aims to provide an active steering control system for a vehicle, which solves the problems in the background art. In order to achieve the purpose, the invention provides the technical scheme that the vehicle steering assistance active adjustment control system comprises a vehicle running attitude angle collecting unit, a vehicle running attitude angle resolving unit, a steering assistance mode switching control unit and a steering assistance correction control unit. The vehicle running attitude angle collecting unit comprises a longitudinal attitude angle collecting unit, a transverse attitude angle collecting unit and a jump attitude angle collecting unit, wherein the longitudinal attitude angle collecting unit comprises a vehicle body side deflection angle sensor for acquiring a running vehicle body side deflection angle beta, the transverse attitude angle collecting unit comprises a running vehicle body side deflection angle sensor for acquiring a running vehicle body side deflection angle sigma, a vehicle body yaw angle sensor for acquiring a running vehicle body swing angle phi, and the jump attitude angle collecting unit comprises a vehicle body pitch angle sensor for acquiring a running vehicle body pitch angle delta; The vehicle running attitude angle resolving unit comprises a vehicle body attitude multi-state matrix resolving function, a vehicle body attitude multi-state model resolving unit and a vehicle body attitude multi-state model resolving unit, wherein the vehicle body attitude multi-state matrix resolving function is used for obtaining a current vehicle running attitude angle; The body posture multi-state matrix solving function is shown as follows, kc=kc(κ1,κ2,κ3), Wherein, kappa 1 is a longitudinal attitude angle, kappa 2 is a transverse attitude angle, kappa 3 is a jump attitude angle, and kc is a matrix state of vehicle running attitude angles; The matrix state design attitude angle threshold value of the vehicle running attitude angle distinguishes the weight coefficient gamma to obtain the attitude angle evaluation factor lambda of the current vehicle running, λ=γ*kc, Wherein kc is a matrix state of a vehicle running attitude angle, and gamma is an attitude angle threshold distinguishing weight coefficient; The steering power-assisted mode switching control unit comprises a driving gesture safety mode, a driving gesture comfort mode and a driving gesture movement mode, wherein the driving gesture safety mode, the driving gesture comfort mode and the driving gesture movement mode are used for evaluating that a current vehicle is in different modes according to different intervals of a gesture angle evaluation factor compared with the stability degree of the driving gesture of the current vehicle, the steering power-assisted correction control degree required by the different modes is different, the gesture conversion control factors corresponding to the different modes are different, the gesture conversion control factor χ adapting to the driving state of the current vehicle is obtained, Wherein, beta 0 is a vehicle body side deflection angle vector, sigma 0 is a vehicle body side inclination angle vector, phi 0 is a vehicle body swing angle vector, delta 0 is a vehicle body pitch angle vector, t 1 is a longitudinal attitude angle resolving coefficient, t 2 is a transverse attitude angle resolving coefficient, t 3 is a jump attit