Vehicle Steering Stability Research Articles

Steer-by-wire control algorithm using a dual-layer closed-loop model

Steer-by-wire (SBW) is a crucial chassis electronic control system. Accurate and rapid wheel angle control is key to enhancing system performance. This paper first establishes a dynamics model of the steering actuator. Then, a co-simulation vehicle model with CarSim and Simulink is built, and the feasibility of the SBW model is experimentally verified. Based on this, a front wheel angle compensation difference tracking strategy is proposed using the front wheel steering angle control method. This strategy compensates for the difference between the actual and ideal front wheel steering angles to achieve the desired front wheel angle progressively. A dual-layer controller is designed in the Simulink module and integrated with the CarSim module to achieve closed-loop feedback control of the front wheel angle. The upper layer controller employs a fuzzy PID control method to execute the front wheel angle compensation strategy, enabling two corrections of the front wheel angle and yaw rate. The lower layer controller corrects wheel angle information to improve control effects. Simulation results under double lane change and single lane change conditions show that the fuzzy PID controller with front wheel angle compensation significantly enhances vehicle steering stability. Notably, at high speeds, the peak yaw rate is lower, convergence speed is faster, and response time is shorter.

Research on the Vehicle Steering and Braking Stability Region

Solving the stability region in the plane motion of vehicles has become a hot research topic in vehicle handling stability under extreme conditions, but there is still a lack of research on the stability region under steering and braking conditions. In this paper, a five-degree-of-freedom (5DOF) nonlinear dynamic model of a vehicle with braking torque introduced is established, and the model is transformed into an equivalent system by using the D’Alembert principle. Then, the equilibrium points of the equivalent system are solved by using an improved hybrid algorithm combining the genetic algorithm (GA) and sequential quadratic programming (SQP) method. According to the bifurcation characteristics of the equilibrium points, the boundary of the stability region at the given initial longitudinal velocity is determined, and the three-dimensional stability region is fitted. Finally, the stability region of the equivalent system and the original system are analyzed by the energy dissipation method, and the stability region determined by the equilibrium point bifurcation method is verified by simulation. The results show that as the braking torque increases, the number of equilibrium points increase to three from one, the equilibrium bifurcation method proposed in this paper can effectively solve the stability region of the equivalent system, and the solution results are consistent with the original system stability region. When the limited braking torque is 500 N·m and the initial longitudinal velocity increases from 30 m/s to 50 m/s, the absolute value of the front wheel steering angle at the boundary point changes from less than 0.02 rad to more than 0.02 rad.

Integrated Adaptive Steering Stability Control for Ground Vehicle with Actuator Saturations

During a steering manoeuvre in a ground vehicle, both yaw motion and roll motion can occur simultaneously, and their dynamics can be coupled, as the roll motion is generalized directly from the tires’ lateral force under steering. Hence, it is of significance to analyze them as an integrated plant in the vehicle steering stability control problem. Furthermore, the actuator saturation of yaw control cannot be neglected, as vehicles often steer at a high velocity or on low-friction roads. In this paper, an integrated steering dynamics model is established considering the coupling between the roll motion and lateral motion, then a novel nonlinear adaptive controller is proposed to stabilize the steering motion considering the actuator saturation of yaw motion control. Simulation results indicate that the designed integrated controller is effective in improving the performance of both the yaw rate tracking error and ride comfort taking into account vehicle parameter uncertainties and actuator saturation; the steering stability of ground vehicles can consequently be guaranteed.

Research on Steering Control of Modern Trackless Train with Multi-Articulated Distributed Drive

Modern trackless train has the characteristics of long body and many articulated modules, and the steering control is extremely difficult. This paper first established its Adams dynamic model, and then designed a fuzzy PID controller to generate the yaw moment and rear wheel angle. So that the vehicle can track the trajectory of the first axle when turning. Finally, the control model was established in Matlab and simulated jointly with Adams model. The simulation experiments under step input and sinusoidal input were carried out. The results show that the active steering control strategy based on the combination of direct yaw moment and rear wheel angle can meet the requirements of vehicle steering stability and trajectory following.

Continuous Steering Stability Control Based on an Energy-Saving Torque Distribution Algorithm for a Four in-Wheel-Motor Independent-Drive Electric Vehicle

In this paper, a continuous steering stability controller based on an energy-saving torque distribution algorithm is proposed for a four in-wheel-motor independent-drive electric vehicle (4MIDEV) to improve the energy consumption efficiency while maintaining the stability in steering maneuvers. The controller is designed as a hierarchical structure, including the reference model level, the upper-level controller, and the lower-level controller. The upper-level controller adopts the direct yaw moment control (DYC), which is designed to work continuously during the steering maneuver to better ensure steering stability in extreme situations, rather than working only after the vehicle is judged to be unstable. An adaptive two-hierarchy energy-saving torque distribution algorithm is developed in the lower-level controller with the friction ellipse constraint as a basis for judging whether the algorithm needs to be switched, so as to achieve a more stable and energy-efficient steering operation. The proposed stability controller was validated in a co-simulation of CarSim and Matlab/Simulink. The simulation results under different steering maneuvers indicate that the proposed controller, compared with the conventional servo controller and the ordinary continuous controller, can reduce energy consumption up to 23.68% and improve the vehicle steering stability.

Simulation of Cornering with Steer Release and Optimization of Vehicle Steering Stability

According to the principle of multi-body dynamics, using ADAMS module of ADAMS/CAR to form a complete vehicle model, and by using INSIGHT module used to design suspension hard point, the simulation analysis was carried out . Controllability and stability of the vehicle is to make evaluation and analysis by the experiments cornering with steer release. Ordinal optimization of before and after the optimization model , the results were analyzed, it demonstrated that optimized score significantly higher than before optimization.

Chaos vibration of pinion and rack steering trapezoidal mechanism containing two clearances

The multi-clearances of breaking type steering trapezoidal mechanism joints influences vehicle steering stability. Hence, to ascertain the influence of clearance value on steering stability, this paper takes the steering mechanism of a certain vehicle type as a prototype that can be simplified into a planar six-bar linkage, then establishes the system dynamic differential equations after considering the two clearances of tie rods and the steering knuckle arms. The influence of the clearance parameters on the movement stability of the steering mechanism is studied using a numerical computation method. Results show that when the two clearances are equal, the planar movement of the tie rods changes from period-doubling to chaos as the clearances increase. When the two clearances are 0.25mm and 1.5mm respectively, the planar movements of the two side tie rods come into chaos, causing the steering stability to deteriorate. Moreover, with the increase of clearances, turning moment fluctuates more intensively and the peak value increases.

Application Research on Vehicle Steering Stability Based on ADAMS/CAR

A multi-body simulation approximate model of a vehicle using ADAMS/CAR software is established. According to the experimental evaluation criteria and methods related to vehicle steering stability of the country, conducting the steering transient test, the steering back to positive Experimental as well as the Sine - Swept steering simulation. Exploring a parametric design method for vehicle handling stability ADAMS / CAR to analyze

Study of Vehicle Handling Stability Based on MATLAB

In this paper, the sideslip angle and yaw velocity as parameters are presented to describing the motion state of the motion state of the vehicle, in which two DOF(degree of freedom) vehicle model is used as the reference model. And car speed is considered as the system step input to building a three DOF vehicle model based on H.B. Pacejka’s tire model. Meanwhile, the sideslip angle and the yaw velocity are taken as the system outputs. And achieve simulated analysis of vehicle handing stability by using Simulink. The results show that the three DOF vehicle model is more accurate in description of transport condition, which provides reference for the study of the vehicle steering stability.

Research on the Influence Factors for Bus Based on Nonlinear Model

Improved 5-DOF vehicle which contains nonlinear steering and tire models was established to solve the deficiency of conventional dynamic linear models to analyze coupling characteristics. Based on GPS technology, a developed vehicle handing and steering stability detecting system comprised by Steering Force and Angle Tester, GPS, Gyroscope and high precision Data Collector was introduced. According to Matlab/Simulink platform and vehicle test, the dynamic model was verified. Then some influence factors on bus handing and steering stability such as structure parameters, suspension parameters and tire parameters were analyzed. The results show that the longitudinal position of gravity and the vertical distance of gravity and roll axis have a good effect on vehicle yaw and roll responses. Spring roll stiffness is important parameter for vehicle roll. The pneumatic trail is closely related on steering reversibility and comfort. These researches have direct reference value for bus design.

Research on the Affection of Vehicle Lateral Stability Related to the Improved ABS

When automobile is braking in a turn, the left and right wheel load changes, often leads to excessive loss of vehicle steering stability. The process of steering is often accompanied with braking, we can improve the control strategy of anti-lock braking system which widely used in vehicles to maintain the steering-braking lateral stability.

Vehicle Steering Stability Simulation Based on G-Vectoring Control

A new kind of control method named "G-Vectoring control" is used in vehicle steering stability control, which uses the lateral acceleration to control the longitudinal acceleration, and improves the steering stability by redistributing the driving force. The motor and its control system as well as the vehicle system control are modeled by Matlab, the vehicle dynamics model is designed by adams. After the co-simulation of snakelike tests, the results shows that the sideslip angle is well controlled by G-Vectoring control.

The Effects of Tire Nonlinearity on Vehicle Steering Stability at High Speed

The steering stability of a vehicle at high speed is the urgent key problem to be solved of automobile independent development. And it is also the premise and one of the necessary conditions of vehicle safety. Considering of the effects of tire nonlinearity, a 4-DOF dynamics model for a vehicle is established. The yaw rate responses, side slip angle, carriage roll angle and front wheel steering angle with different vehicle speeds are calculated. The calculated values are then compared with the values without considering of the effects of tire nonlinearity. The simulations results show that the vehicle responses can be reflected accurately by using nonlinear tire model. With the bigger vehicle speed, the effects of tire nonlinearity on vehicle high-speed steering stability become more obvious.

Modeling and Analysis of the Proportional Control Four-Wheel Steering Vehicle Handling and Stability

Four-wheel steering (4ws) refers to the meaning of besides usually turn the front wheels of the vehicle, plus the corresponding rear wheel steering. Its main purpose is to increase the vehicle steering stability at high speed or in lateral force under the action , improve the vehicle steering portability at low speed and turning radius at high speed.A 4ws vehicle dynamic model with two-degree of freedom[1,2] was established, and presents the corresponding dynamic equation. Using the theory of vehicle handling dynamics,according to the 4ws vehicle dynamic equation,the transient response of 4ws vehicle steering are detailed analyzed.Compared with 2ws steering, illustrates the manipulation of 4ws vehicle has strong handling stability.

Modeling and Simulation Based on AMESim and Simulink Electric Hydraulic Power Steering System

This article using AMESim and Simulink software co-simulation technology and appropriate software to establish the simulation model of the key components of the steering system, it is found the factor which affect vehicle handling and stability of steering system in the structure by analyzing the impact of various parameters on the car steering system. It is to verify the feasibility of the model and study how steering system of all kinds of main factor to influence the vehicle steering stability through Simulink and AMESim software co-simulation results cf vehicle steering stability GB experiments.

Study on Mechanism of Active Front Steering Based on Harmonic Drive

The steering ratio of vehicle can be changed by attaching a angle, Changing the steering gear ratio can improve the safety in high-speed and comfort in low-speed and the vehicle steering stability. The paper introduces an active front steering system (AFS) based on harmonic drive, the composition and working principle of the system are analyzed, and the kinematic analysis of the system is researched, finally, the self-control mechanism and integrated control mechanism with other stability system are studied.

The Research on 4WS Vehicle Steering Stability by Modeling and Simulation

In order to improve vehicle steering stability, the influence of tire loads and steering system to the vehicle stability is taken into account in this paper, and the 4WS vehicle model is established and modeling and simulation research is carried through with the Matalab/simulink. The results point out the differences and characters of vehicle control mode in low speed and high speed. This model provides a method for 4WS vehicle design, improvement and optimization, and also provides reference for 4WS theory research and test check.

Dynamic analysis of steering system of the articulated vehicle in the heeled status

In order to research the dynamic characteristic when the articulated vehicle accelerates, brakes and steers, it is necessary to analyze the force of the front and the rear car body and establish the steering dynamic mathematical model and simulation model when the articulated vehicle is in the heeled status. Taking the FW - 6 underground service car as an example, the results of the numerical simulation when the initial velocity of the vehicles is 12m/s, the heeled angle of rear car body is 0° and the heeled angle of front car body is 8° show that the dynamic responses of the steering acceleration, steering angle and steering speed are strong, at the same time, the vehicle steering stability is seriously impacted.

The performance of a vehicle with four-wheel steering control in crosswind

A nonlinear 5 degrees of freedom (DOF) system is used to model the dynamics of a four-wheel steering control vehicle. In the model the yawing and roll motions of the sprung mass of the vehicle are considered and the nonlinear differential equations of motion are derived. In addition, the crosswind model and the driver model are established in this paper. They are used to investigate both the conventional front-wheel steering (FWS) and the four-wheel steering (4WS) vehicle during a crosswind disturbance. Two different 4WS control laws are used. The first is an open loop control law (OL4) in which the rear wheel steering angle is only determined by the front wheel steering angle. The second is a closed loop law (CL4) in which the rear wheel angle is determined by both the front wheel steering angle and the yawing angle of the sprung mass of the vehicle. Simulation results indicate that the CL4 system significantly improves the vehicle steering stability in response to a crosswind disturbance.