A semi-active suspension control algorithm for vehicle comprehensive vertical dynamics performance

This paper presents a comprehensive investigation of automotive semi-active suspension control algorithms and compares their characteristics in terms of ride comfort and tire-road holding ability. Particular attention has been paid to the semi-active suspension systems fitted with a shock absorber of dual damping characteristics. Different mathematical models are presented to investigate the ride response considering both simplified and complex vehicle models. Numerical simulation has been carried out through the MATLAB/SIMULINK environment which aids the future development of controllable suspension systems to improve vehicle ride comfort. The results show a considerable improvement of the vehicle ride response using different schemes of semi-active suspension system in particular the modified groundhook control algorithm.

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Wheelbase preview control of an active suspension with a disturbance-decoupled observer to improve vehicle ride comfort

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/0954407019886499 ◽

2019 ◽

Vol 234 (6) ◽

pp. 1725-1745

Author(s):

Baek-soon Kwon ◽

Daejun Kang ◽

Kyongsu Yi

Keyword(s):

Simulation Study ◽

Control Algorithm ◽

Ride Comfort ◽

Active Suspension ◽

The Body ◽

Vehicle Body ◽

Preview Control ◽

The Road ◽

Road Disturbance ◽

Suspension Control

This article deals with the design of a partial preview active suspension control algorithm for the improvement of vehicle ride comfort. Generally, while preview-controlled active suspension systems have even greater potential than feedback-controlled systems, their main challenge is obtaining preview information of the road profile ahead. A critical drawback of the “look-ahead” sensors is an increased risk of incorrect detection influenced by water, snow, and other soft obstacles on the road. In this work, a feasible wheelbase preview suspension control algorithm without information about the road elevation has been developed based on a novel 3-degree-of-freedom full-car dynamic model which incorporates only the vehicle body dynamics. The main advantage of the employed vehicle model is that the system disturbance input vector consists of vertical wheel accelerations that can be measured easily. The measured acceleration information of the front wheels is used for predictive control of the rear suspension to stabilize the body motion. The suspension state estimator has also been designed to completely remove the effect of unknown road disturbance on the state estimation error. The estimation performance of an observer is verified via a simulation study and field tests. The performance of the proposed suspension controller is evaluated on a frequency domain and time domain via a simulation study. It is shown that the vehicle ride comfort can be improved more by the proposed wheelbase preview control approach than by the feedback approach.

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Modeling and controlling a quarter-vehicle active suspension model

Journal of Physics Conference Series ◽

10.1088/1742-6596/2061/1/012138 ◽

2021 ◽

Vol 2061 (1) ◽

pp. 012138

Author(s):

Vu Hai Quan ◽

Nguyen Huy Truong ◽

Nguyen Trong Duc

Keyword(s):

Simulation Model ◽

Control Algorithm ◽

Active Suspension ◽

Passive Suspension ◽

The Road ◽

Control Signals ◽

Suspension Control ◽

Suspension Model ◽

Two Parameters ◽

Oscillation Damping

Abstract This paper presents an application of the LQR active suspension control algorithm for a vertical planar oscillation model developed for ¼ of a vehicle. The wheel smoothness and dynamics with the road surface are two parameters to provide control signals. A simulation model is developed here based on MATLAB software to compare and evaluate the LQR active suspension model with the passive suspension. The results obtained here shows an improvement for a number of parameters when utilizing the active suspension model including fluctuating amplitude; oscillation damping time; the displacement acceleration of the active suspension body.

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Adaptive Semi-Active Suspension and Cruise Control through LPV Technique

Applied Sciences ◽

10.3390/app11010290 ◽

2020 ◽

Vol 11 (1) ◽

pp. 290

Author(s):

Hakan Basargan ◽

András Mihály ◽

Péter Gáspár ◽

Olivier Sename

Keyword(s):

Control Systems ◽

Active Suspension ◽

Cruise Control ◽

Linear Parameter Varying ◽

Trade Off ◽

Look Ahead ◽

Vehicle Velocity ◽

Suspension Control ◽

Road Data ◽

Terrain Characteristics

Several studies exist on topics of semi-active suspension and vehicle cruise control systems in the literature, while many of them just consider actual road distortions and terrain characteristics, these systems are not adaptive and their subsystems designed separately. This study introduces a new method where the integration of look-ahead road data in the control of the adaptive semi-active suspension, where it is possible to the trade-off between comfort and stability orientation. This trade-off is designed by the decision layer, where the controller is modified based on prehistorical passive suspension simulations, vehicle velocity and road data, while the behavior of the controller can be modified by the use of a dedicated scheduling variable. The adaptive semi-active suspension control is designed by using Linear Parameter Varying (LPV) framework. In addition to this, it proposes designing the vehicle velocity for the cruise controller by considering energy efficiency and comfort together. TruckSim environment is used to validate the operation of the proposed integrated cruise and semi-active suspension control system.

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Comprehensive Analysis for Influence of Controllable Damper Time Delay on Semi-Active Suspension Control Strategies

Journal of Vibration and Acoustics ◽

10.1115/1.4035700 ◽

2017 ◽

Vol 139 (3) ◽

Cited By ~ 49

Author(s):

Yechen Qin ◽

Feng Zhao ◽

Zhenfeng Wang ◽

Liang Gu ◽

Mingming Dong

Keyword(s):

Time Delay ◽

Dynamic Characteristics ◽

Ride Comfort ◽

Hybrid Control ◽

Sliding Mode ◽

Control Strategies ◽

Active Suspension ◽

Test System ◽

Suspension Control ◽

Simulation Results

This paper presents a comprehensive comparison and analysis for the effect of time delay on the five most representative semi-active suspension control strategies, and refers to four unsolved problems related to semi-active suspension performance and delay mechanism that existed. Dynamic characteristics of a commercially available continuous damping control (CDC) damper were first studied, and a material test system (MTS) load frame was used to depict the velocity-force map for a CDC damper. Both inverse and boundary models were developed to determine dynamic characteristics of the damper. In addition, in order for an improper damper delay of the form t+τ to be corrected, a delay mechanism of controllable damper was discussed in detail. Numerical simulation for five control strategies, i.e., modified skyhook control SC, hybrid control (HC), COC, model reference sliding mode control (MRSMC), and integrated error neuro control (IENC), with three different time delays: 5 ms, 10 ms, and 15 ms was performed. Simulation results displayed that by changing control weights/variables, performance of all five control strategies varied from being ride comfort oriented to being road handling oriented. Furthermore, increase in delay time resulted in deterioration of both ride comfort and road handling. Specifically, ride comfort was affected more than road handling. The answers to all four questions were finally provided according to simulation results.

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Dynamic monitoring feedback iteration control for damping-adjustable semi-active suspension systems

Journal of Intelligent & Fuzzy Systems ◽

10.3233/jifs-189719 ◽

2021 ◽

pp. 1-9

Author(s):

Chongchong Li ◽

Jiangyong Xiong ◽

Tingshan Liu ◽

Ziang Zhang

Keyword(s):

Root Mean Square ◽

Working Conditions ◽

Control Algorithm ◽

Active Suspension ◽

Dynamic Monitoring ◽

Iteration Algorithm ◽

Mean Square ◽

Control Effect ◽

Analytic Hierarchy ◽

Vehicle Simulation

In order to further improve vehicle ride performance, a dynamic monitoring feedback iteration control algorithm is proposed by combining the features of a variable-damping semi-active suspension system and applying them to the system. A seven-degree-of-freedom finished vehicle simulation model is built based on MATLAB/Simulink. The root-mean-square values of the acceleration of the sprung mass, the dynamic travel of the suspension and the dynamic tire load are taken as evaluation indicators of vehicle ride performance. An analytic hierarchy process (AHP) is used to determine the weighting coefficients of the evaluation indicators, and a genetic algorithm is utilized to determine the optimal damping of the suspension under various typical working conditions. Suspension damping is controlled with a dynamic monitoring feedback iteration algorithm. The correction coefficients of the control algorithm are determined according to the deviation between the obtained damping and the optimized damping so that the control parameters will agree with the optimal result under typical working conditions, and the control effect under other working conditions is verified. The simulation results indicate that the proposed dynamic monitoring feedback iteration control algorithm can effectively reduce the root-mean-square value of the acceleration of the sprung mass by 10.56% and the root-mean-square value of the acceleration of the dynamic travel of the suspension by 11.98% under mixed working conditions, thus improving vehicle ride performance. The study in this paper provides a new attempt for damping control of semi-active suspension and lays a theoretical foundation for its application in engineering.

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Comparative simulation study on two estimation methods and two control strategies for semi-active suspension

Advances in Mechanical Engineering ◽

10.1177/16878140211007323 ◽

2021 ◽

Vol 13 (4) ◽

pp. 168781402110073

Author(s):

Wang Xin ◽

Gu Liang ◽

Dong Mingming ◽

Li Xiaolei

Keyword(s):

Sliding Mode Control ◽

Control Algorithm ◽

Sliding Mode ◽

Structural Characteristics ◽

Active Suspension ◽

Road Surface ◽

Estimation Methods ◽

Vehicle Dynamic ◽

Mode Control ◽

Computational Overhead

With regard to the structural characteristics of the McPherson suspension system, when a vehicle is being driven on a rough road surface, the force direction of the suspension varies. This poses challenges to the vehicle’s driving safety and handling stability. Based on Lagrangian equations, this paper proposes a new nonlinear semi-vehicle suspension model and presents comparative studies, conducted through simulation, on the estimated accuracy and computational overhead of the small-computational-overhead extended Kalman filter (EKF) and unscented Kalman estimation (UKF) methods, and on the effectiveness of the skyhook sliding mode control (SHSMC) and nonlinear skyhook-sliding mode control (NSHSMC) semi-active suspension control methods. The response of the vehicle to the state estimation algorithm was evaluated through computer simulations using the Carsim vehicle dynamic software. The simulation results reveal that the vehicle dynamic states were satisfactorily estimated when the vehicle was driven on a rough road surface. Compared with the small-computational-overhead EKF algorithm, the estimated results of these variables based on the UKF algorithm have higher accuracy. However, the UKF algorithm requires longer computation time compared with the EKF algorithm. The SHSMC control algorithm achieved greater improvement for the vehicle’s drive handling stability in the 6–10-Hz vibration region compared with the NSHSMC control algorithm. In a high-frequency region over 10Hz, the semi-active suspension controlled by the SHSMC method had a more adverse effect on the driving comfort.

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