A Comfort Oriented Control Strategy for Semi-Active Suspensions Based on Half Car Model

This paper is devoted to the design of a novel semi-active comfort-oriented control strategy based on the “half-car” modeling of the vehicle. The half car model is an effective description of the vertical behaviors in a vehicle like a motorcycle, since it is able to represent both the heave and pitch dynamics. A recent control strategy (the “Mix-1-Sensor”) have been proven to be the quasi-optimal control strategy when the system is described with a quarter car model and the comfort objective is the control goal. This paper presents an analysis of the performances of the Mix-1-Sensor implemented in a half car: this strategy is able to guarantee a quasi optimal performance in terms of heave dynamics but it is not able to manage the pitch dynamics efficiently. A pitch-oriented extension of this strategy is proposed in order to guarantee a better filtering of the pitch dynamics.

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Semi-Active Suspensions: An Optimal Control Strategy for a Quarter-Car Model

IFAC Proceedings Volumes ◽

10.1016/s1474-6670(17)30401-9 ◽

2004 ◽

Vol 37 (22) ◽

pp. 553-558 ◽

Cited By ~ 5

Author(s):

Sergio M. Savaresi ◽

Enrico Silani ◽

Sergio Bittanti

Keyword(s):

Optimal Control ◽

Control Strategy ◽

Optimal Control Strategy ◽

Active Suspensions ◽

Quarter Car Model ◽

Car Model ◽

Quarter Car

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On the Benefits of Semi-Active Suspensions with Inerters

Shock and Vibration ◽

10.1155/2012/640275 ◽

2012 ◽

Vol 19 (3) ◽

pp. 257-272 ◽

Cited By ~ 22

Author(s):

Xin-Jie Zhang ◽

Mehdi Ahmadian ◽

Kong-Hui Guo

Keyword(s):

High Performance ◽

Control Method ◽

Hybrid Control ◽

Active Suspension ◽

Vertical Acceleration ◽

Active Suspensions ◽

Quarter Car Model ◽

Suspension Systems ◽

Car Model ◽

Quarter Car

Inerters have become a hot topic in recent years especially in vehicle, train, building suspension systems, etc. Eight different layouts of suspensions were analyzed with a quarter-car model in this paper. Dimensionless root mean square (RMS) responses of the sprung mass vertical acceleration, the suspension travel, and the tire deflection are derived which were used to evaluate the performance of the quarter-car model. The behaviour of semi-active suspensions with inerters using Groundhook, Skyhook, and Hybrid control has been evaluated and compared to the performance of passive suspensions with inerters. Sensitivity analysis was applied to the development of a high performance semi-active suspension with an inerter. Numerical simulations indicate that a semi-active suspension with an inerter has much better performance than the passive suspension with an inerter, especially with the Hybrid control method, which has the best compromise between comfort and road holding quality.

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A method for constructing an optimal control strategy in a linear terminal problem

Journal of the Belarusian State University. Mathematics and Informatics ◽

10.33581/2520-6508-2021-2-38-50 ◽

2021 ◽

pp. 38-50

Author(s):

Dzmitry A. Kastsiukevich ◽

Natalia M. Dmitruk

Keyword(s):

Optimal Control ◽

Control Strategy ◽

Time Instant ◽

Open Loop ◽

Optimal Control Strategy ◽

Worst Case ◽

Terminal Set ◽

Linear Discrete System ◽

Control Goal ◽

Bounded Disturbances

This paper deals with an optimal control problem for a linear discrete system subject to unknown bounded disturbances, where the control goal is to steer the system with guarantees into a given terminal set while minimising the terminal cost function. We define an optimal control strategy which takes into account the state of the system at one future time instant and propose an efficient numerical method for its construction. The results of numerical experiments show an improvement in performance under the optimal control strategy in comparison to the optimal open-loop worst-case control while maintaining comparable computation times.

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Optimal Control Design of Active Suspension System Based on Quarter Car Model

JURNAL INFOTEL ◽

10.20895/infotel.v11i2.429 ◽

2019 ◽

Vol 11 (2) ◽

pp. 55

Author(s):

Nur Uddin

Keyword(s):

Optimal Control ◽

Ride Comfort ◽

Control Design ◽

Active Suspension ◽

Suspension System ◽

Passive Suspension ◽

Quarter Car Model ◽

Car Model ◽

Passive Suspension System ◽

Quarter Car

The optimal control design of the ground-vehicle active suspension system is presented. The active suspension system is to improve the vehicle ride comfort by isolating vibrations induced by the road profile and vehicle velocity. The vehicle suspension system is approached by a quarter car model. Dynamic equations of the system are derived by applying Newton’s second law. The control law of the active suspension system is designed using linear quadratic regulator (LQR) method. Performance evaluation is done by benchmarking the active suspension system to a passive suspension system. Both suspension systems are simulated in computer. The simulation results show that the active suspension system significantly improves the vehicle ride comfort of the passive suspension system by reducing 50.37% RMS of vertical displacement, 45.29% RMS of vertical velocity, and 1.77% RMS of vertical acceleration.

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Control of a Quarter-Car Model With Variable Damping

Volume 7A: 17th Biennial Conference on Mechanical Vibration and Noise ◽

10.1115/detc99/vib-8042 ◽

1999 ◽

Author(s):

G. Verros ◽

S. Natsiavas ◽

G. Stepan

Keyword(s):

Control Strategy ◽

Piecewise Linear ◽

Damping Coefficient ◽

Active System ◽

Quarter Car Model ◽

Car Model ◽

Shock Absorbers ◽

Car Suspension ◽

Quarter Car ◽

The Stability

Abstract Dynamics of a strongly nonlinear quarter-car model is investigated. The nonlinearity is due to a control strategy which selects the damping coefficient of the car suspension in a way that the resulting semi-active system approximates the performance of an active suspension system designed to produce sky-hook damping. According to this control strategy, the damping coefficient switches between two different positive values, leading to a piecewise linear dynamical model. For this model, the equation of motion is first presented in a general normalised form. Then, an appropriate methodology is applied for obtaining exact periodic motions for the case of forcing resulting from a road with harmonic profile. This methodology is based on employing the exact solution form within response intervals where the damping coefficients remain constant. The unknowns of the problem are then determined by imposing a set of periodicity and matching conditions. The stability analysis of the located motions is also performed by applying a method which is suitable for piecewise linear systems. Next, this analysis is applied and representative numerical results are obtained. Namely, response diagrams are presented, showing the effect of the important system parameters on the existence, amplitude and stability properties of various branches of periodic solutions. The results are also compared to those of the conventional suspension systems, including passive bilinear shock absorbers.

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