Experimental Comparison of Passive, Semi-Active On/Off, and Semi-Active Continuous Suspensions

Abstract

A suspension control system for a suspension support ing a mass body on a support base via a parallel combi nation of a shock absorber having a variable damping coefficient and a spring. The control system cyclically measures absolute velocity (Z) of the mass body along a moving path of expansion and contraction of the shock absorber, relative velocity (Y) of the mass body in refer ence to the support base along the moving path, and acceleration (Z) of the mass body along the moving path. A control unit of the control system controls the damping coefficient according to a ratio (Z/Y) of the absolute velocity to the relative velocity with cyclic readjustment thereof so that at least either the damping coefficient is greater relative to the ratio when the ac celeration is rich in low frequency components or a frequency of the cyclic readjustment of the damping coefficient is lower when the acceleration is rich in high frequency components.

Modeling and control of magnetorheological dampers for seismic response reduction

“…The approach proposed here is to append a force feedback loop [25] to induce the MR damper to produce approximately a desired control force . A linear optimal controller is then designed that provides the desired control force based on the measured responses , and the measured force , i.e., (11) where { } is the Laplace transform.…”

Development and Testing of Hybrid Fuzzy Logic Controller for Car Suspension System Using Magneto-Rheological Damper

“…The damping coefficient of MR damper is b1, which is a variable with changing magnetic field depending on the flow of current through the damper coil. The Bouc-Wen model can be used to develop a semi-active control model for the magneto-rheological damper attached to the quarter car semi-active suspension system [12][13]. The model of the MR damper is assumed to be continuous in all the ranges and is numerically stable.…”

Development of a systematic and practical methodology for the design of vehicles semi-active suspension control system

“…Extensive theoretical and experimental studies of the performances of different types of semi-active Skyhook(-Groundhook) controllers can be found in the literature [3][4][5][6][7][8][9]. Nevertheless, the controller upper and lower gains; that is c max and c min are usually determined by trial-and-error, and there is no systematic method to adjust them.…”