Analysis of a quarter car suspension system based on nonlinear shock absorber damping models

Abstract

Shock absorber is a critical element of vehicle suspension system with nonlinear characteristics. In the present work, performance of vehicle characteristics was analysed by quarter car model to study the effect of shock absorber, on the basis of linear and nonlinear damping characteristics. In addition to linear and piecewise linear, polynomial damping characteristics were considered to address the nonlinear aspect of damping characteristics. The linear and nonlinear properties of the shock absorber were incorporated in a two degree of freedom quarter car suspension system. The modelling and simulation is carried out in Adams view environment and Matlab/Simulink. A bump road profile was used to excite the quarter car suspension models. The polynomial shock absorber model was validated using experimental data taken from established literature. Simulation was undertaken to study the dynamic performance in terms of sprung mass acceleration, body displacement, suspension deflection and unsprung mass acceleration. Experimental hysteresis characteristics data, taken from established literature, were also modelled in Adams view environment and the simulated results were used for validation purpose. The suspension system response incorporating shock absorber represented by nonlinear model, hysteresis model and piece wise linear model were provided in the result section for comparison. It was observed from quantitative comparisons that the RMS values for body acceleration and body displacement of the polynomial model matched fairly well with the results of experimental hysteresis response. It was concluded that in order to study the dynamic characteristics of the vehicle accurately, nonlinear behaviour of the damper is required to be captured properly. Therefore, the proposed polynomial shock absorber model can be a better option for vehicle dynamic analysis as compared to the complex hysteresis model.

Modeling and Simulation of Semiactive and Active Suspension System using Quarter Car Model

“…The spring of the suspension system has stiffness k s , whereas c s is the constant suspension damping coefficient. The equations of motion for the passive suspension system are given by [10];…”

An adaptive approach for vehicle suspension system control in presence of uncertainty and unknown actuator time delay

“…Figure 1 shows the 1/4 vehicle model considered in this paper for designing of the active suspension control law. This model is deduced from very important features in detailed models of papers (Barethiye et al, 2017;Sun et al, 2014). The equations of motion for sprung mass and unsprung mass are:…”

Comparative Study of Different Vehicle Models with Respect to Their Dynamic Behavior

“…Depending on the focus of each study, various models have been used in order to simulate the dynamic behaviour of a vehicle by modelling the tires, the body and the suspension system. Simple models of one or two degrees of freedom (quarter car model [1][2][3]), can be found in the literature. Since the quarter car model does not take into account any rotational degrees of freedom, its usage is limited to fairly simple suspension design optimisation problems and preliminary results.…”