Analysis of Simplifications Applied in Vibration Damping Modelling for a Passive Car Shock Absorber

Abstract

The paper presents results of research on hydraulic automotive shock absorbers. The considerations provided in the paper indicate certain flaws and simplifications resulting from the fact that damping characteristics are assumed as the function of input velocity only, which is the case of simulation studies. An important aspect taken into account when determining parameters of damping performed by car shock absorbers at a testing station is the permissible range of characteristics of a shock absorber of the same type. The aim of this study was to determine the damping characteristics entailing the stroke value. The stroke and rotary velocities were selected in a manner enabling that, for different combinations, the same maximum linear velocity can be obtained. Thus the influence of excitation parameters, such as the stroke value, on force versus displacement and force versus velocity diagrams was determined. The 3D characteristics presented as the damping surface in the stoke and the linear velocity function were determined. An analysis of the results addressed in the paper highlights the impact of such factors on the profile of closed loop graphs of damping forces and point-type damping characteristics.

Hybrid modeling and verification of disk-stacked shock absorber valve

“…are undetermined coefficients, see Li and Li. 10 Making v m = f rmax = 12qC r 1 =(Ed 3 ), then q=d 3 = v m E=12C r 1 ; by substituting it into equation (2), the equation for the valve deflection based on the hybrid method can be written as…”

“…1 The shock absorber is an important part in a car's suspension, and its damping force characteristic plays a very important role in the safety and the comfort of the vehicle. 2 The throttle valve is an important part in the shock absorber, and its bending deformation directly influences the damping force characteristic of the shock absorber, which affects the performance of the suspension, that is, the ride comfort and the handling stability of the vehicle. 3 Each valve is characterized by different orifices, located in series or in parallel, which can have constant or variable areas.…”

Modern suspension systems for automotive vehicles and their test methods

“…The development of methods is directed at obtaining additional diagnostic information (not only the vibration amplitude in the resonance), such as, for example, the phase angle and the unambiguous association of this information with the vehicle mass distribution (the ratio of sprung and unsprung masses) [6,[14][15][16][17][18][19][20][21].…”

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

“…The shock absorber is one of the most important parts of vehicle suspension system, which has an effect on ride characteristics. It is also used to control the transient behaviour of the sprung and unsprung masses of the vehicle [4,5]. It is one of the most complex part of the suspension system because of its non-linear and complex behaviour.…”

“…Blundell [29] modelled the rear suspension system by using Adams view and showed the effect of rubber bush compliance on vehicle suspension movement. By using quarter car model, several researchers have carried out investigations on vehicle performance analysis [5,[31][32][33][34] using hydraulic shock absorber or MR fluid damper [35]. The full car modelling and analysis [36][37][38][39][40][41][42][43] had been carried out by some of the researchers.…”