Experimental identification of non-hysteresis algebraic force model of automotive hydraulic damper

Abstract

A systematic methodology through grey box modelling is proposed for the nonlinear force characterisation of telescopic hydraulic dampers. The structure of force model is obtained through the theoretical analysis of damper operation based on principles of mechanics. A theory is developed to estimate the model parameters from experimental testing by using both sinusoidal and cyclic ramp excitation. The Coulomb friction and gas force components are obtained from quasi-static sinusoidal motion of damper and the components of velocity dependent damping force are obtained by using cyclic ramp excitation. The commercially available vehicle damper is used to demonstrate the proposed methodology for characterisation of damper force. The model parameters are obtained and the model is validated with experimental results to show its effectiveness. Being algebraic in nature and less parameters, it will be easy to implement in vehicle simulation.