Vibration suppression in full car active suspension system using fractional order sliding mode controller

Abstract

Vehicle active suspension systems (VASS) are designed to improve ride comfort and road handling capacity in the automotive industry. This paper investigates the problem of vibration suppression in full car model (FCM) with active suspension system (ASS) whose aim is to reduce the effect of the vibrations generated by road irregularities on the human body. The mathematical model is developed for seven degrees of freedom (DOF) FCM. The main objective is to control vibration of FCM for various road disturbances such as bump and random road disturbance using a fractional order sliding mode controller (FOSMC) and sliding mode controller (SMC). The effectiveness of the controllers are validated using MATLAB/Simulink software in terms of root mean square (RMS) values of body acceleration (BA), pitch acceleration (PA) and roll acceleration (RA). Further the power spectrum density (PSD) of BA is considered to show the human sensitivity range. The simulation results are indicated that FOSMC shows superior performance at adapting bump and random road disturbances compared to SMC and passive suspension system (PSS).