Analysis of a Smart Suspension System Based on Vibration Sensors in Small Vehicles

Abstract

This paper describes an applied–experimental study on smart suspension for small passenger cars, using micro-electromechanical systems (MEMS) accelerometers to provide real-time adaptive damping. The system combines the multi-axis vibration sensing with digital signal processing and semi-active MR dampers, for active control of ride comfort, road handling, and tire–road contact stability. A small hatchback platform was equipped with an in-house developed sensor actuator network and driven over specifically prepared road excitations, such as fine asphalt, speed bump or rough surface at velocities between 20 and 60 km/h at different loading conditions. Performance was assessed in terms of ISO 2631-1 ride comfort indices, damping ratios, suspension travel and dynamic tire load fluctuation. The proposed system has shown that RMS body acceleration is reduced by up to 33% while dynamic tire load variation is reduced by 30–40 %, compared with the conventional passive suspension. This paper also investigates the practical problems of sensor preciseness, processing latency and system integration on an automotive platform with limited resources. The insights gained here yield practical guidance for the implementation of smart suspensions on electrically powered and/or self-driving city vehicles, which must overcome stringent space, weight and energy efficiency design constraints.