Observing the Durability Effects of a Formula Student Electric Car using Acceleration and Strain Signals

Abstract

This paper presents the durability analysis of suspension system from an electric Formula Student race car using strain and acceleration signals. To have outstanding performance in a competition, the Formula Student car was required to have light weight but safe design. To evaluate the suspension design of the vehicle, strain and acceleration signals were collected under a vehicle double lane change event according to the ISO 3888 testing procedure. Strain signals were measured on the wheel carrier and lower control arm of the Formula Student car. Meanwhile, tri-axis accelerations were measured on the wheel and chassis of the vehicle during the testing. In addition, the wheel displacement relative to vehicle chassis was measured using laser sensors. The fatigue life of the lower arm and wheel carrier were predicted using the measured strain signals. Due to limited instrument, a quarter car model was simulated using wheel displacement signals to obtain spring force signals for fatigue estimation. The simulation model was validated using the measured chassis acceleration signal. Ride and whole-body vibration of the vehicle were also assessed using the measured acceleration signals. Through this analysis, the durability effects of the Formula Student car suspension system were identified. The Formula Student car suspension design could be improved through understanding the vibration behaviour.