Investigation of Four-wheel Steering Algorithms for a Formula SAE Car

An algorithm was developed for a speed-dependent four-wheel steering system for a Formula SAE car.

A linear bicycle model was implemented using the MATLAB and SIMULINK software packages. Various control laws were investigated for the rear steer angle with the objective of reducing the sideslip angle.

A full 3D model of the vehicle incorporating weight transfer and tire non-linearity was then developed using the DADS software. An algorithm developed using the linear model with the aim of reducing vehicle sideslip angle was implemented in the nonlinear model. It is shown that this algorithm can improve the dynamic performance for both high-speed and low-speed maneuvers.