MODELING AND SIMULATION OF VEHICLE BEHAVIOR FOR DESIGN AND TUNING OF ELECTRONIC DIFFERENTIAL FOR FORMULA STUDENT VEHICLE

摘要

A racing vehicle requires to be designed for optimum performance, stability and maneuverability considering all situations like straight line acceleration and high speed cornering. The car is driven close to its tractive limits and a control system becomes inevitable to manifest utmost performance of the car. In this paper, the focus is on design of an electronic differential for a rear wheel driven Formula Student Electric vehicle, with each rear wheel driven by separate motors. The electronic differential (e-diff) is aimed at both straights and corners, which is fulfilled by considering objective parameters, which assist in cornering by improving yaw rate and straights by improving traction. However, in this paper we shall focus on cornering only. The paper looks at various possible control strategies for obtaining desired values of certain parameters and describes in detail implementation of a yaw rate controlled system. A vehicle model is created on MATLAB/Simulink platform to look at changes in vehicle behavior in response to various control strategies. The model consists of vehicle dynamics and driver models developed by the authors. The coupled model simulates the vehicle performance on any given track and provides the variation of required parameters. Iterations are done and the results are used to tune the controller parameters to optimize performance on tight turns and overall lap times at the endurance event at the Formula Student competition.