DEVELOPMENT OF A LAP-TIME SIMULATOR FOR A FSAE RACE CAR USING MULTI-BODY DYNAMIC SIMULATION APPROACH

There are many challenges in race car development process right from making of prototype to realize an actual car. The development cost is proportional to the number of prototypes used during the process. This brings in the necessity of a lap-time simulator that aid in data driven decision making during multiple lap configurations without an actual physical test of the vehicle. Development of lap-time simulator is a complex task. It requires a multi-body dynamic simulation approach. The simulator has to account for vehicle performance, handling and ride comfort. The vehicle performance is not only influenced by ideal power characteristics provided by the power unit and transmission system, but depends on the role of tire to maximize the tractive/braking effort realized at the contact patch during complex tire road interaction. It is mainly influenced by location of center of gravity, dynamic longitudinal load transfer, and the aerodynamic and rolling resistances. The vehicle response for handling inputs such as steering and environmental inputs decides the vehicle directional control and stability of the vehicle, which is influenced by dynamic load transfer, and cornering slip stiffness of the tires. The roll, pitch and bounce motion decides the ride comfort level of the vehicle. The main aim of this paper is to present a lap-time simulator developed for vehicle performance and handling characteristics for linear operational range. The modeling of the simulator has been divided into 3 segments .The first segment corresponds to tire modeling. The second segment has two sub-segments concerned with developing the vehicle modeling which includes the vehicle modeling for longitudinal dynamics as well as lateral dynamics [1]. The final segment concerned with creating an algorithm for tracking the vehicle on a predefined map and executing the prescribed motions. Hence, it is understood that there are many advantages of a lap-time simulator, importantly, it reduces number of prototypes and hence reduces the vehicle development cost.