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This paper presents a mathematical model of an electric driveline consisting of one battery pack, two independent Permanent Magnet DC (PMDC) motors and motor-controllers and two fixed-ratio planetary gearboxes, all located inside the rear frame of the vehicle. The proposed analysis has been performed with the objective of: (i) Determination of acceleration run time for a straight patch of 75 meters; (ii) Determination of lap times and energy consumption for endurance track of 23 laps. A model of a PMDC motor and motor controller has been developed based on response analysis by conducting experiments on a jig setup. The motor controllers are compared for two control modes- Speed mode and Torque mode. A simplified race car model for longitudinal vehicle dynamics is derived from forces acting on the car including the effect of losses due to drag forces, rolling resistance, transmission inefficiency and inertial losses due to rotary elements.

This paper involves the study of implementation of an active electronic differential using torque vectoring in an electric rear wheel drive vehicle. The proposed system works in a closed loop taking feedback in real time from sensors which provides inputs for steering angle, throttle position, angular velocity of wheels, yaw rate, yaw acceleration, longitudinal acceleration and lateral acceleration. The objective of this system is to i) increase the stability and the vehicle response to the driver while turning, and ii) use the traction available on the driven wheels more efficiently. The system involves applying a torque difference between the rear driven tires to create a moment about the centre of mass that causes yaw acceleration and aids in turning the car by increasing yaw rate. The effect of drag forces and the lateral forces on the tires have been included. An optimized desired moment is calculated which is applied via torque difference while turning.

This paper presents the method of designing an optimized light weight, cost effective planetary gearbox for a Formula Student vehicle. The gearbox has a high speed functioning capability, in addition to the compact size and light weight. The iterative optimization procedure used provides a technique for selecting the best possible configuration of the gearbox. Conventional gearboxes used for this purpose are generally two step reduction gearboxes, which are bulkier in terms of weight and volume. Also, a review of the existing market reveals that the planetary gearboxes manufactured in India are not capable of handling high speeds, thus rendering them futile for racing applications. The target reduction ratio for the gearbox is a fixed parameter. The method involves design and optimization of the gear-train with the calculated ratio.