Design, Analysis, and Development of a Custom Helical Limited Slip Differential for Formula Student Applications

This study focuses on the design, analysis, and development of a custom helical limited-slip differential (LSD) for a Formula Student race car. In a standard open differential, torque is not distributed equally during high-torque or low-traction conditions, which leads to wheel slip and affects the vehicle's performance and control. To overcome this, the proposed design uses helical gears to automatically transfer more torque to the wheel with a better grip without using friction plates or viscous systems. The overall process includes the selection of the gear mechanism, calculation of the torque bias ratio, CAD modelling with three design iterations, selection of materials (7075-T6 aluminum for the casing and EN19/AISI 4140 steel for gears), and structural analysis using SolidWorks FEA. The results show that all components are within safe stress limits, where the casing shows a maximum von Mises stress of 376 MPa compared to a yield strength of 505 MPa (FOS = 3.7), and the pinion and side gears have factors of safety of 4.6 and 11, respectively. The calculated torque bias ratio of 2.09:1 confirms that the differential can effectively improve traction and handling under racing conditions.