A Semi-Active, High-Torque, Magnetorheological Fluid Limited Slip Differential Clutch

The design, development, and performance characterization of a magnetorheological (MR) fluid clutch for automotive limited slip differential (LSD) applications is presented in this study. The controllability of MR fluids provides an adjustable torque transmission and slippage for the LSD application. Three-dimensional electromagnetic finite element analysis (FEA) is performed to optimize the magnetic circuit and clutch design. Based on the results obtained from the FEA, the theoretical torque transfer capacity of the clutch is predicted utilizing Bingham-Plastic constitutive model. The clutch is characterized at different velocities and electromagnet electric input currents. Both the torque transfer capacity and the response time of the clutch were examined. It was demonstrated that the proposed MR fluid LSD clutch is capable of transferring controllable high torques with a fast response time.