Development, optimization, and control of a novel magnetorheological brake with no zero-field viscous torque for automotive applications

The significant energy loss due to viscous torque generation in the absence of the applied magnetic field is the main obstacle in the practical realization of magnetorheological brake in the automotive applications. In this study, a novel magnetorheological brake design having no viscous torque generation in the absence of applied magnetic field has been proposed. The Herschel-Bulkley constitutive model is employed to develop the mathematical equations governing the system's braking torque. Magnetic circuit analysis of the proposed magnetorheological brake has been conducted to predict the magnetic field intensity in the magnetorheological fluid gaps. A multidisciplinary optimization problem has been formulated to identify the optimal brake parameters to maximize the braking toque while minimizing response time and weight of the magnetorheological brake under different constraints. Genetic algorithm combined with sequential quadratic programming algorithm has been utilized to find the true global optimal solution. The optimal design of the proposed magnetorheological brake provides a maximum braking torque of 1802 N m, a response time of 150 ms, and an overall weight just under 37 kg. Finally, braking performance of the proposed magnetorheological brake has been investigated in a quarter vehicle model where a proportional-integral-derivative controller has been integrated with the proposed magnetorheological brake to improve vehicle's slipping on different road conditions.