Geometric optimization of controllable magnetorheological shock absorber for commercial passenger vehicle

Abstract

This paper presents optimal design of a controllable magnetorheological (MR) shock absorber for a passenger vehicle and shows several advantages of the optimized MR shock absorber on vibration control performance. In order to achieve this goal, a cylindrical MR shock absorber, which satisfies design specifications for a mid-sized commercial passenger vehicle, is designed using an optimization methodology. The optimization problem is to find optimal geometric dimensions of the magnetic circuit for the MR shock absorber in order to maximize damping force. The first order optimization method using commercial finite element method (FEM) software is adopted for the constrained optimization algorithm. After manufacturing the MR shock absorber with optimally obtained design parameters, its field-dependent characteristics are experimentally evaluated. The effect of the optimized MR shock absorber on suspension control is investigated using a quarter-vehicle system. Control performances such as vertical acceleration and power consumption are evaluated and compared between the initial and optimal shock absorbers.