Design and evaluation of a novel magnetorheological brake with coils placed on the side housings

Abstract

In the design of a traditional magnetorheological brake (MRB), coils are often placed on the cylindrical housing of the brake. This results in many disadvantages such as a ‘bottle-neck’ problem of magnetic flux. Moreover, in this design a nonmagnetic bobbin is required, and difficulties in manufacturing and maintenance exist. In order to resolve this problem, in this study a new configuration of MRB with coils placed on the side housings of the brake is proposed, optimally designed and experimentally evaluated. After describing an introduction of the proposed configuration, braking torque of the MRB is analyzed based on the Bingham-plastic rheological model of magnetorheological fluid (MRF). The optimization of the proposed and conventional MRBs is then performed considering maximum braking torque and mass of the brakes. In the optimization, both rectangular and polygonal shapes of the brake housing are considered. Based on the optimal results, a comparison of the performance characteristics of the proposed MRB and the conventional one is undertaken. In addition, an experimental test of the MRBs is conducted, and the results are presented in order to validate the performance characteristics of the proposed MRB.