Braking characterization of a multi-arc cylindrical magnetorheological fluid brake

To enhance the braking torque, this study proposes a multi-arc cylindrical magnetorheological fluid brake. Firstly, the structure and operational principle of the multi-arc cylindrical magnetorheological fluid brake is described in detail. Through finite element magnetic field analysis, the influence of arc radius variations and excitation current levels on flux density distribution are investigated. It is found that a larger arc radius in the multi-arc working gap leads to a lower average magnetic field strength. Then, a theoretical model is subsequently established to calculate braking torque within the working gap of a multi-arc magnetorheological fluid brake. The comparative evaluation of braking torque between the multi-arc configuration and conventional cylindrical counterparts demonstrate more than 42.20% torque enhancement under equivalent magnetic flux density conditions. To validate the theoretical predictions, a dedicated test platform was developed, with experimental measurements showing less than 5% deviation from theoretical data at magnetic saturation. These findings establish fundamental guidelines for optimizing magnetorheological brake geometries and provide actionable insights for industrial applications requiring high-torque compact braking solutions.