Torque Characterization of T-shaped Magnetorheological Brake Featuring Serpentine Magnetic Flux

Abstract

Recently, T-shaped Magnetorheological Brake (MRB) usually utilize more than one wire coil electromagnetic to maximize magnetic flux reaching all Magnetorheological Fluid (MRF) gaps. This research was focused on the usage of a single wire coil on MRB with uniformly magnetic flux distribution. To achieve the goal, the serpentine magnetic flux profile was adopted to maximize all MRF gaps that only use a single coil. Firstly, the magnetic circuit which implementing serpentine magnetic flux was design in a two-dimensional model. It was then followed by magnetostatic simulation using Finite Element Method Magnetics (FEMM) to determine the amount of magnetic flux density. The data were then employed to calculate the braking torque. After having the final dimension and completing the workshop drawing, an MRB prototype was fabricated. Thus, the prototype was characterized using the braking test apparatus to figure out the torque profiles. Moreover, the experimental results were compared to the simulation results. This process justified the validity of the proposed mathematical model of the T-shaped MRB. It was investigated that the maximum braking torque from simulations and experimental works were 1.51 Nm and 1.91 Nm at 1 A, respectively. Overall the between differences of simulations and experimental works were about 10%. It is therefore, the mathematical model can be used for further application in the actuator control system.