Design of compact magnetorheological actuator with double disk, double coil

Teleoperated robotic systems are widely used in daily life, but the actuators in their force feedback devices suffer from large structure volume, poor stability, low feedback torque and slow response speeds. Based on the magnetorheological (MR) effect, a double-coil and double-disk MR damper structure is proposed in this paper. According to the constitutive model of MR fluid, the torque mathematical model of double coil and double disk MR damper is established. Based on the orthogonal experiment method, the material and geometry of the magnetic circuit are selected through the dynamic response range analysis and sensitivity analysis, the magnetic circuit is designed by the equivalent reluctance method. Through the simulation of the steady magnetic field of the MR damper, the rationality of its structural design is verified. A prototype of the MR damper was built, and its performance was verified through experiments. The results show that the damper has a torque adjustment range from 20 N<middle dot>mm to 780 N<middle dot>mm, output torque fluctuation of 3.33% and response time of 50 ms. It means that the damper has the characteristics of wide torque adjustment range, compact structure, stable output and fast response speed. Therefore, the damper has significant application potential in force feedback device.