Modelling and simulation of a new magnetorheological linear device

Interaction between humans and robots is expected to increase in the coming years. In order to ensure safety for the robot, its environment, and the people around it, it is necessary to have robust compliance actuation. Mechanically compliant devices such as magnetorheological actuators can ensure a high degree of safety through their intrinsic properties. This paper presents the modelling of a new kind of magnetorheological piston intended for linear actuation. An analysis using the reluctance method and an approximation of the Buckingham Reiner equation are used to develop the electromagnetic and hydraulic equations respectively, and key parameters of the system are presented. A simulation is done to evaluate the theoretical performance of the new piston design, its results are compared and validated by the experimental data obtained from a prototype. The simulation results show the capacity of the device for compliant actuation.