Magnetorheological Fluid Based Torque Transmission Clutches

Abstract

Applications of magnetorheological (MR) fluids in torque transmission clutches are investigated in this study. Quick time response and variable rheological properties of MR fluids in response to an applied magnetic field are utilized in generating the variable torque transmission. Magnitude of the transmitted torque is adjusted by the level of the magnetic field applied over the MR fluid in the clutch mechanism. In this experimental study, the MR torque transmission clutch configuration considered was based on a concentric cylinder geometry. The MR clutch was fabricated and tested during the study. An experimental set-up was prepared based on a power motor, magnetic field generation system, and the MR clutch mechanism. Coiled wires in a solenoid configuration were used to generate the magnetic field. The wires were coiled over the clutch housing and electric current was sent to the wires. The electric current level determined the magnitude of the applied magnetic field. The clutch cylinders were sealed and the space in between the cylinders was filled with the MR fluid. By driving the clutch with the power motor, and applying varying magnetic field levels, variations in the transmitted torque was obtained. Continuous measurements were made between the input and output power and the transmitted torque for different magnetic field levels and different motor speeds. The torque transmission capabilities of MR clutch configurations were evaluated from the study. MR clutch mechanisms can potentially be used in underwater robotic systems where controlled continuous torque transmission is desirable.