MR-brakes have very desirable characteristics but they also have hysteresis behavior. The hysteresis creates control challenges and significant residual off-state torque which prevents use of high gear ratios with MR-brakes.
We developed a novel control scheme with an embedded sensor.
Funded by a grant from the National Science Foundation.
United States Patent: Magnetorheological Devices and Associated Control Methods, U.S. Patent 9,093,214 B2, July 28, 2015
- “Magnetic induction control with embedded sensor for elimination of hysteresis in magnetorheological brakes,” Journal of Intelligent Material Systems and Structures, vol. 23, no. 4, pp. 426-439, 2012.
- “Virtual needle insertion with haptic feedback using a hybrid actuator with DC servomotor and MR-brake with Hall-effect sensor,” Mechatronics, vol. 22, 2012.