A reconfigurable haptic joystick based on magneto-rheological elastomers - System design and first evaluation

Abstract

Haptic interfaces with reconfigurable characteristics such as joysticks promise new possibilities for interaction design with increased intuitivity, new functional schemes, and enhanced overall safety. In this paper, we investigate the usage of magneto-rheological elastomers (MRE) as functional materials for a haptic joystick for steering and control applications. MREs provide a base elasticity with an electrically manipulable damping and storage modulus in a dimensionally stable, viscoelastic compound that is especially suited to form an elastic or damping element. We present a basic sequential simulation approach for elastic and magnetic properties to dimension MRE material for actuation use. A commercially available joystick is modified with a reconfigurable compliance based on the optimized MRE actuator. It is able to display varying reaction torques of 0.1 to 0.5Nm for exciting currents of 0 to 4A in a movement range of-20 to 20°. An identification experiment with 21 subjects and 5 different characteristics determines a possible information transfer of 0.828 bit with individual performances as high as 1.62 bit. Based on these results, we conclude that MRE actuators are a promising option for reconfigurable haptic interfaces with technological advantages compared to other actuation concepts.