Application of Electro-Rheological Fluids for Conveying Realistic Haptic Feedback

Abstract

For a device to convey realistic haptic feedback, two touch sensations must be present: tactile feedback and kinesthetic feedback. Tactile feedback consists of the sensations felt at the surface of one’s skin and just underneath it, while kinesthetic feedback is felt in one’s joint and muscle nerves and provides information about position and movement. Though many haptic devices today convey tactile feedback through vibrations, most neglect to integrate kinesthetic feedback. To address this issue, this study investigates a haptic device with the aim of conveying both kinesthetic and vibrotactile information to users. To this end, a prototype device based on Electro-Rheological (ER) fluids was designed and fabricated. By controlling the ER fluid flow with the use of varying electric field strengths, the device can generate various haptic sensations. The design focused around an elastic membrane that acts as seal and the actuator’s contact surface. Moreover, the control electronics and structural components were integrated into a compact printed circuit board to miniaturize the device. The device was then tested using a dynamic mechanical analyzer (DMA) to evaluate its performance. During the experimental evaluation, the actuator’s resistive force along with the indented depth up to 1 mm were measured by varying the input voltage magnitude, frequency, as well as wave profiles. The results indicate that a range of possible force (kinesthetic) and vibrational (tactile) sensations were produced based on input voltage signals. According to the Just-Noticeable Difference (JND) analysis, this range is sufficient to transmit distinct kinesthetic and vibrotactile sensations to users, indicating that the ER haptic device is capable of conveying realistic haptic feedback.

Publication
ICAST 2018