Glove- and Sleeve-Format Variable-Friction Electrostatic Clutches for Kinesthetic Haptics

Clothing with integrated high-force actuators enables wearable haptics for immersive virtual reality (VR) and enables soft exoskeletons for rehabilitation or human augmentation. Electrostatic clutches (ESClutches) offer a very-low-energy solution to block motion and are mm thin. Challenges for ESClutches in wearables are 1) effective integration in clothing to accurately block body motion while ensuring comfort, 2) well-controlled sliding for variable stiffness rendering, and 3) adaptation to shoulder or hip joints. Here, the control of sliding friction of soft ESClutches is demonstrated, using materials that enable both integration in textile and efficient force transfer to the user. We present a 1.3 mm-thick soft glove with five ESClutches, providing up to 50 N of kinesthetic feedback per finger. A clutch in a thin haptic sleeve that controls elbow extension is reported. Eight cable-format ESClutches on a shoulder are shown, selectively blocking multiple degrees of freedom. VR tests demonstrate that the glove and the sleeve give the user the ability to rank the softness and weight of virtual objects. In a teleoperation scenario, the glove enables the user to remotely feel an object's stiffness. The ESClutches and textile integration pave a path toward socially acceptable and comfortable kinesthetic haptics.