A flexible high-fill-factor haptic interface integrating electrostatic valves

We report a compliant haptic interface with 6 inflatable 8 mm diameter bubble shaped bumps that the user explores with their finger. One single air supply controls 6 bubbles by using integrated electrostatic valves (ESValves) to independently lock each bumps in the up or down position. Applying a high voltage to the electrodes for a given bubble generates an electrostatic force that closes off the air channel at the entrance to only that bubble, enabling independent control over the inflation and deflation of individual bubbles. In comparison to previous HAXELs (Hydraulically Amplified Taxels) from our lab, this design achieves a 3x higher fill factor of 60%, but requires an air supply. The soft, thin structure allows for integration on curved surfaces and scalability for diverse applications.