Hydraulically Amplified Electrostatic Taxels (HAXELs) for Full Body Haptics

The ability to mechanically stimulate touch receptors over the entire body is a key feature for fully immersive and highly realistic virtual reality experience. Haptic stickers, flexible arrays of HAXELs (hydraulically amplified TAXels), that enable cutaneous haptics over nearly all parts of the body, are reported. HAXELs are zipping electrostatic actuators that combine stretchable elastomers and high permittivity flexible films to generate both high strains and high forces, from DC to 200 Hz. A fabrication process that enables scaling HAXELs from 2 to 15 mm in diameter is presented, allowing to tailor the actuators to different body parts and to wearables such as wrist-watches. The different sizes of HAXELs generate blocked forces from 100 to 800 mN, with DC displacements from 100 to 850 mu m, well above sensation thresholds. Haptics tests of Haptic Stickers, 5 x 5 arrays of 10 mm diameter devices, on palms, back of the hand, neck, arm, and back of a dozen volunteers, are done with users reporting high pattern recognition success on many body locations. The Haptic Stickers uniquely offer a thin and lightweight form-factor, which does not limit the freedom of motion of the user, compatible with untethered scenarios.