OUCH: Objective, Uniform, Controlled Haptic Stimulation Wrist-Worn Device for Automated Neurological Assessment

OUCH is a wrist-worn pneumatic haptic stimulation device that uses stacked pneumatic pouch actuators, a rigid indenter, and a compliant spacer designed to buckle at a set load, so that the indenter contacts the skin only during actuation. At 200 kPa pouch inflation pressure, its indenter's contact pressure is estimated to reach 18,500 kPa, more than 25 times that of a commercially available handheld pressure algometer tip, while requiring less total force. In preliminary perceptual testing, the force required for this indenter to elicit discomfort was about 89% lower than that of the pressure algometer, providing a basis for controllable, repeatable noxious stimulation at the wrist.