An actuator for the tactile vest - a torso-based haptic device

Our goal is to design a robust, versatile actuator for a Tactile Vest, a wearable device that provides haptic feedback to the torso. The technology we propose to use as the actuator for this device is Nitinol, a shape memory alloy (SMA). Nitinol is capable of generating large stresses and strains, but is small and flexible and able to fit in the thin, dynamic workspace of a vest. In experimental tests conducted on the SMA, a pulse 1 A in amplitude and 1 s in duration produced an average displacement of 3.7 mm and peak pressures about 20 times the touch threshold for the torso. These results indicate promise in using Nitinol to create a torso-based haptic device that can generate a wide range of stimuli, yet is comfortable to the point of being invisible to the user until a stimulus occurs.