Design and Kinematics Analysis of a Non-invasive Wearable Haptic Armband for Patients with Prosthetic Hands

Intuitive haptic feedback is a major hurdle that needs to be overcome to deliver prosthetic devices fit for daily use. Current preferred non-invasive feedback methods lack the natural feeling that can be provided by mechanotactile feedback systems. However, these systems are often bulky and cannot serve as a daily life accessory to a prosthetic hand. In this research, we present a wearable non-invasive haptic feedback device designed around the concept of an easy-to-visualize and interpret mapping between the sensation in the prosthetic hand and stimulation provided by the device. The proposed system maps sensation from five fingers in the prosthetic hand to five fingers in the feedback device and is designed to provide the feel of a hand touching the user’s upper arm. The stimulation is cutaneous, targeted at the skin on the upper arm, and, felt as pressure with additional stretching and squeezing cues at high outputs. A model of the device was developed from the kinematic relations and was used to investigate the dependencies and optimize the design parameters in the context of delivering haptic force feedback with desired motion profiles. Our results indicate that the haptic armband is capable of providing feedback that can be customized to meet different user preferences. We expect this device to be an accessory to prosthetic hands for daily life activities, by providing modality-matched haptic feedback.