Discrimination of springs with vision, proprioception, and artificial skin stretch cues

During upper-limb prosthesis use, proprioception is not available so visual cues are used to identify the location of the artificial limb. We investigate the efficacy of a skin stretch device for artificially relaying proprioception during a spring discrimination task, with the goal of enabling the task to be achieved in the absence of vision. In this study, intact users perceive the location of a virtual prosthetic limb using each of four sensory conditions: Vision, Proprioception, Skin Stretch, and Skin Stretch with Vision. For the conditions with skin stretch, a haptic device stretches the forearm skin by an amount proportional to the angular rotation of a virtual prosthetic limb. Sensory condition was not found to significantly influence task performance, exploration methods, or perceived usefulness. We conclude that, in the absence of vision, artificial skin stretch could be used by prosthesis wearers to obtain position/motion information and identify the behavior of a spring.