VIBES: Vibro-Inertial Bionic Enhancement System in a Prosthetic Socket

Abstract

The use of vibrotactile feedback is of growing interest in the field of prosthetics, but few devices fully integrate this technology in the prosthesis to transmit high-frequency contact information (such as surface roughness and first contact) arising from the interaction of the prosthetic device with external items. This study describes a wearable vibrotactile system for high-frequency tactile information embedded in the prosthetic socket. The device consists of two compact planar vibrotactile actuators in direct contact with the user's skin to transmit tactile cues. These stimuli are directly related to the acceleration profiles recorded with two IMUS placed on the distal phalanx of a soft under-actuated robotic prosthesis (Soft-Hand Pro). We characterized the system from a psychophysical point of view with fifteen able-bodied participants by computing participants' Just Noticeable Difference (JND) related to the discrimination of vibrotactile cues delivered on the index finger, which are associated with the exploration of different sandpapers. Moreover, we performed a pilot experiment with one SoftHand Pro prosthesis user by designing a task, i.e. Active Texture Identification, to investigate if our feedback could enhance users' roughness discrimination. Results indicate that the device can effectively convey contact and texture cues, which users can readily detect and distinguish.

Haptic Sensation Enhancement via the Stochastic Resonance Effect and Its Application to Haptic Feedback for Myoelectric Prosthetic Hands

“…In the past, a simple transducer attached to a small speaker [4] was proposed, and in recent years, Ueda et al have transmitted the warmth or coldness of an object by transmitting the temperature detected by a temperature sensor at the fingertip to a device on the upper arm [5], Osborn et al developed electronic skin, which can transmit pain to the user by detecting differences in the shape and texture of objects at the fingertips and sending signals to peripheral nerves [6], and various other skin sensations can now be transmitted. Alessia et al measured the acceleration of the fingertip and controlled the oscillator of a socket to enable discrimination of roughness [7], Christian et al detected pressure from a silicon bulb and confirmed that the magnitude of pressure could be discriminated by inflating the silicon pad at the cut using a monofilament [8].…”