Interdisciplinary Network of Researchers in Touch
Thursday 25th July, 2019
|16:30-16:45: Symposium in Lecture Theatre, A01||Mechano-tactile haptic feedback system for 3D printed, body-powered prostheses|
Hands, as one of the most sensitive parts among our bodies, the loss of an upper limb leads to a huge challenge for amputees in their daily life both manipulating and perception. Hence, different prosthetics have been developed in both bionic electromechanical and body-powered actuation method. But worldwide, 80% of total upper limb amputees cannot afford the bionic electromechanical prosthetic hand with their haptic feedback system. Also, the majority of the developed haptic feedback system is electronic with heavyweight and apply vibrotactile sensation to generate the stimulation. Hence, the object is developing a low-cost mechano-tactile haptic feedback system, which is purely mechanically-driven and easy to intergrade into the prosthetic hand, for helping amputees to recover their haptic perception. Based on the object, we proposed the hydraulic haptic feedback system that can generate mechano-tactile stimulation. This is a system contain two main components: 1) Fingertip sensor can sense the bearing force of the prosthetic finger. 2) The feedback actuator is aimed to generate mechano-haptic stimulation. Both fingertip and feedback actuator is connected with a pipe to form a closed cavity and fully filled with water. After the soft fingertip being pressed, the internal liquid pressure increased, and the feedback actuator is swelling to generate the mechano-tactile stimulation. Based on the concept, the prototype of the hydraulic haptic feedback system has been produced by 3D-Printing and was tested. The maximum force stimulation is 2.1N when the fingertip suffering 13.8N. Also, the system has been tested with healthy volunteers to determine the median touch threshold, which is around 0.2N. Overall, the system can generate the mechano-tactile simulation to users and recover the haptic perception to an extent.