Dynamic Stimulation Patterns for Conveying Proprioceptive Information from Multi-DOF Prosthesis

The aim of this study was to investigate the ability of the amputees to understand and identify proprioceptive feedback information presented by a set of dynamic stimulation patterns. The feedback relied on spatial coding of electrotactile stimuli, provided by a multichannel electrical stimulator, over custom designed array electrodes. Four stimulation patterns representing opening, closing, pronation and supination of a prosthetic hand were defined to mimic the change of the corresponding prosthesis degree of freedom. The psychometric evaluation on three amputee subjects confirmed that the four proposed dynamic stimulation patterns can be distinguished successfully after a short training.