An experimental investigation of the distributive tactile sensing method applied to discriminate contact and motion of a flexible digit typical of invasive clinical environments

While minimal access procedures in surgery offer benefits of reduced patient recovery time and after pain, for the surgeon the task is complex as both tactile and visual perception of the working site is reduced. In this paper, experimental evidence of the performance of a novel sensing system embedded in an actuated flexible digit element is presented. The digit is envisaged to be a steerable tip element of devices such as endoscopes and laparoscopes. This solution is able to retrieve tactile information in relation to contact with surfaces and to feedback information on the shape of the flexible digit. As such the scheme is able to detect forces acting over the digit surface and can discriminate different types of contact, as well as to evaluate force level, force distribution and other quantifiable descriptors. These factors, in terms of perception, could augment processes in navigation and investigation through palpation in minimal access procedures. The solution is pragmatic, and by virtue of its low mechanical complexity and polymer construction, it offers a real opportunity for maintaining high sterility through disposability and application in magnetic environments such as magnetic resonance imaging.