Design, finite element and experimental analysis of piezoelectric tactile sensors for endoscopic graspers

This dissertation reports on the design, experimentation and the finite element analysis of a prototype PVDF endoscopic tooth-like tactile sensor capable of measuring the compliance of a contact tissue/sensed object. Present day endoscopic graspers are designed tooth-like in order to grasp slippery tissues, but do not measure tissue tactile properties like force and softness. The main objective of this study is to design and model a sensor capable of measuring the total applied force on the sensed object as well as compliance of the tissue/sensed object. The sensor consists of a rigid and compliant cylindrical element. Determination of the compliance of sensed objects is based on the relative deformation of contact object/tissue on the compliant and rigid elements of the sensor. A PVDF film is sandwiched between rigid cylinder and plate, which measures the force applied on the rigid element. Another PVDF film is sandwiched between the two base plates to measure the total force applied on the sensor.; Using 2D finite element analysis, the tissue has been modeled as an elastic beam on rigid and elastic foundations and the results are compared with 3D ANSYS model. (Abstract shortened by UMI.)...