Piezoelectric Tactile Tissue Differentiation Sensor System: Concepts and Measurement Challenges

In this contribution the development of a piezoelectric
tactile sensor system for the differentiation of soft tissues
and phantoms is presented. The aim of this system is to
provide a medical tool that can help neurosurgeons with
the critical task of brain tumour resection, where in
particular, the most important characteristic is to offer the
surgeon the capability to find accurately tumour
boundaries during surgery. The differentiation among
distinct tissues and phantoms that have similar mechanical
characteristics is a technique based on the detection and
evaluation of different electrical parameters, where
frequency response function measurements utilizing
multisine excitation are performed to obtain the transfer
function of the bimorph's voltages USensor/UActuator. The
system was tested on a series of gelatine gel phantoms at
different concentrations. The bimorph sensor system is
able to detect even minimal differences.