A review of force and resonance sensors used in the clinical study of tissue properties.

Tactile sensing is commonly carried out by humans using their fingers or hands to estimate the physical properties of an object. A large body of literature covers a range of applications of these methods in clinical situations. The objective of this work is to show the breadth of application areas explored and the achievements that have been made in the measurement of physical variables of interest to physicians using tactile force and resonance sensors. Although a broad spectrum of applications has been considered, of particular interest is the application of these methods to determine tissue properties in vivo. Progress in this direction has been made by various groups particularly with respect to piezoelectric and capacitance sensors. Also described are the findings of a preliminary study of a tactile system designed to examine the abdomen of the clinically super-obese patient.