Real time robotic tactile sensor system for the determination of the physical properties of biomaterials

A novel tactile sensor system, specifically designed to detect and quantify in real time tissue characteristics in a manner analogous to the human hand, is presented. To date, no modality that is capable of detecting the hardness and/or softness of tissues has been developed. The emerging requirement to build smart robotic manipulation for the next generation of virtual systems, incorporating hand-like-tactile feedback, continues to challenge developers in biomedical instrumentation. To satisfy this need we present a novel sensor system, consisting of a combination of a piezoelectric transducer (PZT) and a pressure sensor element. The system is designed with a feedback circuit, made with a disc-shaped PZT sensor element and a phase shift circuit acting as the oscillating circuit. Upon contact with a test object, this system responds to its physical properties by changing its resonance frequency in accordance with the object's acoustic impedance. It is suggested that this sensor may prove useful in applications involving robotics in the biomedical field and can be incorporated in the next generation of virtual operating systems. (C) 2004 Elsevier B.V. All rights reserved.