Haptic Sensitivity in Compliance Evaluation in a Tool-Wielding Paradigm

Abstract

This paper describes a methodology for establishing standardized tests of haptic sensitivity in a tool-wielding paradigm. A haptic-needle was developed to study compliance differentiation in a needle-insertion task, using a psychophysics experimental protocol. The relationship of applied force and position as a function of perceived tissue compliance was obtained from the recorded data. The Just-Noticeable-Difference (JND) for tissue compliance discrimination with the haptic needle was calculated. Results showed that the JND increased as compliance of the tissue increased. Compliance differentiation was easier when the layers of tissue were more different in compliance. These common trends suggest that the proposed methodology is valid and the haptic performance of human subjects can be quantified.