Dipartimento di Ingegneria informatica, automatica e gestionale

This paper proposes an approach for displaying the needle-tip interaction force exchanged between the needle tip and the tissues to the remote operator of a teleoperated needle insertion procedure. As known, the measures of the needle tip interaction force with tissues obtained through F/T sensor at the robot wrist do not provide a transparent perception of the needle-tissue interaction at the tip mainly because of the friction between the needle shaft and the traversed tissues. Current literature mainly proposes hardware solutions to the problem of measuring the forces at the needle tip. In this work we aim instead at cleaning the F/T sensor information for rendering only the estimated force exchanged at the needle tip. The approach is based on an online identification of the parameters of a needle-tissue interaction force model to isolate offset force values mainly due to friction. The approach, validated through simulations and experiments, is expected to increase the sensitivity of the rendered force to tissue transitions thus improving safety and accuracy in needle placement.