Design and Preliminary Evaluation of a Handheld Compliant Robot for Membrane Peeling Using Negative Pressure Adsorption

In retinal surgery, membrane peeling is a challenging procedure that requires surgeons to limit peeling force and manage disturbance force at the millinewton level. This article presents a novel handheld compliant robot designed to assist in membrane peeling, featuring a five-chain parallel compliant module and a force-sensing tube. The compliant module is used to adjust the tip's transverse position actively, while the tube is designed to adsorb the membrane and sense the peeling force. The Jacobian matrix of the proposed robot is also derived. Then, a data process method based on wavelet decomposition and Kalman filtering is introduced to identify the disturbance force. A control method based on the Jacobian matrix is also proposed to compensate the disturbance force. Finally, the proposed robot is evaluated through bench test and handheld test, in which chicken chorioallantoic membrane is utilized as the ex-vitro model. The handheld test results show that the root mean square and maximum of disturbance force are reduced by 44.1% and 52.7%, respectively. The membrane detaches from the tube when the peeling force approaches 15 mN, which provides a passive safety guarantee of membrane peeling.