Spatial motion constraints for robot assisted suturing using virtual fixtures.

We address the problem of the stitching task in endoscopic surgery using a circular needle under robotic assistance. Our main focus is to present an algorithm for suturing using guidance virtual fixtures (VF) that assist the surgeon to move towards a desired goal. A weighted multi-objective, constraint optimization framework is used to compute the joint motions required for the tasks. We show that with the help of VF, suturing can be performed at awkward angles without multiple trials, thus avoiding damage to tissue. In this preliminary study we show the feasibility of our approach and demonstrate the promise of cooperative assistance in complex tasks such as suturing.