Assistance to bone milling: a tool mounted visual display improves the efficiency of robotic guidance

In this paper, a new kind of assistance for bone milling is disclosed. It combines a robotic comanipulator applying forces to guide the milling tool tip with a visual display mounted on the hand-held tool. This visual display is a LED bargraph providing to the user a geometric information that is mostly redundant with the forces exerted by the robot, thus constituting a multi-modal feedback. Although very basic and rather inexpensive, the additional visual display is experimentally shown to significantly improve the precision of the gesture.