Compliant mechanism for providing stepwise clicking haptic feedback

摘要

A compliant mechanism is provided, for extending a rod in a manually controlled instrument and providing clicking haptic feedback, such as in particular in a compliant surgical grasper. The compliant mechanism comprises an inner rod that comprises an upper slit and a lower slit running through a section of the rod, that forma generally S-shaped cut in the rod, such that when ends of the rod are pulled at the S-shaped form allows an extension of the rod in the axial direction by compliant bending; the mechanism comprises a notch placed on the outer surface of the rod, adjacent to a respective slit opening and on the proximal side of the opening, and an outer sleeve enclosing the inner rod, the sleeve having on its inner surface one or more groove or teeth facing the at least one notch on the rod surface, such that when the rod is extended, the notch engages with said groove or tooth to create a clicking haptic feedback.