Design of a new cable-driven manipulator with a large open lumen: Preliminary applications in the minimally-invasive removal of osteolysis

A dexterous manipulator (DM) with a large open lumen is presented. The manipulator is designed for surgical applications with a preliminary focus on the removal of osteolysis formed behind the acetabular shell of primary total hip arthroplasties (THAs). The manipulator is constructed from two nested superelastic nitinol tubes enabling lengthwise channels for drive cables. Notches in the nested assembly provide reliable bending under applied cable tension producing kinematics that can be effectively modeled as a series of rigid vertebrae connected using pin joints. The manipulator is controlled in plane with two independently actuated cables in a pull-pull configuration. For the purpose of the procedure, the manipulator is mounted on a Z-θ stage adding a translational and rotational degree of freedom (DOF) along the axis of the manipulator. Preliminary experimental results demonstrate the initial modeling and control of the manipulator.