4-DoF spherical parallel wrist with embedded grasping capability for minimally invasive surgery

This paper presents preliminary results of a new robotic wrist for minimally invasive surgery. This wrist is a high-dexterity miniature robot, able to provide simultaneously the grasping/cutting (1-DoF) and rotations capabilities with 3-DoF. The grasping function is insured by the folding of the top platform of a parallel structure. The grasping capability of the wrist is part of the mechanical structure itself and can be fully controlled by external actuators. In order to validate this original approach, an experimental prototype has been fabricated using 3D printing technology at a larger scale. The inverse kinematic model has been developed and the workspace analysis was accomplished to assess the capabilities of the realized system. Finally, experimental tests have been also carried out for validating the proposed structure.