Active wrists endoscope navigation in robotized laparoscopic surgery

This paper is focused on the motion control problem for a laparoscopic surgery robot assistant with an actuated wrist. These assistants may apply non-desired efforts through the patient abdomen. Therefore, this article studies these efforts, which have been measured by a force sensor located between the wrist and the endoscope, and how to remove gravity and friction actions in order to obtain the abdominal efforts. The measure of these efforts indicates if the movements are done accordingly to the fulcrum point. To achieve this goal, a new control strategy, based on the emulation of passive wrists behavior, is proposed. Such methodology allows the assistant to minimize efforts over the patient. Finally, this work presents the advantages of actuated wrists for possible future applications.