A body-mounted surgical assistance robot for minimally invasive spinal puncture surgery

Robotic surgical assistant systems can transcend the precision of surgical procedure by integrating the position information of patient and robot in the surgical room. There are two conventional integration methods, the real-time position tracking and physically fixing. In clinical cases, the former has the problem of increasing radiation exposure; so physical fixation is more commonly used in robotic surgery. However, the conventional fixing methods are also not optimized and problems of invasiveness and rigidness of fixation are left unsolved. This paper deals with a body-mounted surgical assistance robotic system for percutaneous vertebroplasty. The robot is fixed on the human body surface by fixing device that utilizes jamming transition phenomenon and vacuum cup. The body-mounted robot system sets up the correct pathway for needle insertion. The system was fixed on human shape target with a 166±8 N suction force. The fixing rigidity of our system and accuracy of the needle guide control device has been evaluated by measuring the displacement during needle inserting operation. The displacement of the fixing device by the external force of needle inserting operation was 0.06 mm and 0.02° in RMS. The total displacement of needle guide was 1.66 mm and 1.24° in RMS. The total positioning error of the needle guide control device was 0.09 mm and 0.97° in RMS.