Design of a Magnetically Anchored Laparoscope Using Miniature Ultrasonic Motors

Images taken by an endoscope in single-port-access surgery are the most important information for directing surgeons to operate, so acquiring images taken at better position and a more desired perspective has profound significance for improving the efficiency and safety of surgery. The magnetically anchored laparoscope can help to realize this goal compared with the traditional laparoscope used in single-port-access surgery. In this paper, we propose the concept of applying ultrasonic motors in the magnetically anchored laparoscope. Two types of ultrasonic motors used for driving the laparoscope, namely a miniature traveling wave-rotating ultrasonic motor and a miniature traveling wave-tilt ultrasonic motor, are designed. The prototype of the magnetically anchored laparoscope using these two types of ultrasonic motors is fabricated and evaluated by experiments. The results show that the maximum output torque of the miniature traveling wave-rotating ultrasonic motor is 1.2 mN·m, and that of the miniature traveling wave-tilt ultrasonic motor is 1.4 mN·m, which is enough to actuate the magnetically anchored laparoscope. Additionally, it is proven that the two designed ultrasonic motors can be applied successfully in the laparoscope.