1 A Foldable Mechanism for Stereo Vision in Laparoscopic surgery

Enhancing the depth perception in laparoscopic surgery is very important. Towards this goal, we have designed a foldable mechanism for mounting two small cameras that enable stereo vision in a laparoscope. The challenge ad-dressed here is to fold the two cameras, the entire mecha-nism, and the actuating wires within a tube of 15 mm di-ameter. The mechanism is pre-loaded with springs so that it will automatically deploy into a desired configuration upon pushing it out of the tube. Furthermore, in the de-ployed configuration, the mechanism can be manipulated by pulling on the actuating wires to change the stereo-base distance between the two cameras for focusing at different depths inside the abdomen. A 2X-scale working prototype has been made and experiments have been conducted on some typical simulated tasks of surgery. The results of the experiments indicate that depth perception improves with the mechanism presented here