Haptics for Robot-Assisted Minimally Invasive Surgery

For centuries, open surgery was the standard for performing an operation on a patient. In cardiac surgery, for example, a sternotomy is performed in which a surgeon saws open the patient's sternum to access the heart and create an operable space. This technique is traumatic for the patient and results in large scars and lengthy, expensive recovery time. In the last several decades, minimally invasive surgery (MIS) has revolutionized the way surgeries are performed and met patients demand for smaller incisions and shorter recovery times. Surgeons can perform many of the same surgeries as open surgery using an endoscope and specialized instruments that fit in natural openings in the body or through keyhole incisions (typically 5-12 mm in diameter) instead of creating large incisions. The advantages of MIS procedures include decreased pain, shortened recovery time, and reduced scarring for the patient [3]. While traditional MIS techniques have numerous benefits for patients over open surgery, they create several drawbacks for the surgeon. Images are captured from the endoscopic camera and displayed on a 2D monitor causing surgeons to loose depth perception in the operating field. The surgeon also experiences higher fatigue from holding rigid instruments that are controlled at a distance (known as the fulcrum effect). The counter-intuitive motion of the instrument pivoting about the incision point requires the use of mirrored motions from that of the operating field. Finally, MIS feels significantly different from open surgery because the long-shafted instruments needed to operate through the small incisions deprives the surgeon of direct haptic sensation. (In this paper, we use the word haptics to generally describe touch feedback, which may include both force/kinesthetic and tactile/cutaneous feedback.) Numer