Intelligent Laparoscopic Assistant Robot through Surgery Task Model: How to Give Intelligence to Medical Robots

Abstract

Laparoscopy has become one of the most popular surgical techniques since the 1990s due to its surgical effectiveness, fast recovery and good cosmetic outcome. From simple to more complex surgeries, the proportion of laparoscopic to open procedures is continuously increasing. Due to small incision, patients can regain health without much trauma and hospitalization; however, the operating surgeons suffer from limited range of motion, reduced flexibility, loss of tactile sensation and limited depth perception compared to open surgery. One of the important issues for successful surgery is the cooperation between the operating surgeon and the assistant as it is directly related to how the surgeon can perform surgical tasks. Manipulating vessels and organs using long tools without direct visual feedback requires utmost attention and the assistant should maneuver the laparoscope without disrupting the operating surgeon. Novice assistants often suffer from: (a) the difficulty in properly positioning the laparoscope in three-dimensional space based on the projected images on a monitor, (b) the presence of the fulcrum effect at the trocar insertion point, and (c) the hand tremor caused by fatigue. To alleviate the effect of these difficulties, some surgical robotic systems (Franzino, 2003; Ghodoussi et al., 2002; Guthart & Salisbury, 2000; Mitsuishi et al., 2003) and laparoscopic assistant robot systems such as AESOP(Wang et al., 1996), EndoAssist(Finlay, 1996) and so forth(Berkelman et al., 2002; Kobayashi et al., 1999; Taylor et al., 1995) were developed. Despite the applicability in real surgeries, these systems exhibit some common limitations or constraints that should be resolved. These systems are known to occupy a voluminous space in the operating room and the external motion of links tends to interfere or come in close contact with the surgeon and surgical staff. In order to develop a compact robot and to reduce possible interference with surgical staff, we adopted an internally bending mechanism. This internally bending mechanism confines the majority of motions inside the patient’s abdomen and also reduces the size of the robotic system. The proposed laparoscopic assistant robot system, KaLAR (KAIST Laparoscopic Assistant Robot), will be explained in detail later. Although most of the robotic assistants can substitute for the role of human assistant, clinical studies revealed that a considerable number of voice commands are needed to control the robot, while only a handful of voice commands is sufficient with a human O pe n A cc es s D at ab as e w w w .ite ch on lin e. co m