Jonathan Kim

The mechanism and registration method of a surgical robot for hip arthroplasty

This paper presents the mechanism and surgical method for ARTHROBOT, a new surgical robot for hip arthroplasty. The robot is femur-mountable and capable of 4-DOF motion. It uses a new gauge-based registration method that utilizes measuring instrument consisting of a reamer-shaped block gauge and a distance-measuring device. This gauge-based registration method drastically reduces the processes in the preoperative planning by eliminating the need of inserting fiducial markers or CT scanning. From the preliminary performance evaluation, it is shown to have less than 0.3 mm machining error, which seems to be sufficiently accurate for clinical application. Since the system has low operating cost and is compatible to the conventional manual surgery, it is expected to be easily adaptable to surgical needs and practices in the operating room.

Design of a compact 5-DOF surgical robot of a spherical mechanism: CURES

In recent years, several surgical or assistant robots have made a successful debut to surgical theatre. Due to their large size, and high price, there is a growing need for the miniaturization of these surgical robots. In this paper, a design methodology for a compact surgical robot is presented. Considering workspace and force requirements, a simulation and experiments are conducted to determine the design parameters. The compact surgical robot CURES of 5-DOF spherical mechanism is developed from the analysis and its properties are presented.

Compact laparoscopic assistant robot using a bending mechanism

This paper presents the development of a compact laparoscopic assistant robot. The robot was designed to increase convenience and reduce possible interference with surgical staff by confining the majority of motions inside the abdomen. Its size was miniaturized as much as possible for convenient handling. A bending mechanism composed of several articulated joints was introduced to produce motions inside the abdomen. The proposed assistant robot can generate 3-DOF motion, including 2-DOF internal bending motion and 1-DOF external linear motion. Since the robot itself functions as a laparoscope, a small CCD camera module and a bundle of optical fibers were integrated as part of the system. For accurate control, mathematical modeling of the bending mechanism and a method of hysteresis compensation were introduced and implemented. For the control of the robot, a voice interface and a visual-servoing method were implemented. The performance of the developed system was tested through solo-surgery of in vivo porcine cholecystectomy. It was found that the views generated by the bending mechanism were sufficient throughout the surgery. Since the robot has functions comparable to the previously developed systems, while retaining its compactness, it is expected to be a useful device for human cholecystectomy.

Compact camera assistant robot for minimally invasive surgery: KaLAR

This paper describes the development of a compact laparoscopic assistant robot system which functions as a camera assistant in laparoscopic surgery. The system allows 3-DOF motion and is mountable to a standard laparoscope holder. The 3-DOF motion includes 1-DOF translation and 2DOF bending motion for adjusting viewpoints. This compact system is designed so that viewing angles are adjusted within the abdomen using a bending section and thus, interference with the operating surgeon is reduced. Voice-controlled command input and visual-servoing are implemented for the control of the robot. Our preliminary experiments show a possible clinical use upon further improvement.

Intelligent interaction between surgeon and laparoscopic assistant robot system

This paper proposes an intelligent interaction architecture to develop a compact robotic assistant which is operable with minimal control burden. The interaction architecture provides the viewpoint of a laparoscope based on a surgery model and environmental information and an operating surgeon can modify the viewpoint with voice commands, if needed. For this purpose, cholecystectomy is modeled with state-transition diagram through the analysis of four human cholecystectomies. The surgery model for the laparoscopic assistant robot includes a sequence of surgical procedures, surgical instruments in use and proper camera view point at each stage. The camera view information is utilized to obtain the tip position and the type of surgical instrument in use. Surgeons voice commands are used to modify the camera view suggested by the proposed architecture. The proposed interaction scheme is implemented using the KaLAR system and evaluated through in vivo porcine cholecystectomy.

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

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

Intelligent Control of a Laparoscopic Assistant Robot Based on the Surgical Task Model

This paper proposes a surgical task model for developing an intelligent control method for a laparoscopic assistant robot. The proposed model makes the use of surgical knowledge composed of surgical procedure, tool information, desired view and preferred control method at different phases of surgery. For establishing the surgical task model, procedures in human cholecystectomy are analyzed. It was found that there are specific task and action associated with a specific tool and certain views are preferred by the surgeon. It was also found that the surgeon prefers the assistant to stay steady while manipulating the tissues or organs whose motions are constrained by anatomical features while they prefer the assistant to track the tool tip when there are relatively limited constraints. The interaction scheme based on this surgery task model is implemented using a compact laparoscopic assistant robot and its performance was compared to the in vivo porcine cholecystectomy using voice commands alone.

In vitro study using cadavers for evaluation of a bone-mountable surgical robot system

This paper describes a bone-mountable surgical robot system for hip surgery and its in vitro experiments with cadavers. The system eliminates the need for obtaining CT scan data by adopting gauge-based, bone-mounting registration method and is designed to replace only the broaching procedure, which is known to be the most error-prone procedure in the manual surgery. The performance of this system is evaluated with specimen of six human cadavers. X-ray images and photographed image of femurs are utilized for measuring the difference between the implant and the anatomical axes. As this deviation implies how the gait pattern of the operated patient may be influenced by the surgery, the amount of deviation is used as the indicative of system performance. The nominal differences of anteversion angle, valgus-varus angle, and flexion-extension angle are 0.02/spl plusmn/2.73/spl deg/, 0.98 /spl plusmn/0.39/spl deg/ and 0.51/spl plusmn/0.87/spl deg/, respectively. In case of the change in leg length after the surgery, the nominal error is -0.88/spl plusmn/1.26 mm. Experimental results show that the performance of the developed system is comparable to other surgical robots that use preoperative planning with CT scan data.