• 대한기계학회논문집A
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• 제27권6호
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• pp.954-959
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• 2003

Colonoscopy is an important medical procedure for the diagnosis of various diseases like cancers in the colon and rectum. But it requires a lot of time for a doctor to acquire dexterous skills necessary to perform successful colonoscopy. Moreover, to many patients, conventional colonoscopy simply takes too long time. Therefore, some studies on the development of autonomous and more convenient colonoscope are carried out. In this Paper, we Propose a functional colonoscope robot system that has a locomotive function with a hollow body, a steering system, and other basic functions of typical conventional colonoscope systems. The concept and each component of the functional colonoscope system are described in this paper. In order to evaluate the functional performance of the colonoscope robot, we carried out in -vitro and in-vivo tests.

• 대한기계학회논문집A
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• 제26권8호
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• pp.1638-1644
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• 2002

A novel locomotion using the pneumatic impulsive actuator was proposed for robotic colonoscope. This locomotion showed good moving performance in the environment of rigid pipe, however, the displacement per one impact(step displacement) is greatly reduced due to the low stiffness and high damping characteristics of the colon. Therefore, the modeling technique based on spring and damping system is studied to predict the step displacement and some parametric studies are carried out to investigate main parameters that influence the step displacement of locomotion. Based on simulation result, a new locomotion to control the resistance force is suggested and fabricated. Through the experiment on the colon, the usefulness of modeling technique is confirmed and successful improvement of moving characteristics is achieved.

• 제어로봇시스템학회논문지
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• 제8권4호
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• pp.345-350
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• 2002

In recent years, as changing the habit of eating, the pathology in the colon grows up annually. The colonoscopy is generalized, but if requires much time to acquire a dexterous skill to perform an operation and the procedure is painful to the patient. biomedical and robotic researchers are developing a locomotive colonoscope that can travel safe1y in colon. In this paper, we propose a new actuator and concept of semi-autonomous colonoscope. The micro robot comprises camera and LED for diagnosis, steer- ing system to pass through the loop, pneumatic actuator and bow-shaped flexible supporters to control a contact force and to pass over haustral folds in colon. For locomotion of semi-autonomous colonoscope, we suggest an actuator that is based on impact force between a cylinder and a piston. In order to validate the concept and the performance of the actuator, we carried out the simulation of moving characteristics and the preliminary experiments in rigid pipes and on the colon of pig.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.57-61
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• 2005

This paper presents a new colonoscopy training simulator that includes a specialized haptic device and graphics algorithms to transfer haptic sensation through a long and flexible tube, and manage large number of polygons. The developed haptic device makes the colonoscope tube move along the two guiding rods in the translational direction. The torque of the roll motion is transferred by a timing belt and pulleys. A special guide is developed, which allows the force and torque from the motors to be transmitted to the user without loss. The haptic device is evaluated by physicians. One of the important skills of the colonoscopy, jiggling is incorporated for the first time by the developed sensor mechanism using photo-sensors. A colonoscope handle that shares the look, feel, and functions with the actual colonoscope, is developed with the necessary electronics inside. The number of polygons is reduced by an edge-collapse algorithm for real-time simulation. The algorithms to import CT data, to segment the colon image, to extract centerline of the colon, and to construct the colon surface, are integrated into a Colon Modeling Kit system that performs all these processes in real-time.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집B
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• pp.295-300
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• 2001

In recent years, as changing the habit of eating, the pathology in the colon grows up annually. For that reason, the colonoscopy is generalized. But it requires much time to acquire a dexterous skill to perform an operation. And the procedure is painful to the patient. Therefore, biomedical and robotic researchers are developing a locomotive colonoscope that can travel safely in colon. In this paper, we propose a novel design and concept of semi-autonomous colonoscope and two actuators for the micro robot. The micro robot comprises camera and LED for diagnosis, steering system to pass through the loop, pneumatic actuator and bow-shaped flexible supporters to control a contact force and to keep the space between colon wall and the actuator. For actuating mechanism, we suggest two models. One is based on the reaction force, and the other is impact force. In order to validate the concept and the performance of the actuators, we carried out the preliminary experiments in rigid pipes.

• 대한기계학회논문집A
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• 제26권7호
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• pp.1296-1301
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• 2002

In recent years, the pathology in the colon grows up annually since people of all ages prefer to have less fiber and more fat food. Therefore, the colonoscopy is generalized in developed countries. But it requires much time to acquire a dexterous skill to perform an operation and the procedure is painful to the patient. Therefore, some studies on the development of autonomous colonoscope are carried out. In this paper, we propose a new and simple locomotive mechanism that can be propelled by elliptic motion of a leg. It has several legs that have constant phase difference each other and those legs are disposed along the upper and lower of the body. In order to evaluate the performance of locomotive mechanism, we carried out the simulations of moving characteristics and the experiments in the colon of a dead pig.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집B
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• pp.271-276
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• 2001

Conventional clonoscope is semiflexible tube that should be manipulated by operator for inspection and treatment. Therefore, it sometimes causes pain for the patient and even perforation to the wall of colon if a surgeon is not well trained. For safe colonoscopy, self-propelling robots with inchworm locomotion are studied. But, inchworm locomotion has some problems in adaptiveness to the variation of colon diameter. In this paper, we propose novel locomotive mechanism which can move in the colon without any external assistance. It has several cams that have constant phase difference each other and located along the centerline of the mechanism. This mechanism could realize the robotic endoscope which has continuous and smooth thrust force.

• 한국산학기술학회논문지
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• 제17권6호
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• pp.521-526
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• 2016

본 논문에서는 환자의 대장 내에서 자율적으로 이동이 가능한 자율주행 형 대장 내시경의 주행 메커니즘으로서 회전관성을 이용하여 환자의 장내 주행이 가능한 새로운 주행메커니즘의 설계 방법에 대해 제안한다. 상업용 대장 내시경은 시술할 때 환자에게 장시간의 고통과 불쾌감을 제공하여 환자들이 시술을 꺼리게 되어 내시경 검사가 필요한 대장 암 등의 조기 진단에 차질을 빚고 있다. 이 문제를 해결하기 위하여 환자의 장관 내에서 자율적으로 이동함으로써 불쾌감이나 고통을 줄일 수 있는 로봇 형 차세대 내시경에 대한 연구가 진행되어 왔다. 회전관성을 이용하는 주행 메커니즘에서는 회전관성을 일으키기 위하여 flywheel을 모터로 구동하여 에너지를 저장한다. flywheel에 의한 에너지 저장과 방출에 의하여 장내에서 로봇이 주행할 때 일어나는 stick-slip 현상을 효율적으로 극복할 수 있다. 이를 위해 flywheel의 속도제어가 가능하고 고주파 노이즈에 강건한 제어기를 설계하고 구현하였다. 여기서 제시하는 회전관성을 이용한 주행 메커니즘은 다른 메커니즘에 비해 구조가 간단할 뿐 아니라 주행도 효율적임을 실험을 통하여 증명하였다.

• 대한기계학회논문집A
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• 제34권6호
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• pp.789-795
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• 2010

본 논문은 자벌레 이동장치의 전, 후반부에 각각 여섯 개의 다리로 이루어진 고정장치를 사용하여 인체 내에서 원활하게 이동할 수 있는 대장내시경로봇을 제안하였다. 또한, 관탐사용 이동장치로 기 개발된 하나의 공압선을 이용한 자벌레 이동방식을 적용하여 공압선과 이동환경 사이의 마찰을 줄여주어 이동 성능을 높여주었다. 이동 성능을 평가하기 위하여 로봇을 직경 15mm, 길이 110~250mm 의 크기로 설계 및 제작 후, 아크릴 관과 죽은 돼지의 창자에서 이동실험을 수행하였다. 실험을 통하여 로봇은 곡관의 반경이 25mm 이상이면 이동이 가능함을 알 수 있었고, 직관의 경우 수평관에서 33mm/s, 수직관에서 12.1mm/s 의 이동 속도를 보여주었다. 결론적으로 하나의 공압선을 이용하여 구동되고 양단에 다리로 구성된 고정장치를 장착한 제안된 로봇은 대장내시경 로봇으로써 신뢰성이 높은 이동성능을 보여주었다.

• Clinical Endoscopy
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• 제55권4호
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• pp.540-548
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• 2022

Background/Aims: Colorectal polyps are removed to prevent progression to colorectal cancer. Polyp size is an important factor for risk stratification of malignant transformation. Endoscopic size estimation correlates poorly with pathological reports and several factors have been suggested to influence size estimation. We aimed to gain insight into the factors influencing endoscopic polyp size estimation. Methods: Images of polyps in an artificial model were obtained at 1, 3, and 5 cm from the colonoscope's tip. Participants were asked to estimate the diameter and volume of each polyp. Results: Fifteen endoscopists from three large-volume centers participated in this study. With an intraclass correlation coefficient of 0.66 (95% confidence interval [CI], 0.62-0.71) for diameter and 0.56 (95% CI, 0.50-0.62) for volume. Polyp size estimated at 3 cm from the colonoscope's tip yielded the best results. A lower distance between the tip and the polyp was associated with a larger estimated polyp size. Conclusions: Correct endoscopic estimation of polyp size remains challenging. This finding can affect size estimation skills and future training programs for endoscopists.