• Journal of Mechanical Science and Technology
• /
• v.20 no.7
• /
• pp.1012-1018
• /
• 2006

Diagnosis and treatment using the conventional flexible endoscope in gastro-intestinal tract are very common since advanced and instrumented endoscopes allow diagnosis and treatment by introducing the human body through natural orifices. However, the operation of endoscope is very labor intensive work and gives patients some pains. As an alternative, therefore, the capsule endoscope is developed for the diagnosis of digestive organs. Although the capsule endoscope has conveniences for diagnosis, it is passively moved by the peristaltic waves of gastro-intestinal tract and thus has some limitations for doctor to get the image of the organ and to diagnose more thoroughly. As a solution of these problems, various locomotive mechanisms for capsule endoscopes are introduced. In our proposed mechanism, the capsule-type microrobot has synchronized multiple legs that are actuated by a linear actuator and two mobile cylinders inside of the capsule. For the feasibility test of the proposed microrobot, a series of in-vitro experiments using small intestine without incision were carried out. From the experimental results, our proposed microrobot can advance along the 3D curved and sloped path with the velocity of about $3.29\sim6.26mm/sec$ and $35.1\sim66.7%$ of theoretical velocity. Finally, the proposed locomotive mechanism can be not only applicable to micro capsule endoscopes but also effective to advance inside of gastro-intestinal tract.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.30 no.3 s.246
• /
• pp.287-294
• /
• 2006

In recent years, capsule endoscope is highlighted for the patient's convenience and the possibility of the application in the small intestine. However, the capsule endoscope has some limitations to get the image of the digestive organ because its movement only depends on the peristaltic motion. In order to solve these problems, locomotion of capsule endoscope is necessary. In this paper, we analyze the locomotive mechanism of earthworm-like robot proposed as locomotive device of capsule endoscope and derive the condition which can Judge the possibility of its mobility using theoretical analysis. Based on a biomechanical modeling and simulation, the critical stroke, that is minimum stroke of the earthworm-like robot to perform motion inside small intestine, is obtained. Also, this derived critical stroke can be validated by the moving test of fabricated earthworm-like robot. Consequently, it is expected that this study can supply useful information to design of earthworm-like robot for mobility of capsule endoscope.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.37 no.4C
• /
• pp.329-337
• /
• 2012

Capsule Endoscope(CE) is a capsule-shaped electronic device which can examine the lesions in digestive tract of human body. Recently the medical procedure using capsule endoscope is receiving great attention to both doctors and patients, since the conventional push-typed endoscope using cables brings great pain and fear to the patients. The technique was firstly available in 2000 and is based on a convergence techniques among BT(Bio Technology), IT(Information Technology), and NT(Nano Technology). The device consists of an optical parts including LEDs(Light Emitting Diodes), an image sensor, a communication module and a power module. Capsule endoscope is the embodiment of the state-of-the art technology and requires key technologies in the various engineering fields. Therefore, in this paper, we introduce the composition of the capsule endoscope system, and compare the communication method between RF(Radio Frequency) communication and HBC(Human Body Communication), which are typically used for data transmission in the capsule endoscope. Furthermore, we analyze the specification of commercialized capsule endoscopes and present the future developments and technical challenges.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.06a
• /
• pp.1068-1073
• /
• 2005

Development of a locomotive mechanism for the capsule type endoscopes will largely enhance the ability to diagnose disease of digestive organs. In connection with it, most of the researches have focused on an installable locomotive mechanism in the capsule. In this paper, it is introduced that the movement of a capsule type endoscope in digestive organ can be manipulated by magnetic force produced outside human body. Since the magnetic force is provided by permanent magnets, no additional power supply to the capsule is required. Using a robotic manipulator for locating the external magnet, the capsule motion control system can cover the whole human digestive organs. This study is particularly concentrated on dither motion effect to improve the mobility of capsule type endoscope. It was experimentally found out that the friction coefficient between the capsule and digestive organ can be remarkably reduced by superposing yawing or rolling dither motion on the translatory motion. In this paper, the experimental results obtained while the direction, amplitude and frequency of sinusoidal dither motion were changed are reported.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 2002.10b
• /
• pp.367-368
• /
• 2002

The design of capsule body for self-propelled endoscope is important from the frictional resistance point of view. The capsule should be able to overcome the frictional resistance in order to move along the intestine. The motivation of this work was to gain a better understanding of the capsule body design on the frictional resistance of the capsule inside an intestine. A special experimental set-up was built to measure the frictional resistance as the capsule was being pulled inside the pig intestine specimen. Tests were performed with open and closed intestine specimens. Experimental data showed that smooth cylindrical capsule geometry resulted in the least frictional resistance. The resistance inside the closed intestine specimen was about four times higher than that of the open specimen. It is expected that the results of this work will be used to design the optimum propulsion system for the microendoscope.

• Journal of the Korean Society for Precision Engineering
• /
• v.22 no.8 s.173
• /
• pp.57-63
• /
• 2005

Development of a locomotive mechanism fer the capsule type endoscopes will largely enhance the ability to diagnose disease of digestive organs. In connection with it, most of researches have focused on an installable locomotive mechanism in the capsule. In this paper, it is introduced that the movement of a capsule type endoscope in digestive organ can be manipulated by magnetic force produced outside human body. Since the magnetic force is provided by permanent magnets, no additional power supply to the capsule is required. Using a robotic manipulator for locating the external magnet, the capsule motion control system can cover the whole human digestive organs. This study is particularly concentrated on dither motion effect to improve the mobility of capsule type endoscope. It was experimentally found out that the friction coefficient between the capsule and digestive organ can be remarkably reduced by superposing yawing or rolling dither motion on the translatory motion. In this paper, the experimental results obtained with the direction, amplitude and frequency of sinusoidal dither motion changed is reported.

• Journal of the Korean Society for Precision Engineering
• /
• v.24 no.6
• /
• pp.66-71
• /
• 2007

Development of a locomotive mechanism for the capsule type endoscopes will largely enhance their ability to diagnose disease of digestive organs. As a part of it, there should be provided a detection device of their position in human organs for the purpose of observation and motion control. In this paper, a permanent magnet outside human body was employed to project magnetic field on a capsule type endoscope, while its position dependent flux density was measured by three hall-effect sensors which were orthogonally installed inside the capsule. In order to detect the 2-D position data of the capsule with three hall-effect sensors including the roll, pitch and yaw angle, the permanent magnet was extra translated during the measurement. In this way, the 2-D coordinates and three rotation angles of a capsule endoscope on the same motion plane with the permanent magnet could be detected. The working principle and performance test results of the capsule position detection device were introduced in this paper showing that they could be also applied to 6-DOF position detection.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.30 no.1 s.244
• /
• pp.84-89
• /
• 2006

A wireless capsule endoscope has been developed to replace the conventional endoscope. However, the commercialized capsule endoscope moves passively by peristaltic waves, which has some limitations for doctors to diagnose more thoroughly and actively. In order to solve this problem, a locomotive mechanism is proposed for wireless capsule endoscopes. Based on the tests of various actuators, a piezo actuator is selected as a micro actuator for capsule endoscope. In general, piezo actuators are known to have limited displacement with high voltage supply. In order to overcome the limitation of common piezo actuator, the impact based piezo actuator, is developed to realize long stroke up 11mm. By using the impact based piezo actuator, a prototype of an earthworm-like locomotive mechanism was developed. In addition, the proposed locomotive mechanism has engraved clamps mimicked the claw of an insect. The earthworm-like locomotive mechanism has 15 mm in diameter and 30mm under retraction stage and 41 mm under elongation stage in total length. Hollow space is allocated to comprise essential endoscope components such as a camera, a communication module, bio sensors, and a battery. For the feasibility test of proposed locomotive mechanism, a series of experiments were carried out including in-vitro tests. Based on results of the experiments, we conclude that the proposed locomotive mechanism is effective to be used for micro capsule endoscopes.

• Journal of Biomedical Engineering Research
• /
• v.43 no.6
• /
• pp.417-423
• /
• 2022

The present study proposed a new interface system for capsule endoscopy by using head mounted display (HMD) device, which can control the orientation of the capsule endoscope with electromagnetic actuator (EMA) system. The orientation information of the HMD user was detected by the gyroscope sensor built into the device and then calculated to as an angle increment using Unity Engine compiler. The measured angle changes from the HMD were converted to the current values of the corresponding coils to be changed in the EMA system. Two experiments were designed to measure the accuracy and the intuitiveness of the HMD interface system. In the angle accuracy measurement, the capsule endoscope driven by HMD interface system showed the averaged errors of 0.68 degrees horizontally and 1.001 degrees vertically for given test angles. In the intuitiveness measurement, HMD interface system showed 1.33 times faster manipulation speed rather than the joystick interface system. In this respect, the HMD interface system for capsule endoscopy was expected to improve the overall diagnostic environment while maintaining comfort of patients and clinicians.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2002.05a
• /
• pp.142-145
• /
• 2002

In order to develop a self-propelled microendoscope, the frictional resistance of the capsule-type endoscope inside the intestine should be understood. In this work the frictional resistance behaviors of capsules with different designs were experimentally investigated using a pig intestine. It was found that cylindrical capsule design had the least frictional resistance. Also, the resistance increased as the speed of the capsule motion was decreased. It is expected that the results of this work will be used to design the optimum propulsion system for the microendoscope.