• 전기학회논문지
• /
• 제67권7호
• /
• pp.903-909
• /
• 2018

We propose laser scanner sensor system based walking pattern and tracking method of multiple human. This system uses laser scanners sensors and is applicable to wide and crowded area such as hospital and medical care center. The primary objective of this research is to promote the development of robust, repeatable and transferable software for security system that can automatically detect, track and follow people in public area. We developed the method of human identification for this system. Our method is following: 1. Best-walking pattern data are obtained by the help of human position and direction data obtained by laser scanners. 2. Human identification is conducted by calculating the correlation between the step length of walking human. It becomes possible to conduct human identification even in crowded scenes by estimating the movements of waling human' feet are periodic. In the experiment in the station, some effectiveness of this method became clear.

• 한국정밀공학회지
• /
• 제24권2호
• /
• pp.86-94
• /
• 2007

In this paper, a dual stage servo mechanism has been developed for image tracking system to improve control performances such as small rise time, small overshoot, small settling time, small stabilization error etc. A secondary stage, a platform, actuated by a pair of electro-magnets is mounted on a conventional elevation gimbal. In this mechanism, the gimbal provides large range but slow motion and the platform provides small range but fast positioning. A sliding mode control is applied to the platform positioning to attain robust performances and stability in the presence of the disturbance related to dynamic coupling of the gimbal and the platform. Results from experiments illustrate that the suggested dual stage mechanism controlled by the sliding mode control is effective in improving responses and attenuating the disturbance response related with dynamic coupling.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2002년도 춘계학술대회 논문집
• /
• pp.357-360
• /
• 2002

Nowadays, the improvement and development of Multi-media, information and communication technology are rapidly processed. And many products, for example, digital camera, digital camcorder, and PDA, are used for them. They need large data storage capacity and small size, light storage system. Due to that, many studies and researches in data storage system have been carried out. Especially, micro drive system was presented by IBM.(1) However, its system is expensive and uneasy to be portable. In ODD technologies, 1 inch drive system is not yet or in processing status.(2) If to be possible and to be come up, it is cheap than HDD system and easy to transfer information. In this paper, a miniaturized actuator(about linch) is designed and tested for ODD system. Specially, it is adapted for NFR(Near-field Recoding) system using SIL(Solid Immersion Lens). It is the dual-servo actuator which consists of a coarse actuator and fine actuator. Its actuating force generation method is VCM(Voice Ceil Motor). The fine actuator has 4-wire suspensions and bobbin wrapped by coil and includes focusing motion as well as tracking motion. The coarse actuator has an actuating coil and V-grooved guide mechanism. Also, the characteristics of the designed actuator is estimated by sine-swept mode and LDV(Laser Doppler Vibro-meter).

• 한국의학물리학회지:의학물리
• /
• 제28권3호
• /
• pp.92-99
• /
• 2017

In respiratory-induced proton therapy, the accuracy of tracking system and beam controlling is more important than photon therapy. Therefore, a high accuracy motion tracking system that can track internal marker and external surrogate is needed. In this research, our team has installed internal and external marker tracking system at our institution's proton therapy system, and tested the scanning with gating according to the position of marker. The results demonstrate that the developed in-house external/internal marker based gating system can be clinically used for proton therapy system for moving tumor treatment.

• 한국정밀공학회지
• /
• 제16권5호통권98호
• /
• pp.58-65
• /
• 1999

A magnetic levitation system requires a robustness to overcome a dynamic instability due to disturbances. In this paper a robust controller for a magnetically levitated fine manipulator is presented. The proposed controller consists of following two parts: a model reference controller and an $H_{\infty}$ controller. First, the model reference control stabilizes the motion of the manipulator. Then, the motion of the manipulator follows that of the reference model. Second, the $H_{\infty}$ control minimizes errors generated from the model reference control due to noise and disturbance since the $H_{\infty}$ control is a kind of robust control. The experiments of position control and tracking control are carried out by use of the proposed controller under the conditions of free disturbances and forced disturbances. Also, the experiments using PID controller are carried out under the same conditions. The results from above two controllers are compared to investigate the control performances. As the results, it is observed that the proposed controller has similar position accuracy but better tracking performances comparing to the PID controller as well as good disturbance rejection effect due to the robust characteristics of the controller. In conclusion. it is verified that the proposed controller has the simple control structure, the good tracking performances and good disturbance rejection effect due to the robust characteristics of the controller.

• 한국의학물리학회지:의학물리
• /
• 제20권3호
• /
• pp.174-179
• /
• 2009

사이버나이프 로봇 방사선 수술 시스템은 환자를 치료하는 동안 환자의 내부 기준 마커를 이용하여 종양의 위치를 실시간으로 추적 할 수 있는 시스템이다. 최근 폐종양 치료의 경우 기준 마커의 삽입 없이 폐종양의 밀도 차이를 이용하여 실시간 종양 추적을 할 수 있는 폐종양추적시스템이 개발되어 치료에 적용되고 있다. 최근 개발되어 국내 최초 도입된 폐종양 추적치료시스템의 위치 추적 정확도의 분석은 동적흉부 팬톰과 GafChromic film을 이용하였다. 폐종양추적시스템을 이용하여 종양의 위치 추적 정확도는 평균 오차 $0.85{\pm}0.22$ mm로 분석되었다. 기준마커 삽입 없이 폐종양추적시스템을 이용하여 폐종양 치료에 매우 유용한 것으로 판단되었다.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2001년도 춘계학술대회논문집B
• /
• pp.146-151
• /
• 2001

The Grand-Touring is a game motion simulator that simulates the race-car driving motion with three hydraulic cylinders which connect the platform and base in parallel. Its motion control system consists of the PC-based main controller and micro-controller based sub-controller. The former one process the dynamic image of race-car in response to the driver's action and computes the reference command for each cylinder and the latter one is designed for the tracking control of hydraulic cylinder and interfacing the auxiliary signals between various sensors/actuator and main controller. In this research, we developed the sub-controller that implements the required functions of Grand-Touring and prove the overall performance with experiments.

• 한국의학물리학회지:의학물리
• /
• 제27권3호
• /
• pp.117-124
• /
• 2016

Intrafractional motion of patients, such as respiratory motion during radiation treatment, is an important issue in image-guided radiotherapy. The accuracy of the radiation treatment decreases as the motion range increases. We developed a control system for a robotic patient immobilization system that enables to reduce the range of tumor motion by compensating the tumor motion. Fusion technology, combining robotics and mechatronics, was developed and applied in this study. First, a small-sized prototype was established for use with an industrial miniature robot. The patient immobilization system consisted of an optical tracking system, a robotic couch, a robot controller, and a control program for managing the system components. A multi speed and position control mechanism with three degrees of freedom was designed. The parameters for operating the control system, such as the coordinate transformation parameters and calibration parameters, were measured and evaluated for a prototype device. After developing the control system using the prototype device, a feasibility test on a full-scale patient immobilization system was performed, using a large industrial robot and couch. The performances of both the prototype device and the realistic device were evaluated using a respiratory motion phantom, for several patterns of respiratory motion. For all patterns of motion, the root mean squared error of the corresponding detected motion trajectories were reduced by more than 40%. The proposed system improves the accuracy of the radiation dose delivered to the target and reduces the unwanted irradiation of normal tissue.

• International Journal of Aeronautical and Space Sciences
• /
• 제10권2호
• /
• pp.86-94
• /
• 2009

This paper deals with the creation of a new, low-cost point/position tracking system that can measure deformations in engineering structures with simple commercially widespread cameras. Though point tracking systems do exist today, such as Stereo Pattern Recognition (SPR) and Projection Moir$\acute{e}$ Interferometry (PMI) systems, they are far too costly to use to analyze small, simple structures because complex optical components such as large flashes, high-resolution cameras and data acquisition systems with several computers are required. We developed a point tracking system using commercial cameras. This system used IR LEDs and commercial IR CCD cameras to minimize the interference posed by other extraneous light sources. The main algorithm used for this system is an optical point tracking algorithm, which is composed of the point extraction algorithm and the point matching algorithm for 3-D motion estimation. a series of verification tests were performed. Then, the developed point tracking system was applied to measure deformations of an acrylic plate under a mechanical load. The measured deformations of the acrylic plate matched well with the numerical analysis results. The results indicate that the developed point tracking system is reliable enough to measure continuous deformed shapes of various engineering structures.

• 한국해양공학회지
• /
• 제37권4호
• /
• pp.158-163
• /
• 2023

Objects adrift can cause considerable damage to coastal infrastructure and property during tsunami and storm surge events. Despite the potential for harm, the drifting behavior of these objects remains poorly understood, thereby hindering effective prediction and mitigation of collision damage. To address this gap, this study employed a motion analysis program to track a drifting container's location using images from an existing laboratory experiment. The container's trajectory and velocity were calculated based on the positions of five markers strategically placed at its four corners and center. Our findings indicate that the container's maximum drift velocity and distance are directly influenced by the scale of the solitary wave and inversely related to the container's weight. Specifically, heavier containers are less likely to be displaced by solitary waves, while larger waves can damage coastal structures more. This study offers new insights into container drift behavior induced by solitary waves, with implications for enhancing coastal infrastructure design and devising mitigation strategies to minimize the risk of collision damage.