• 한국운동역학회지
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• 제15권1호
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• pp.75-89
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• 2005

D. K. LEE, J. S. LEE, B. J. LEE, H. S. LEE, Y. J. KIM, S. B. PARK, J. P. JOO. Plantar foot pressure analysis during golf swing motion using plantar foot pressure measurement system. Korean Journal of Sport Biomechanics, Vol. 15, No. 1, pp. 75-89, 2005. In this study, weight carrying pattern analysis and comparison method of four foot region were suggested. We used three types of club(driver, iron7, pitching wedge). This analysis method can compare between top class golfer and beginner. And the comparison data can be used to correct the swing pose of trainee. If motion analysis system, which can measure the swing speed and instantaneous acceleration at the point of hitting a ball, is combined with this plantar foot force analysis method, new design development of golf shoes to increase comfort and ball flight distance will be available. 1. Address acting, forces concentrated in rare foot regions and lateral foot of right foot. Back swing top acting, relatively high force occurred in medial forefoot region of left foot and forefoot region of right foot. Impact acting, high force value observed in the lateral rarefoot region of left foot and medial forefoot region of right foot. Finish acting, force concentration observed on the lateral region and rarefoot region of left foot. 2. Forces were increased in address of right foot with clubs length increased. All clubs, back swing top acting, high force value observed in the lateral forefoot region of right foot. All clubs, in impact, high force value observed in the lateral rarefoot region of left foot and medial forefoot region of right foot. Finish acting, force concentration observed on the rarefoot region in driver and lateral foot region in iron on left foot. 3. Right foot forces distribution were increased in address, back swing top and left foot force distribution were increased in impact, finnish

• 한국운동역학회지
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• 제19권1호
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• pp.167-177
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• 2009

본 연구의 목적은 골프화 개발에 있어 골프화 종류에 따른 기능성 검증을 위해 골프 스윙 시 골프화 종류별 3차원 동작분석을 통하여 골프화가 골프 스윙에 미치는 영향을 알아보고자 한다. 연구대상은 골프 프로 자격증을 소지한 경력 10년 이상인 프로골퍼 5명으로 착용 골프화 사이즈가 270mm이었다. 스윙 동작 분석을 위해 Motion Analysis사(Santa Rosa CL USA)의 3차원 동작분석 시스템 및 EVaRT 4.2 소프트웨어를 사용하여 변인 값들을 분석하였다. 드라이버 스윙동작 중 어드레스(El), 탑(E2), 임팩트(E3), 피니쉬(E4)시의 각 이벤트 간의 구간(P1, P2, P3) 변인 값을 분석하여 스윙 구간별 시간, 최대속도, 신체이동 속도, 양발 분절의 속도, 발목의 뒤틀림 각도에 대한 조사를 실시하여 골프화의 종류와 수행능력의 연관성에 대하여 알아보았다. 실험결과 골프화 Type C의 경우 어드레스에서 탑까지의 시간이 가장 짧게 나타나 어드레스 시 안정성을 향상시켜 줄 것으로 사료된다. 또한 좌우 골프화의 최대 속도 신체중심 이동 최대 속도 좌우 발의 최대 속도의 경우도 골프화 Type C의 속도가 가장 빠르게 나타났으며 신체의 중심을 빠르게 하고 발의 회전력을 증가시켜 임팩트 시 다른 골프화보다 큰 힘을 전달할 수 있을 것으로 사료된다.

• 제어로봇시스템학회논문지
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• 제18권7호
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• pp.688-698
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• 2012

This paper deals with ROLSO (Reduced Order Luenberger State Observer) design to prevent jackknifing phenomenon of articulated vehicles consisting of the tractor and semi-trailer by using GPS. In addition, by applying the regulator system using ROLSO feedback system, simulation's result presents that articulated vehicle's states are stabilized than the human's PR time (Preception Response time) rapidly. This simulation verifies that the automatic control of articulated vehicle's can be applied for the accident prevention for the time that the driver is unable to manage with the sudden accident. For this simulation, by using the equation of planar motion, the modeling of the articulated vehicle was performed. This modeling was expressed in the state space model. And FOLSO (Full Order Luenberger State Observer), ROLSO were designed by using the state space model of an articulated vehicle's dynamics.

• Journal of Advanced Marine Engineering and Technology
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• 제38권1호
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• pp.39-47
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• 2014

본 연구에서는, 자동으로 조작되는 밸브의 제어기로 사용되는 유압모션 제어기의 한계점인 설정치 추종성능과 외란 억제성능을 개선하기 위한 방법으로 기존의 PID 제어기에 피드-포워드 제어기를 추가한 2자유도(DOF) PID 제어기를 이용하였다. 이 제어기의 제어인자(Parameter)를 최적화시키는 도구로 실수코딩 유전알고리즘(Real Coded Genetic Algorithm, RCGA)을 이용하고 시뮬레이션을 통해 제어기의 성능을 검증하였다.

• 한국전문물리치료학회지
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• 제21권1호
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• pp.55-62
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• 2014

For professional drivers, there is a possibility to have musculoskeletal disorders on ankle joint due to repetitive pedaling operation. Therefore, this study have focused to examine ankle active range of motion (AROM), dorsiflexor strength, and pressure pain threshold (PPT) of tibialis anterior muscle (TA) in taxi drivers compared to a age-matched control group. Thirty male taxi drivers with at least 10 years of driving experience and thirty male sedentary workers were evaluated for ankle AROM, dorsiflexor strength, and PPT of TA. Multiple independent t-tests were used to identify significant differences between two groups. For the results, taxi drivers had significantly less AROM in dorsiflexion and greater AROM in external tibial rotation compared to the control group. Also, dorsiflexor strength and PPT of TA in taxi drivers was significantly lower than in the control group. This study indicates that the repetitive ankle movements associated with driving have an effect on ankle AROM, dorsiflexor strength, and PPT of TA and may lead to work-related musculoskeletal disorders on ankle. Professional drivers may need to be educated to prevent a potential musculoskeletal disorders associated with repetitive movement.

• 전기학회논문지
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• 제59권3호
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• pp.645-650
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• 2010

In this paper we present the Bimodal-tram simulator using the PXI embedded real-time controllers. The Bimodal-tram is developed in KRRI (Korea Railroad Research Institute). The vehicle can be automatically operated by navigation control system (NCS). For the automatic driving, the vehicle lanes will be marked with permanent magnets that are placed in the ground. The vehicle is controlled by NCS. NCS governs the manual mode and automatic mode driving. The simulator is designed by an identical conception with the real control condition. The dynamic motion of vehicle is simulated by the nonlinear dynamic model. The control computer calculates the control values. The signal interface is linked by CAN communication. The simulation is processed by real-time base. The test driver can see the graphic motion of vehicle and can operate the steering wheel, gas and brake pedal to control direction and velocity of vehicle during the simulation. At present, the simulator is only operated by manual mode. The automatic mode will be linked after the control algorithm is finished. We will use the simulator to develop the control algorithm in the automatic mode. This paper shows the simulator designed for Bimodal-tram using real-time based controller. The results of the test using the simulator are presented and discussed.

• 한국정밀공학회지
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• 제19권8호
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• pp.47-54
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• 2002

A barrel cam is used as a very important part of an index drive unit. The index drive unit must have an intermittent-rotational motion. The barrel typed cam and roller gear mechanism has the advantages of high reliability to perform a prescribed motion of a follower. This paper proposes a new method for the shape design of the barrel cam and also a CAD program is developed by using the proposed method. As defined in this paper, the relative velocity method for the shape design calculates the relative velocity of the follower versus cam at a center of roller, and then determines a contact point by using the geometric relationships and the kinematic constraints, where the direction of the relative velocity must be parallel to a common tangential line at the contact point of two independent bodies, i.e. the cam and the follower Then, the shape of the cam is defined by the coordinate transformation of the trace of the contact points. This paper presents two examples for the shape design of the barrel cam in order to prove the accuracy of the proposed methods.

• 한국자동차공학회논문집
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• 제21권6호
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• pp.195-200
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• 2013

Road loads data are indispensable in the evaluation of BSR (Buzz, Squeak, and Rattle) of automotive parts/modules. However, there are uncertainties on the best measurement locations for representative body motion and for seat systems. In the present study, we measure road loads at four different locations of a body. A-pillars on the driver and passenger sides and left and right frame fronts of the front passenger seat mountings are selected to study the acceleration behavior at different locations. The measurements are conducted with passenger cars driving local roads at 50km/hr. The measured time-acceleration data are then transformed into PSD (power spectral density) data to compare the characteristics of local accelerations. By defining the deviated acceleration components from rigid body motion, the stiffness of vehicle body could be simply expressed in a quantitative basis. Measured data from two different vehicles are presented to demonstrate their relative vehicle body stiffness.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2008년도 하계학술대회 논문집
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• pp.553-555
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• 2008

현재 사용하고 있는 LCD(Liquid Crystal Display) Backlight용 램프는 주로 CCFL(Cold Cathod Fluorescent Lamp)과 EEFL(External Electrode Fluorescent Lamp)이 사용되고 있다. 하지만 이 램프는 수은을 사용하여 RoHS(the Restriction of the use of certain Hazardous Substances in electrical and electronic equipment)규제가 점점 강화되면서 사용이 제한되고 있으며, 이에 따라 수은을 사용하지 않는 램프의 제작이 불가피해지고 있다. 또한 LCD TV는 CRT와 PDP와는 다른 LCD만의 Hold-type 특성과 LC(Liquid Crystal)의 응답속도로 인하여 Motion Blur현상이 나타나는 단점이 있다. 본 논문에서는 RoHS 규제를 만족시키는 무수은 면광원 램프를 구동하기 위한 인버터를 제안한다. 제안한 인버터는 포워드 방식을 사용하여 반도체 소자 및 자기 소자의 수를 줄여서 구동회로가 간단하다. 또한 면광원 램프를 세로방향으로 6블록으로 나누어 스캔구동을 하여 Motion Blur현상을 저감 시켰다. 끝으로 실험을 통하여 제안한 인버터의 유용성을 입증하였다.

• 대한인간공학회지
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• 제24권4호
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• pp.55-62
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• 2005

This study examined the effect of ergonomic heel rest that was designed for drivers who have physical handicap in the low leg muscles or have to drive prolonged hours with frequent foot pedaling. An experiment was designed to test the ergonomic heel rest with traditional foot pedal. Forty subjects participated in the experiment. Electromyography(EMG) was used to monitor the muscle activity and fatigue of right leg, and Electro-goniometer was used to measure the ranges of motions of the knee and ankle. A simulator of driver's seat was built for the experiment and the heel rest was installed on it. In order to examine the low muscle activity and range of motion, subjects used the foot pedal for 15 minutes repetitively for each experimental condition. Another 15 minutes test without the heel rest was also performed for comparison. The Root Mean Square(RMS) and Mean Power Frequency(MPF) Shift were used to quantify the level of muscle activity and local muscle fatigue. In results, statistically significant decreases of muscle activity and fatigue were found in all the low leg muscles. The range of motion of the knee and ankle joint also decreased when the heel rest was used. The mechanism of the heel rest effect was discussed in this study. This type of heel rest can be applied to real driving situation after ensuring the safety, or overcoming the psychological discomfort possibly due to unfamiliarity.