• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.225-230
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• 2003

This paper proposes a desired trajectory and a control algorithm for a biped robot with curved soles. Firstly, we derived the desired trajectory from a model called the Moving Inverted Pendulum Mode (MIPM) of which a contact point of the foot is moving in the horizontal direction. A biped robot with curved soles is under-actuated system, because it has one contact point with the ground during the single supporting phase. Therefore, to solve the under-actuated problem, we changed control variables, used modified dynamic equations and used the computed torque control. The simulation results show that a biped robot with curved soles walks stably. Also, fast walking and natural motion of a biped robot can be implemented.

• Journal of Mechanical Science and Technology
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• 제20권5호
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• pp.602-611
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• 2006

This paper proposes a locomotion pattern and a control method for biped robots with curved soles. First, since the contact point of a supporting leg may arbitrarily move back and forth on the ground, we derived the desired trajectory from a model called the Moving. Inverted Pendulum Model (MIPM) where the Zero Moment Point (ZMP) exists at the supporting point and can be moved intentionally. Secondly, a biped robot with curved soles is an under-actuated system since the supporting point contacting with a point on the ground has no actuator during the single supporting phase. Therefore, this paper proposes a computed-torque control for this under-actuated system using decoupled dynamic equations. A series of computer simulations with a 7-DOF biped robot with curved soles shows that the proposed walking pattern and control method are effective and allow the biped robot to walk fast and stably, and move more like human beings. Also, it is shown that the curved sole shape has superior energy consumption compared to flat soles, and greater efficiency in ascending and descending the stairs.

• The Korean Journal of Pain
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• 제13권2호
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• pp.196-201
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• 2000

Background: Currently, minimally invasive operations are preferred to open surgery whenever possible. Lumbar sympathectomy using RF (radiofrequency) thermocoagulation is both safe and minimally invasive. The problem with the technique is that it cannot be performed successfully in a significant number of cases. If the temperature change in the sole is monitored immediately after the procedure then it can be determined if the procedure needs to be repeated. Methods: A curved tip cannula, 150 mm long with a 10 mm active tip, was used for RF lumbar sympathectomy. The temperature of the soles of both the foot on the affected side and the foot on the control side was monitored immediately before the procedure, immediately after making the L2 lesion, immediately after making the L3 lesion and at 5, 10, and 15 minutes after the procedure. Results: No statistically significant difference was observed in the temperature of the two soles before making the lesions. In the 24 of the 27 patients, there were prominent differences in temperature between the two soles at 10 minutes after the procedures. 11 of the 24 patients showed a significant temperature change after the first trial. But the remaining 13 required a second lesion on L2 and L3. Conclusions: We judged the success of the operation in the operating room by monitoring the temperature difference in the soles of the feet. When no increase in the temperature difference is observed, we can move the electrode and make another lesion. With this procedure, we can drastically increase the success rate of the procedure.

• 대한기계학회논문집A
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• 제36권8호
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• pp.913-920
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• 2012

단층촬영 영상정보를 이용하여 근육, 연부조직 및 골 구조 등을 포함한 발의 상세한 유한요소해석모델을 개발하여 보행과정을 모사하였고, 발과 직접 접촉하는 신발밑창 형상의 고려 여부에 따른 보행 중의 발바닥 압력의 변화를 비선형 접촉해석으로 계산하였다. 해석결과 직립 정지상태나 보행 중에는 공통으로 뒤꿈치가 지면에 닿을 때 압력집중이 가장 높았으며, 편평한 밑창보다 발바닥 곡면과 같은 밑창을 사용한 보행해석에서 뒤꿈치의 압력집중이 덜하고 접촉면이 더 넓었다. 이러한 보행모델 및 해석은 발바닥의 압력집중에 취약한 당뇨병 환자 전용 의료보조신발(압력을 넓게 분포시켜 집중의 강도를 낮출 수 있는) 개발의 수단으로 활용될 수 있음을 보였다.

• 한국운동역학회지
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• 제21권1호
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• pp.67-75
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• 2011

The purpose of this study was to find the difference in gait patterns when elderly and young people walk by analyzing COP, Gait Line, Foot pressure pattern, and ensuring the original biomechanics technology of developing high performance footwear for the elderly. The subjects who took part in the test consist of 20 elderly people and 20 young people. The physical features of the elderly people that were recruited for the study are as below: 20 healthy male subjects(elderly people) with an average age of 75.43 yrs(S.D 6.46 yrs), weight of 68.10 kg(S.D 0.94 kg) and a height of 168.65 cm(S.D 1.47 cm). Foot pressure pattern data was collected using a EMED-AT system(Novel Gmbh, Germany) operating at the 50 Hz during walking. The results are as follow : COP route of the elderly leans to lateral compared to the young, and Gait Line from heel to toe is not clear and laterally curved. At the same time, a contact are aonthe midfoot is high compared to the young, and maximum force of the forefoot is low. As a result of analysis, in order to develop high performance footwear for the elderly, it is necessary to develop lasts and soles reflecting the elderly's gait patterns.