유전자 알고리즘을 이용한 새로운 무릎 보장구의 최적 설계

다국어 초록 (Multilingual Abstract)

The objective of this paper is to optimize the design parameters of a novel mechanism for a robotic knee orthosis. The feature of the proposed knee othosis is to drive a knee joint with independent actuation during swing and stance phases, which can allow an actuator with fast rotation to control swing motions and an actuator with high torque to control stance motions, respectively. The quadriceps device operates in five-bar links with 2-DOF motions during swing phase and is changed to six-bar links during stance phase by the contact motion to the patella device. The hamstring device operates in a slider-crank mechanism for entire gait cycle. The suggested kinematic model will allow a robotic knee orthosis to use compact and light actuators with full support during walking. However, the proposed orthosis must use additional linkages than a simple four-bar mechanism. To maximize the benefit of reducing the actuators power by using the developed kinematic design, it is necessary to minimize total weight of the device, while keeping necessary actuator performances of torques and angular velocities for support. In this paper, we use a SGA (Simple Genetic Algorithm) to minimize sum of total link lengths and motor power by reducing the weight of the novel knee orthosis. To find feasible parameters, kinematic constraints of the hamstring and quadriceps mechanisms have been applied to the algorithm. The proposed optimization scheme could reduce sum of total link lengths to half of the initial value. The proposed optimization scheme can be applied to reduce total weight of general multi-linkages while keeping necessary actuator specifications.

목차 (Table of Contents)

• Abstract
• Ⅰ. 서론
• Ⅱ. 설계된 외골격 로봇의 기구
• Ⅲ. 최적화 알고리즘
• Ⅳ. 최적설계 결과
• Ⅴ. 결론
• 참고문헌

참고문헌 (Reference)

1 표상훈, "회전기 및 착지기 분리 구동을 가능케 하는 새로운 무릎 보장구의 기구부 설계" 제어·로봇·시스템학회 17 (17): 814-823, 2011

2 윤정원, "유전 알고리즘을 이용한 6자유도 병렬기구의 최적화 설계" 제어·로봇·시스템학회 13 (13): 560-567, 2007

3 J. S. Sulzer, "adaptation to flexion torque during gait" 23-26, 2009

4 G. Colombo, "Treadmill training of paraplegic patients using a robotic orthosis" 37 (37): 693-700, 2000

5 J. E. Pratt, "The RoboKnee: An exoskeleton for enhancing strength and endurance during walking" 2430-2435, 2004

6 H. Mehdigholi, "Optimization of Watt’s sixbar linkage to generate straight and parallel leg motion" 1 (1): 11-16, 2008

7 P. S. Shiakolas, "On the optimum synthesis of six-bar linkages using differential evolution and the geometric centroid of precision positions technique" 40 : 319-335, 2004

8 D. Jin, "Kinematic and dynamic performance of prosthetic knee joint using six-bar mechanism" 40 (40): 39-48, 2003

9 S. K. Banala, "Gait rehabilitation with an active leg orthosis" 459-465, 2005

10 M. Ackermann, "Automatic knee flexion in lower limb orthosis" 31 (31): 305-311, 2009

11 M.Mitchell, "An introduction to genetic algorithm" Massachusetts Institute of Technology 1996

12 J. H. Holland, "Adaptation in natural and artificial systems" The University of Michigan Press 1975