• 전기학회논문지
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• 제63권3호
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• pp.389-394
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• 2014

Two evolutionary gait generation methods for Cartesian and Joint coordinates space are compared to develop a fast locomotion for quadruped robots. GA(Genetic Algorithm) based approaches seek to optimize a pre-selected set of parameters for the locus of paw and initial position in cartesian coordinates space. GP(Genetic Programming) based technique generate few joint trajectories using symbolic regression in joint coordinates space as a form of polynomials. Optimization for two proposed methods are executed using Webots simulation for the quadruped robot which is built by Bioloid. Furthermore, simulation results for two proposed methods are analysed in terms of different coordinate spaces.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1593-1596
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• 1997

Because the leg mechanism of walking roblt affect on the mobility and energy efficiency, we focus on the design of new leg mechanism based on the previous leg mechanisms. We mention the deficiency of the previous leg mechanisms and propose a new leg mechanism that consists of a 2-d.o.f pantograph mechanism and a vertical linear actuator. The pantograph mechanism is attached to the horizontal plane of the body and the verical linear actuator is vertical to that plane. In order to design a quadruped walking robot, we consider the kinematics of the 2-d.o.f pantograph mechanism and the arrangement of twol linear motion guides that drive the pantograph mechanism.

• 제어로봇시스템학회논문지
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• 제15권6호
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• pp.626-633
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• 2009

A motion planning algorithm is presented in this paper for a commercialized quadruped walking of robot pet. Stable walking is the basic requirement for a commercial-purpose legged robot. In order to secure the walking stability, modified body sway to the centroid of support polygon is addressed. By representation of walking motion with respect to the world coordinate system rather than body coordinate, it is possible to design the several gaits in unified fashion. The initial gait posture is introduced to maximize the stride and to achieve fast walking. The proposed walking motion planning is verified through computer simulation and experiments.

• 제어로봇시스템학회논문지
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• 제7권8호
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• pp.675-679
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• 2001

This paper presents walking algorithm for a quadruped robot that does not have an upper body. Tilting motion is added to the planned walking trajectory instead of using an extra body segment that is independent on walking trajectory. Area and tracking algorithms are proposed as tilting method and compared with that of off-line tilting and that of no tilting. Computer simulation shows that stability of tilted walking is more improved than that of the usual walking algorithm for general walking paths. It also shows that the tracking method guarantees stability and best mobility.

• 제어로봇시스템학회논문지
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• 제14권6호
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• pp.573-579
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• 2008

This paper introduces a new approach to develop a fast gait for quadruped robot using GP(genetic programming). Planning gaits for legged robots is a challenging task that requires optimizing parameters in a highly irregular and multidimensional space. Several recent approaches have focused on using GA(genetic algorithm) to generate gait automatically and shown significant improvement over previous results. Most of current GA based approaches used pre-selected parameters, but it is difficult to select the appropriate parameters for the optimization of gait. To overcome these problems, we proposed an efficient approach which optimizes joint angle trajectories using genetic programming. Our GP based method has obtained much better results than GA based approaches for experiments of Sony AIBO ERS-7 in Webots environment.

• 한국정보통신학회논문지
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• 제8권7호
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• pp.1418-1423
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• 2004

관절형 로봇은 바퀴구동로봇에 비해 인간과 비슷한 형태를 갖추고 있어 친화성이 높고 관절로 인하여 자유도가 높으며 접지점을 임의로 설정할 수 있다. 또한 접지위치와 본체와의 상대위치를 자유로이 설정할 수 있으며 관절을 매니플레이터로서 사용할 수도 있는 장점을 가지고 있다. 이에 반해 많은 자유도를 가지고 있어 기구가 복잡하고 이동속도가 바퀴구동로봇에 비해 늦으며 이동시 진동이 일어나기 쉽고 로봇이 넘어지지 않도록 하는 특별한 제어가 필요하게 된다. 많은 생물들의 기본다리인 4족형 구조는 동적안정을 유지하면서 이동을 계속할 수 있고, 또 보행중에도 기구적으로 쓰러짐을 회피할 수 있는 완전보행을 실현하는 최소한의 관절수로 구성되어 있는 보행형태이다. 이러한 보행실험을 위해 4족 보행로봇인 TITAN-VIII을 이용하여 Trot 보행 알고리즘을 연구하여 보행 실험을 행하였다.

• 한국지능시스템학회논문지
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• 제19권6호
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• pp.749-754
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• 2009

4족 보행로봇의 빠른 걸음새를 자동으로 생성하는 문제에 대해서 GP(Genetic Programming)와 CPG(Central Pattern Generator) 기반의 두 가지 방식을 비교한다. GP(Genetic Programming)를 이용한 관절좌표계 상에서의 걸음새 생성 기법은 발끝의 자취와 수 많은 자세 파라미터를 사용하는 대신에 적은수의 관절 궤적을 생성하므로 효율적이다. CPG는 뇌로부터의 입력을 받아서 진동적인 출력을 생성하는 신경회로로 고등생물의 걸음 원리를 수학적으로 모델링한 것이다. 바이올로이드로 구성된 4족 보행로봇에 대하여 Webots기반의 ODE 시뮬레이션을 통해 접근 기법들에 대한 최적화를 수행하고 결과를 비교 분석한다. 그리고, 구해진 시뮬레이션과 결과를 실제 로봇에 대해서 각 동작을 실행시켜 보면서 CPG와 GP 기반의 걸음새 방식의 실제적인 성능 및 특성을 고찰한다.

• 로봇학회논문지
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• 제14권3호
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• pp.196-202
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• 2019

Snake robots are slower than wheeled robots or legged robots, while they have an excellent terrainability in a disastrous area. Considering their advantages and disadvantages, a legged robot whose legs are snake robots, 'Quadnake' was proposed in this research. Five motions of the snake were analyzed. Applying these motions, Quadnake could implement eight kinds of motions which snake robots and quadruped walking robots can implement. As a result of it, Quadnake can have the advantages of both a snake robot and a walking robot. It is expected to move stably in a harsh terrain with snake's motion and move fast with walking.

• 대한전기학회논문지:시스템및제어부문D
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• 제54권9호
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• pp.547-555
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• 2005

A fault-tolerant gait of multi-legged robots with static walking is a gait which can maintain gait stability and continue its walking against an occurrence of a leg failure. This paper proposes fault-tolerant gait planning of a quadruped robot walking over a rough planar terrain. The considered fault is a locked joint failure, which prevents a joint of a leg from moving and makes it locked in a known position. In this Paper, two-phase discontinuous gaits are presented as a new fault-tolerant gait for quadruped robots suffering from a locked joint failure. By comparing with previously developed one-phase discontinuous gaits, it is shown that the proposed gait has great advantages in gait performance such as the stride length and terrain adaptability. Based on the two-phase discontinuous gait, quasi follow-the-leader(FTL) gaits are constructed which enable a quadruped robot to traverse two-dimensional rough terrain after an occurrence of a locked joint failure. During walking, two front legs undergo the foot adjustment procedure for avoiding stepping on forbidden areas. The Proposed wait planning is verified by using computer graphics simulations.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2003년도 ISIS 2003
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• pp.228-231
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• 2003

This paper presents the leg trajectory generation for the quadruped robot with genetic-fuzzy algorithm. To have the nobility even at uneven terrain, a robot is able to recognize obstacles, and generates moving path of body that can avoid obstacles. This robot should have its own avoidance algorithm against obstacles, forwarding to target without collision. During walking period, n robot recognizes obstacle from external environment with a PSD and some interface, and this obstacle information is converted into proper the body rotation angle by fuzzy inference engine. After this process, we can infer the walking direction and walking distance of body, and finally can generate the optimal Beg trajectory using genetic algorithm. All these methods are verified with PC simulation program, and implemented to SERO-V robot.