• 대한기계학회논문집A
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• 제24권4호
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• pp.1007-1015
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• 2000

This paper proposes an adaptive trajectory generation strategy of using on-line ZMP information and an impedance control method for biped robots. Since robots experience various disturbances during their locomotion, their walking mechanism should have the robustness against those disturbances, which requires an on-line adaptation capability. In this context, an on-line trajectory planner is proposed to compensate the required moment for recovering stability. The ZMP equation and sensed ZMP information are used in this trajectory generation strategy. In order to control a biped robot to be able to walk stably, its controller should guarantee stable footing at the moment of feet contacts with the ground as well as maintaining good trajectory tracking performance. Otherwise, the stability of robot will be significantly compromised. To reduce the magnitude of an impact and guarantee a stable footing when a foot contacts with the ground, this paper. proposes to increase the damping of the leg drastically and to modify the reference trajectory of the leg. In the proposed control scheme, the constrained leg is controlled by impedance control using the impedance model with respect to the base link. Computer simulations performed with a 3-dof environment model that consists of combination of a nonlinear and linear compliant contact model show that the proposed controller performs well and that it has robustness against unknown uneven surface. Moreover, the biped robot with the proposed trajectory generator can walk even when it is pushed with a certain amount of external force.

• 제어로봇시스템학회논문지
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• 제19권10호
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• pp.941-946
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• 2013

In this paper, an enhanced method for attitude determination is proposed for systems using an IMU (Inertial Measurement Unit). In attitude determination with IMU, it is generally assumed that the IMU can be located in the center of gravity on the vehicle. If the IMU is not located in the center of gravity, the accelerometers of the IMU are disturbed from additive accelerations such as centripetal acceleration and tangential acceleration. Additive accelerations are derived from the lever arm which is the distance between the center of gravity and the position of the IMU. The performance of estimation errors can be maintained in system with a non-zero lever arm, if the lever arm is estimated to remove the additive accelerations from the accelerometer's measurements. In this paper, an estimation using Kalman filter is proposed to include the lever arm in the state variables of the state space equation. For the Kalman filter, the process model and the measurement model for attitude determination are made up by using quaternion. In order to evaluate the proposed algorithm, both of the simulations and the experiments are performed for the simplified scenario of motion.

• 대한기계학회논문집A
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• 제21권1호
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• pp.144-153
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• 1997

The determination of the direct kinematics of the parallel mechanism is a difficult problem but has to be solved for any practical use. This paper presents the efficient formulation of the direct kinematics for double parallel robot arm. The robot arm consists of two parallel mechanism, which generate positional and orientational motions, respectively. These motions are decoupled by a passive central axis which is composed of four revolute joints and one prismatic joint. For a set of given lengths of linear actuators, the direct kinematics will find the joint displacements of th central axis from geometric constraints in each parallel mechanism. Then the joint displacements will be converted into the position and the orientation of the end effector of the robot arm. The proposed formulation is decoupled and compacted so that it will be implemented as a real-time direct kinematics. With the proposed formulation, we analyze the motion of the double parallel robot and show its characteristics. Specially, we investigate the workspace in terms of positional space as well as orientational space.

• 발명하는 사람들
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• 54호
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• pp.1-16
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• 2007

한국여성경제단체연합, 여성경제계 위해 공식 출범/발행인 칼럼/'마드리드 출원제도' 적극 활용 상표 침해 줄여라/일본 특허출원 심사기간 단축된다/기업.연구소 신입사원75%, 특허 관련 지식 전무/'주몽'이계인 씨 산자부 홍보대사 위촉/특허등록세, 신청 다음날 내도 된다/특허청, 6시그마 공공부문 혁신 주도/아듀 2006 한국여성발명협회 결산/자문위원 칼럼/로봇시장에도 브랜드 선점 열풍/농산물도 발명특허 상표 등록 시대/도소매업도 서비스업으로 출원 가능/기름대신 물 사용한 자동차, 항공기 현실화/반도체 배선 기술 특허 출원 상승세/자동차는 모바일 엔터네이너/'적외선 감지기술' 우리 생활속으로/서울반도체.바론테크, 일본 특허분쟁 승소/하나TV, 특허권 침해 피소/삼성전자, 분쟁.경쟁 대응위해 특허조직 통합/신한다이아몬드 일본 MDI 특허분쟁 승소/미니인터뷰/나노기술 응용한 디스플레이 특허출원 급증/미국의 두 배인 '휴면 특허', 대책 마련 시급/특허법원 "사용횟수 적다고 상표취소 못해"/종자번식 유전자 변형식물도 특허출원 가능/변리사 1차 시험 합격자 대폭 축소/역사 속의 발명품/하루 10분 발명교실/특허Q&A/신년인터뷰/화장하는 방법도 특허 받는다/'취업에서 결혼까지' 올인원 시스템 화제/아이디어 착상 및 발명 기법/아줌마의 힘이 발휘될 때까지 발명 또 발명/버뱅크의 식물 품종 개량/미국 청년, 몸짱 선탠용 티셔츠 발명/스위스, 국가경쟁력 1위의 비밀/저지방식,'유방암' 제발 위험 감소/서울대, 세계최초 암캐 복제 성공/국가 R&D 특허조사, 전체 R&D 부처로 확대/전국 초.중생 발명 글짓기.만화현상 공모전/특허청, 공공부문 성과주의 대통령상/한국여성발명협회 회원사 발명품 가이드

• 한국해양공학회지
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• 제23권6호
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• pp.53-60
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• 2009

Recently, since there are several problems in space, the infra-structure and the facilities in the contiguity of the existing harbors due to the trend of enlarging the container capacity of the large container vessel, a special floating platform named as the Mobile Harbor has been proposed conceptually as an effective solution of those problems. Two kinds of hull shapes, a conventional mono-hull type and a catamaran type, are proposed as midway feeders to transfer containers to the harbor on land from a large container ship on near shore. In this study, the motion response and mooring analysis are carried out for comparing the global performance of two types of Mobile Harbor. Robot arm mooring facility specially is devised and newly tried to use for the safe fixation of a large container ship and the Mobile Harbor on near shore. It would be expected for this comparison study to give a guideline to design the efficient hull form for a midway loader.