통합 검색 | Korea Science

이석희;이정헌;김희국;이병주
- 한국정밀공학회지
- /
- 제22권8호
- /
- pp.118-127
- /
- 2005
A spatial 3 degrees-of-freedom mechanism employing Stewart Platform structure is proposed: the mechanism maintains the 3- RRPS structure of Stewart Platform but has an additional passive PRR serial sub-chain at the center area of the mechanism in order to constrain the output motion of the mechanism within the output motion space of the added PRR serial subchain. The forward and reverse position analyses of the mechanism are performed. Then the mechanism having both the forward and the reverse closed-form solutions is suggested and its closed form solutions are derived. It is confirmed, through the kinematic analysis of those two proposed mechanisms via kinematic isotropic index, that both the proposed mechanisms have fairly good kinematic characteristics compared to the existing spatial 3-DOF mechanisms in literature.
PDF KSCI

이민기;최병오;김태성;박근우
- 대한기계학회:학술대회논문집
- /
- 대한기계학회 2000년도 추계학술대회논문집A
- /
- pp.535-540
- /
- 2000
This paper presents the development of a Parallel-Typed CNC Machining Tool. It is specially designed to machine a complex shaped workpiece by controlling the orientation of the tool. The inverse/direct kinematics of a parallel mechanism is derived and implemented in a PC based controller. With graphics icons, the GUI (Graphic User Interface) program is developed for the CNC programing. The calibration is accomplished by geometric constraint motion, which is a parallel motion of the platform with respect to a table. The calibration result is introduced and the future study is proposed.
PDF

김태성;정진욱;김용희;박근우;이민기
- 대한기계학회:학술대회논문집
- /
- 대한기계학회 2003년도 추계학술대회
- /
- pp.1512-1517
- /
- 2003
This paper presents the calibration for the parallel typed tilting table. The calibration system needs only simple sensing device which is a digital indicator to measure the orientation of a table. The calibration algorithm is developed by a measurement operator. It eliminates the concern about the poor parameter observability due to a large number of parameters of parallel-mechanism. This paper uses the QR-decomposition to find the optimal calibration configurations maximizing the linear independence of rows of a observation matrix. The number of identifiable parameters is examined by the rank of the observation matrix, which represents the parameter observability. The method is applied to a Parallel-typed Tilting Table and all the necessary kinematic parameters are identifiable.
PDF