• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.11a
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• pp.115-116
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• 2007

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2008.04a
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• pp.223-226
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• 2008

This paper presents an effectiveness of a four-link mechanism with a tip which has four joints, but only one is an active joint. Even though the degree-of-freedom of the mechanism is one, it can be applied to implement a combined joint motion adequately. So, this paper analyzes its motion for effective robotic applications.

• The Journal of Korea Robotics Society
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• v.14 no.4
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• pp.245-250
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• 2019

Milli-scale crawling robots have been widely studied due to their maneuverability in confined spaces. For successful crawling, the crawling robots basically required to fulfill alternating gait with elliptical foot trajectory. The alternating gait with elliptical foot trajectory normally generates both forward and upward motion. The upward motion makes the aerial phase and during the aerial phase, the forward motion enables the crawling robots to proceed. This simultaneous forward and upward motion finally results in fast crawling speed. In this paper, we propose a novel alternating mechanism to make a crab-inspired eight-legged crawling robot. The key design strategy is an alternating mechanism based on double four-bar linkages. Crab-like robots normally employs gear-chain drive to make the opposite phase between neighboring legs. To use the gear-chain drive to this milli-scale robot system, however, is not easy because of heavy weight and mechanism complexity. To solve the issue, the double-four bar linkages has been invented to generate the oaring motion for transmitting the equal motion in the opposite phase. Thanks to the proposed mechanism, the robot crawls just like the real crab with the crawling speed of 0.57 m/s.

• 제어로봇시스템학회:학술대회논문집
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• 1987.10b
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• pp.264-268
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• 1987

This paper is concerned on kinematic analysis and simulation of an automatic feeding mechanism subjected by the motion of a curvilinear inverse can. The curvilinear cam is rotated by positioning a translating roller and the automatic feeding mechanism is moved to the sliding position by the motion of a campin fixed on the curvilinear cam. The curvilinear cam consists of two arcs of circles and two straight lines. The modular approach is used for the kinematic analysis of the feeding mechanism. As the first part of the paper for the motion simulation of the cam-feeding system, this paper discusses the algorithm to simulate the motion of the cam-feeding mechanism. The second part of the paper presents the state-of-art for the graphics-oriented CAD technique,

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.336-336
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• 2000

This paper studied on the yaw motion of the gantry crane which is used for the automated container terminal. Though several problems are occurred in driving of gantry crane, they are solved by the motion by the operator. But if the gantry crane is unmanned, it is automatically controlled without any human operation. There are two types, cone and flat typo in driving wheel shape. In cone type, lateral vibration and yaw motion of crane are issued. To bring a solution to these problems, the dynamic equation of the gantry crane driving mechanism is derived and it used PD(Proportional-Derivative) controller to control the lateral vibration. The simulation result of the driving mechanism using the Runge-Kutta method is presented in this paper.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.12
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• pp.48-54
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• 1998

In sewing, fabrics is fed by an elliptic motion of the feed dog. The feeding control mechanism controls an elliptic motion of the feed dog, finally, controls stitch spacings and feeding directions of fabrics. This study discusses the feeding control mechanism of an industrial lock stitch sewing machine, which is a good example to study a machine kinematics. This study makes mathematical expressions of machine's motion in the feeding control mechanism. Thus, the motions of this mechanism are characterized, which will be used for kinematic analysis of the feed dog later. Also, the above mathematical expressions may be a basis for the new design of the feeding control mechanism and may be applied to development of the similar feeding control mechanism of other type sewing machine.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.1 s.94
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• pp.125-131
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• 1999

For linkage mechanisms driven by a cam, cam profile is the major design factor and is determined by the cam follower motion. If a cam mechanism has additional kinematic linkage besides cam and follower then the follower motion should be specified from the motion of end linkage member so that cam would be able to generate the desired end linkage motion. In this paper, a cam-linkage mechanism is constructed with the combinations of modular linkage elements including cam and follower and as a result, a planar cam-linkage mechanism design software with the cam profile optimization function is developed and presented.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.822-826
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• 2008

A linkage mechanism is a device to convert an input motion into a desired output motion. Traditional linkage mechanism designs are based on trial and error approaches so that size or shape changes of an original mechanism often result in improper results. In order to resolve these problems, an improved automatic mechanism synthesis method that determines the linkage type and dimensions by using an optimization method during the synthesis process has been proposed. For the synthesis, a planar linkage is modeled as a set of rigid blocks connected by zero-length translational springs with variable stiffness. In this study, the sizes of rigid blocks were also treated as design variables for more general linkage synthesis. The values of spring stiffness and the size of rigid block yielding a desired output motion at the end-effecter are found by using an optimization method.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.965-968
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• 2004

This paper describes the development of the test path for Eclipse-II, a parallel mechanism motion simulator. Eclipse-II which can be used as a base for general motion simulators, enables unlimited continuous 360-degree spinning in any rotational axes plus finite X, Y, and Z translation motions. The advantage of enabling continuous 360-degree spinning allows various motions for virtual reality. In this paper, the development of the test path to verify the robustness of the Eclipse-II motion simulator is described. The test motions, which satisfy the requirements of test path, are suggested and washout filter enables these motions reproduced in the limited workspace. The trial run is conducted to verify the robustness of the Eclipse-II motion simulator. Additionally the standard data format of virtual reality for Eclipse-II One Man Ride is suggested.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.485-486
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• 2006

This paper represents a ultra precision rotational device where the smooth impact drive mechanism(SIDM) is utilized as a driving mechanism. Linear motions of piezoelectric elements are converted to the rotational motion of disk by frictional forces generated between the rotational disk and the friction bars which are attached to the piezoelectric elements. This device was designed to drive a rotational disk using slip-slip motion mechanism based on stick-slip motion mechanism. Experimental results show that the angular velocity was increased in proportion to the magnitude of supplied voltage to piezoelectric element. In our device, the smooth rotational motion was obtained when the driving frequency has been reached to 500Hz under the driving voltage of 100V. The amount of step movement has been revealed to be $3.44{\times}10^{-4}$ radian.