• Journal of the Korean Society of Propulsion Engineers
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• v.20 no.1
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• pp.8-13
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• 2016

The purpose of the pyro-shock compliant joint is to isolated vibration using the compliant material in order to prevent the shock generated by pyro propulsion at the electronics equipment. The performance of the pyro-shock compliant joint can be determined by measuring bending natural frequency and transmissibility. In this study, we established the design requirements based on bending natural frequency and transmissibility results of the reference model. We developed a compliant material with sufficient shock compliant properties and a pyro-shock compliant joint for the new rocket. This results can be used to develop a pyro-shock compliant joint for any rocket using the compliant material and performance measurement.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.10
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• pp.1082-1090
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• 2008

In this paper, a general solution for the vibrational energy and intensity distribution through a compliant and dissipative joint between plate structures is derived on the basis of energy flow analysis (EFA). The joints are modeled by four sets of springs and dashpots to show their compliancy and dissipation in all four degrees of freedom. First, for the EFA, the power transmission and reflection coefficients for the joint on coupled plate structures connected at arbitrary angles were derived by the wave transmission approach. In numerical applications, EFA is performed using the derived coefficients for coupled plate structures under various joint properties, excitation frequencies, coupling angles, and internal loss factors. Numerical results of the vibrational energy distribution showed that the developed compliant and dissipative joint model successfully predicted the joint characteristics of practical structures vibrating in the medium-to-high frequency ranges. Moreover, the intensity distribution of a compliant and dissipative joint is described.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.1157-1160
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• 1996

Control of a biped robot which has compliant ankle joints is dealt in this paper. Simulated version of a human ankle joint is built using springs and mechanical constraints, which gives a flexibility of joint and compliance against the touching ground. The biped robot with compliant ankle joints proposed here gives a good contact between its sole and the ground and makes foot landing soft. As a result, installing force sensors for measuring the center of gravity of the biped becomes easier. A motor to drive an ankle joint is not needed which makes legs light. However, the control problem becomes more difficult because the torque of the ankle joint to put the biped in a desired walking gait cannot be provided from the compliant ankle joint. To solve this problem, we proposed a dynamic gait modification method by adjusting the position of a hip joint. Simulation results for the mathematical model of the SD-2 biped in the Ohio State University are given to show the validity of the proposed controller.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.2
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• pp.103-109
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• 2012

Fish generates large thrust through an oscillating motion with a compliant joint of caudal fin. The compliance of caudal fin affects the thrust generated by the fish. Due to the flexibility of the fish, the fish can generate a travelling wave motion which is known to increase the efficiency of the fish. However, a detailed research on the relationship between the flexible joint and the thrust generation is needed. In this paper, the compliant joint of a caudal fin is implemented in the driving mechanism of a robotic fish. By varying the driving frequency and stiffness of the compliant joint, the relationship between the thrust generation and the stiffness of the flexible joint is investigated. In general, as the frequency increases, the thrust increases. When higher driving frequency is applied, higher stiffness of the flexible joint is needed to maximize the thrust. The bending angles between the compliant joint and the caudal fin are compared with the changes of the thrust in one cycle. This result can be used to design the robotic fish which can be operated at the maximum thrust condition using the appropriate stiffness of the compliant joint.

• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.2983-2985
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• 1999

This paper presents the attitude control of the double inverted pendulum with compliant joint. The biped robot with compliant ankle joint instead of a motor have a good contact between it's sole and ground in the uneven ground. The compliant ankle joint proposed here is composed of springs and mechanical constraint. The lower link is hinged on the plate to free for rotation in the vertical plate. The upper link is connected to the lower link through a DC motor. The DC motor is used to control the posture of the pendulum by adjusting the position of the upper link. The algorithm for controlling a proposed inverted pendulum is nonlinear feedback controller. Simulation with mathematical model are conducted to show the validity of the proposed controller.

• The Journal of Korea Robotics Society
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• v.14 no.4
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• pp.237-244
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• 2019

This paper suggests novel types of joint mechanisms composed of elastic strings and rigid bodies. All of the human hinge joints have the articular capsule and a pair of collateral ligaments. These fibrous tissues make the joint compliant and stable. The proposed mechanism closely imitates the human hinge joint structure by using the concept of tensegrity. The resultant mechanism has several characteristics shown commonly from both the tensegrity structure and the human joint such as compliance, stability, lightweight, and non-contact between rigid bodies. In addition, the role and feature of the human hinge joints vary according to the origins of a pair of collateral ligaments. Likewise, the locations of two strings corresponding to a pair of collateral ligaments produce different function and motion of the proposed mechanism. It would be one of the advantages obtained from the proposed mechanism. How to make a joint mechanism with different features is also suggested in this paper.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.10 s.253
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• pp.1187-1193
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• 2006

Traditionally, the continuum-based topology optimization methods employing the SIMP technique have been used to design compliant mechanisms. Although they have been successful, the optimized mechanisms by the methods are usually difficult to manufacture because of their geometrical complexities. The objective of this study is to develop a topology optimization method that can produce easy-to-fabricate mechanism structure. The proposed method is a ground beam method where beam connectivity is controlled by the beam joint stiffness. In this approach, beam joint stiffness determines the mechanism configuration. Because b the ground structure beams have uniform thicknesses varying only discretely, the resulting mechanism topologies become easily manufacturable.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2010-2015
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• 2003

In this paper, a design and control of the safe arm with passive compliant joints(PCJ) is presented. Each PCJ has a magneto- rheological damper and maximum 6 springs. Compliance analysis in Cartesian space is performed with the compliance ellipsoid; this analysis shows a map between compliance in the joint space and compliance in Cartesian space. Vibration control of the arm using an input shaping technique is also presented; the results of a simulation and an experiment prove that a fast motion of the safe arm without residual vibration can be performed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.10a
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• pp.175-176
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• 2012

• 제어로봇시스템학회:학술대회논문집
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• 1990.10b
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• pp.1322-1326
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• 1990

In this paper, compliant motion control of a manipualator in manipulator is proposed by using the self-tuning adaptive controller. Compliant motion is needed in order to applicated to complicated and accurate fields such as assembly operation in which several parts are matched. For a control method of compliant motion hybrid control is used so forces and position control are proposed selectively through a closed feedback loop. By contacting with environment, the uncertainties higher. Self-tuning controller which adapts to variable dynamic response is applied to compliant motion control in order to satisfy the desired operation. The applicability of the suggested algorithm was confirmed by simulation of the contour tracking task of four joint manipulator.