• Title/Summary/Keyword: mechanism

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The Present Situation and Prospects of Chinese National Mechanism on Space Debris Mitigation

  • Li, Shouping
    • The Korean Journal of Air & Space Law and Policy
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    • v.26 no.2
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    • pp.239-258
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    • 2011
  • Space debris mitigation has become an international custom for international space activities. IADC and COPUOS adopted a Guideline on Space Debris Mitigation. Two Guidelines provided that member states or international organization shall establish a national mechanism to mitigate space debris. China has made progress in legislation on space debris mitigation and management system. It establised a fundamental framework on the legislative mechanism on space debris mitigation and managemental mechanism on space debris mitigation. In order to further improve the national mechanism on space debris mitigation, it is essential for China to strenghen legislation on space activities and specify the duties of management administrates.

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Investigation of Spalling Mechanism in High Performance Concrete Subjected to Fire (고성능 콘크리트의 화재시 폭렬성상에 관한 메카니즘 고찰)

  • Han, Min-Cheol;Kim, Seong-Hwan;Park, Yong-Kyu;Heo, Young-Sun;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2006.11a
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    • pp.99-102
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    • 2006
  • This paper reviews the relevant literatures and investigates spalling mechanism of high strength concrete, in order to clearly inform spalling problem in fire. Firstly, we studies literatures on spalling occurrence and resistance methods. Secondly chemical change of concrete components in elevated temperature was presented. Finally, mechanism of the spalling occurrence and spalling resistance were carried out with fiber content. In addition, our research team introduced spalling mechanism, being different from other points of view, which has been generally accepted. To secure this mechanism theory, we investigate spalling properties of certain specimens fabricated by roller spindle and made with mortar or concrete condition.

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Design and Analysis of Power Circuit Breaker Mechanism Based on the Dynamic Model (동적모델에 기반한 고압회로차단기의 설계 및 해석)

  • Kwon, B.H.;Ahn, K.Y.;Oh, I.S.;Seo, J.M.;Kim, S.H.
    • Proceedings of the KSME Conference
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    • 2001.06b
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    • pp.476-481
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    • 2001
  • In this paper, based on the developed dynamic model of a vacuum circuit breaker mechanism, the development of the new circuit breaker with less energy mechanism is focused. The energy flow analysis of the original mechanism is carried out to show where the elastic potential energies of pre-loaded springs are transmitted. Through energy flow analysis, the concept design of the new circuit breaker with less energy mechanism is proposed, and then the detailed design is carried out through the design process based on the verified dynamic model. Comparing simulation results with experiment using a high-speed camera, the appropriateness of the proposed design procedures for the rapid circuit breaker mechanism is shown.

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Displacement Characteristics of a Parallel Leaf Spring Mechanism with Large-Deflective Elastic Hinges for Optical Mount

  • Kim, Kwang;Mikio Horie;Teruya Sugihara
    • 제어로봇시스템학회:학술대회논문집
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    • 1998.10a
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    • pp.484-489
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    • 1998
  • In this paper, we examine the displacement characteristics of the parallel leaf spring mechanism with large-deflective elastic hinges, and the validity of this mechanism as a translational and rotational mechanism is confirmed with multi-input system. This study is focused on the linear driving force as an input force, which is applied to the large-deflective elastic mechanism, and the displacement characteristics are discussed with theoretically and experimentally. The motions of this mechanism due to large-deflective hinges are changed by the position of loading force regardless of a single driving force. The numbers of degree of freedom are increased with the hinges, and we can be used to a multiple driving force in order to obtain many types of Output.

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Design of optimized legged robots for safety structure using Jansen Mechanism and m.Sketch (Jansen Mechanism 과 m.Sketch 를 활용한 보행 로봇의 안전 최적 설계.)

  • Woo, Minhyuk
    • Proceeding of EDISON Challenge
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    • 2016.03a
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    • pp.469-472
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    • 2016
  • Jansen Mechanism has been a constant popularity by researchers studying legged robots because of many benefits. This paper proposed the design process of optimized legged robots using Jansen Mechanism and m.Sketch(Jansen Mechanism simulation software). First, driving part of legged robots is designed in compliance with the design regulations of a competitive exhibition. Second, setting the length of link and position of joint is conducted in keeping with the constraints. Third, Ground Length (GL) and Ground Angle Coefficient(GAC) values are extracted by m.Sketch simulation. Finally, by repeating the previous procedures, comparing the GL and GAC values, find the optimum input values. This.

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Designing walking robot using Theo Jansen Mechanism (Theo Janson Mechanism 을 이용한 보행 로봇 설계)

  • Lee, Byeongcheol
    • Proceeding of EDISON Challenge
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    • 2016.03a
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    • pp.411-416
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    • 2016
  • Existing moving robots has several kinds of moving method; using wheel, jointed leg structure and so on. Wheel type can be operated by DC motor so it is simple and efficient. However, it is not appropriate to pass irregular terrain and obstacle. Leg structure type has an advantage in those cases. Generally, Leg structure is operated by several servo motors attached to each joint. It makes a robot heavier and more complicate due to increase of the degree of freedom. However, by using Theo Jansen Mechanism, one (or more) leg have only single-degree of freedom and can be operated by only one DC motor. So leg structure using Theo Jansen Mechanism will be good choice if robots have to be mass-produced. This paper describes the following a walking robot designed and produced based on Theo Jansen Mechanism, simulating process of Theo Jansen leg structure using Edison m.Sketch and how to solve several of discovered problem of the robot.

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Design of Robot Using of Jansen Mechanism (얀센메커니즘을 이용한 로봇 설계)

  • Kim, beong jin;Kim, hyeon min;Lee, hyo jung
    • Proceeding of EDISON Challenge
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    • 2016.03a
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    • pp.501-505
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    • 2016
  • In this study, a robot is implemented in H/W based on four-bar linkage mechanism and Jansen mechanism. Our goal is to finish the given path using given terms. The various programs was used to understand the mechanism in more detail. DISON m.Sketch, EDISON Designer, Theo Jansen Mechanism Optimization Solver. Using these programs, we can design the robot in more dtails and reduce errors and trials. For the design and implementation of a robot, it is need to get joint variable, a foot point, and their relation. Thus, the proposed kinematic analysis is very important process for the design and implementation of legged robots.

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A Geometrical Approach to the Characteristic Analysis of Parallel Mechanism for Planar Task (평면 작업용 병렬 메카니즘의 특성 해석을 위한 기하학적 접근)

  • Song, Nak-Yoon;Cho, Hwang
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.9
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    • pp.158-166
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    • 1998
  • This paper presents a geometrical approach to the characteristic analysis of parallel mechanism with free joints intended for use as a planar task robot. Solution of the forward and inverse kinematic problems are described. Because the mechanism has only three degree-of-freedom output, constraint equations must be generated to describe the inter-relationship between actuated joints and free joints so as to describe the position and orientation of the moving platform. Once these constraints are incorporated into the kinematics model, a constrained Jacobian matrix is obtained. and it is used for the solution of the forward kinematic equations by Newton-Raphson technique. Another Jacobian matrix was derived to describe the interrelationship between actuated joints and moving platform. The stiffness, velocity transmission ratio, force transmission ratio and dexterity of the mechanism are then determined based on this another Jacobian matrix. The geometrical construction of the mechanism for the best performance was investigated using the characteristic analysis.

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High Speed Tool Feed System by the Mechanism of Ball Screw and Servo Motor (볼 나사와 서보모터 메커니즘에 의한 고속 TOOL 이송장치)

  • 김성식;김경석
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.11
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    • pp.76-82
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    • 1998
  • In this study, the Ball screw and Servo motor Mechanism is considered as a High Speed Tool Feed System for the machining of a piston of a reciprocating engine. For the machining of a piston, that shapes oval, high speed servo mechanism is needed as a positioning of a cutting tool, and the stroke of tool is 0.1 mm ~ 1 mm. Ball screw and servo motor Mechanism is available very much because this mechanism is used widely in general machine. This Mechanism has been designed with the use of the decrease in mass and partial wear of the ball screw for high speed positioning of tool. Also the periodic learning control method with the inverse transfer function compensation has been applied to the positioning control for the high accuracy positioning of tool. These applications lead the achievement of the machining of a piston with an accuracy of 5${\mu}{\textrm}{m}$ at 2500 rpm in CNC turning.

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Design of Switch Mechanism of Electric Contact Using Double Scotch Yoke Mechanism (이중 스카치 요크 기구를 이용한 접점 개폐 메커니즘의 설계)

  • Yang H.I.;Ahn K.Y.;Jeong K.Y.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.10a
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    • pp.804-807
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    • 2005
  • In this paper, a double scotch yoke mechanism for moving simultaneously the fixed contact and moving contact of a gas circuit brake, is proposed and designed to improve the breaking characteristics of the circuit breaker. Firstly, the design parameters of the scotch yoke are kinematically determined from the desired design condition of the circuit breaker. Next, the stroke curve of the moving contact is designed by considering the design parameter and the specified opening characteristics of electric contacts. Based on the scotch yoke and stroke curve, the dynamics of the electric contacts is analyzed using ADAMS model of switch mechanism.

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