• 제목/요약/키워드: Spring backbone

검색결과 8건 처리시간 0.013초

스프링 구조를 이용한 4자유도 연속체 로봇의 개발 (Development of a 4-DOF Continuum Robot Using a Spring Backbone)

  • 윤현수;이병주
    • 로봇학회논문지
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    • 제3권4호
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    • pp.323-330
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    • 2008
  • This work deals with a 4-DOF flexible continuum robot that employs a spring as its backbone. The mechanism consists of two modules and each module has 2 DOF. The special features of the proposed mechanism are the flexibility and the backdrivability of the whole body by using a spring backbone. Thus, even in the case of collision with human body, this device can ensure safety. The design and the kinematics for this continuum mechanism are introduced. The performance of this continuum mechanism was shown through simulation and experiment.

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스프링 백본과 와이어를 이용한 3자유도 내시경 (3DOF Endoscope with Spring Backbone and Wires)

  • 최동걸;이병주
    • 로봇학회논문지
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    • 제3권3호
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    • pp.203-211
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    • 2008
  • This work proposes structure of spring backbone micro endoscope. For effective surgery in narrow and limited space, many manipulators are developing that different to existed structure. This device can move like elephant nose or snake unlike the existing robots. For this motion, a mechanism that uses spring backbone and wires has been developed. The new type endoscope that has Z axis motion for spring structure, therefore it has 3 degree of freedom, two rotations and one linear motion. And new kinematics for backbone structure is proposed using simple geographic analysis. The Jacobian and stiffness modeling are also derived. Exact actuator sizing is determined using stiffness model. Finally, the proposed kinematics are verified by simulation and experiments.

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인간 동작 표현용 스프링 백본 구조 소프트 암의 구현 (Implementation of a Spring Backboned Soft Arm Emulating Human Gestures)

  • 윤현수;최재연;오세민;이병주;윤호섭;조영조
    • 로봇학회논문지
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    • 제7권2호
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    • pp.65-75
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    • 2012
  • This study deals with the design of a spring backboned soft arm, which will be employed for generation of human gesture as an effective means of Human Robot interaction. The special features of the proposed mechanism are the light weight and the flexibility of the whole mechanism by using a spring backbone. Thus, even in the case of collision with human, this device is able to absorb the impact structurally. The kinematics and the design for the soft arm are introduced. The performance of this mechanism was shown through experiment emulating several human gestures expressing human emotion and some service contents. Finally, this soft arm was implemented as the wing mechanism of a penguin robot.

Simplified beam-column joint model for reinforced concrete moment resisting frames

  • Kanak Parate;Onkar Kumbhar;Ratnesh Kumar
    • Structural Engineering and Mechanics
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    • 제89권1호
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    • pp.77-91
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    • 2024
  • During strong seismic events, inelastic shear deformation occurs in beam-column joints. To capture inelastic shear deformation, an analytical model for beam-column joint in reinforced concrete (RC) frame structures has been proposed in this study. The proposed model has been developed using a rotational spring and rigid links. The stiffness properties of the rotational spring element have been assigned in terms of a moment rotation curve developed from the shear stress-strain backbone curve. The inelastic rotation behavior of joint has been categorized in three stages viz. cracking, yielding and ultimate. The joint shear stress and strain values at these stages have been estimated using analytical models and experimental database respectively. The stiffness properties of joint rotational spring have been modified by incorporating a geometry factor based on dimensions of adjoining beam and column members. The hysteretic response of the joint rotational spring has been defined by a pivot hysteresis model. The response of the proposed analytical model has been verified initially at the component level and later at the structural level with the two actually tested RC frame structures. The proposed joint model effectively emulates the inelastic behavior precisely with the experimental results at component as well as at structural levels.

지진하중을 받는 말뚝 시스템의 고유 진동수 예측 (Prediction of the Natural Frequency of a Soil-Pile-Structure System during an earthquake)

  • 양의규;권선용;최정인;김명모
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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    • pp.976-984
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    • 2009
  • This study proposes a simple method that uses a simple mass-spring model to predict the natural frequency of a soil-pile-structure system in sandy soil. This model includes a pair of matrixes, i.e., a mass matrix and a stiffness matrix. The mass matrix is comprised of the masses of the pile and superstructure, and the stiffness matrix is comprised of the stiffness of the pile and the spring coefficients between the pile and soil. The key issue in the evaluation of the natural frequency of a soil-pile system is the determination of the spring coefficient between the pile and soil. To determine the reasonable spring coefficient, subgrade reaction modulus, nonlinear p-y curves and elastic modulus of the soil were utilized. The location of the spring was also varied with consideration of the infinite depth of the pile. The natural frequencies calculated by using the mass-spring model were compared with those obtained from 1-g shaking table model pile tests. The comparison showed that the calculated natural frequencies match well with the results of the 1-g shaking table tests within the range of computational error when the three springs, whose coefficients were calculated using Reese's(1974) subgrade reaction modulus and Yang's (2009) dynamic p-y backbone curves, were located above the infinite depth of the pile.

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4자유도 새로운 소프트 핑거 설계 (Design of a new 4-DOF soft finger mechanism)

  • 차효정;이병주
    • 로봇학회논문지
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    • 제3권4호
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    • pp.315-322
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    • 2008
  • A new soft finger mechanism using a spring as a backbone is proposed in this work. It is a 4 DOF mechanism that consists of a spring and 3 cylinders, which behave like joints with 3 up-and-down rotations and 1 left-and-right rotation. To control each joint, cylinders have small holes in their cross-sectional areas, and wires of different length are penetrated into these holes. We can control each joint by pulling the corresponding wire. The forward kinematics is solved by using the geometry of mechanism. And the relationship (Jacobian) between the linear velocity of the wires and the joint angular rate is obtained. A virtual simulator is developed to test the validity of the kinematic model. In the experiment, first, the position control is conducted by tracking a given trajectory. Second, to verify the flexibility and safety, we show that the soft finger deflects in a safe manner, in spite of the collision with environment.

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국조리의 과학화에 관한 연구 - 맑은장국을 중심으로 - (A Study on the standardizing of Recipe for Soup Making - Focused on Clear Soup -)

  • 홍진숙
    • 한국식품조리과학회지
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    • 제15권6호
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    • pp.595-602
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    • 1999
  • This study was intended to develop traditional Korean soup recipe which can be used for food service and meet consumers' taste with a focus on clear soup such as clear radish soup, sea mustard soup, dried pollack soup, croaker soup, and backbone soup. The developed sample(S1) showed the highest level of overall preference among consumers. There were significant differences in sensory characteristics of the samples especially between S1 and others. The sensory characteristics of each soup showed a slight difference depending on the kind of soup, however, all items had an effect on overall preference. One of the standardized recipe to make broth was presented as follows: The ingredients for broth consists of the shank or brisket of beef(100 g), water(10 cup), spring onion(20 g), onion(30 g), garlic(10 g), salt(1 teaspoonful), and black pepper power(1/10 teaspoonful). 1) The meat part of shank or brisket is prepared. 2) The unfrozen meat is immersed in cold water for 20 min, whereby blood is extracted from the meat. 3) 10 cups of water are poured into the pan and boiled enough. 4) After water has boiled enough, the lump of meat with blood extracted is cut into 2 or 3 pieces and is boiled in the boiling water by high-intensity heat with the pan lid uncovered, and dirty foam is scooped out while boiling. 5) If the broth begins to be extracted, the intensity of heat is lowered for boiling for one hour or so, and then again boiled for 30 min with spring onion, garlic, onion and the like. If the broth is extracted enough, spring onion, garlic, onion, and others are removed from the pan. the broth is seasoned with salt and black pepper powder, and foam is removed by using fine mesh sieve or gauze. Then, 6 cups of clear broth is obtained finally.

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사질토 지반에 놓인 지진하중을 받는 말뚝 기초 시스템의 고유 진동수 예측 (Prediction of the Natural Frequency of Pile Foundation System in Sand during Earthquake)

  • 양의규;권선용;최정인;김명모
    • 한국지반공학회논문집
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    • 제26권1호
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    • pp.45-54
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    • 2010
  • 말뚝 구조물의 동적 거동을 분석하고 지진파에 대한 공진 안정성을 확보하기 위해서는 고유 진동수를 합리적으로 산정하는 것이 중요하다. 본 연구에서는 간단한 질량 - 스프링 모델을 이용하여 지진 하중을 받는 말뚝 구조물의 고유 진동수를 간편하면서도 효율적으로 예측할 수 있는 방법을 모색하였다. 고유진동수 산정 결과에 큰 영향을 미치는 지반-말뚝 간 스프링 강성을 지반반력상수와 p-y 곡선 그리고 지반 탄성계수 등을 이용하여 결정하고, 이들을 이용하여 계산한 고유진동수를 1g 진동대 실험에서 계측한 고유진동수와 비교한 결과, 지반반력상수를 이용한 Reese(1974) 방법과 동적 p-y 중추 곡선을 이용한 Yang(2009)의 방법을 이용하여 스프링 강성을 산정하는 것이 가장 우수한 결과를 나타내었는데, 건조토에 위치한 말뚝구조물에서는 5% 이내의 오차를 보였으며, 포화토에 위치한 말뚝 구조물의 경우에는 진동 중에 과잉간극수압의 발생여부에 따라 5%에서 40% 사이의 오차를 나타내었다.