• 제목/요약/키워드: Mechanical interaction

검색결과 1,841건 처리시간 0.04초

능동 분할 오프셋 캐스터 기반 전방향 차량의 설계 및 제어 (Design and Control of the Active Split Offset Caster based Omni-directional Vehicle)

  • 김한결;;박종찬;권동수
    • 로봇학회논문지
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    • 제8권2호
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    • pp.75-81
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    • 2013
  • This research would investigate deeply the operation of an omni-directional mobile robot that is able to move with high acceleration. For the high acceleration performance, the vehicle utilizes the structure of Active Split Offset Casters (ASOCs). This paper is mainly focused on inverse kinematics of the structure, hardware design to secure durability and preserve the wheels' contact to the ground during high acceleration, and localization for the real time position control.

Effect of cavity-defects interaction on the mechanical behavior of the bone cement

  • Zouambi, Leila;Serier, Boualem;Benamara, Nabil
    • Advances in materials Research
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    • 제3권1호
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    • pp.271-281
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    • 2014
  • The presence of cavities in the bone cement has a great importance for the transport of antibiotics, but its existence in this material can lead to its weakening by notch effect. The aim of this study allows providing a physical interpretation to the cavities interconnection by cracks observed experimentally. The most important stress of Von Mises is localized at the cement/bone interface near the free edge which is the seat of stress concentration. The presence and interaction of cavities in this site concentrate, by notch effect, stresses which tend to the tensile fracture stress of Bone cement.

Design of Smart flap actuators for swept shock wave/turbulent boundary layer interaction control

  • Couldrick, Jonathan;Shankar, Krishnakumar;Gai, Sudhir;Milthorpe, John
    • Structural Engineering and Mechanics
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    • 제16권5호
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    • pp.519-531
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    • 2003
  • Piezoelectric actuators have long been recognised for use in aerospace structures for control of structural shape. This paper looks at active control of the swept shock wave/turbulent boundary layer interaction using smart flap actuators. The actuators are manufactured by bonding piezoelectric material to an inert substrate to control the bleed/suction rate through a plenum chamber. The cavity provides communication of signals across the shock, allowing rapid thickening of the boundary layer approaching the shock, which splits into a series of weaker shocks forming a lambda shock foot, reducing wave drag. Active control allows optimum control of the interaction, as it would be capable of positioning the control region around the original shock position and unimorph tip deflection, hence mass transfer rates. The actuators are modelled using classical composite material mechanics theory, as well as a finite element-modelling program (ANSYS 5.7).

세포와 흡착면간의 영향을 고려한 흡착형 세포의 3 차원 동적 해석 모델 개발 (Development of Three-dimensional Chemotaxis Model for a Single Crawling Cell, Considering the Interaction between the Cell and Substrate)

  • 송지환;김동철
    • 대한기계학회논문집A
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    • 제35권11호
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    • pp.1355-1360
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    • 2011
  • 흡착형 세포의 이동에 있어 세포와 바닥면간의 상호작용은 매우 중요한 역할을 한다. 본 논문은 주화성에 의한 흡착형 세포의 이동에 있어 세포와 바닥면과의 상호작용에 따른 영향을 보이기 위해 확산계면모델을 바탕으로 한 3 차원의 입체 모델을 제안한다. 세포와 바닥면간의 영향을 표현하기 위해 세포 주위 물질과의 관계를 고려한 경계에너지를 고려하였다. 본 연구에서 적용한 확산계면모델은 경계에너지, 주화성, 확산성을 모두 고려한 다중 메커니즘 모델로서 흡착형 세포이동의 역학적 특성을 정확히 예측하는데 있어 높은 신뢰성을 보일 것이라 기대된다.

Recent Progress of Spray-Wall Interaction Research

  • Lee Sang-Yong;Ryu Sung-Uk
    • Journal of Mechanical Science and Technology
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    • 제20권8호
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    • pp.1101-1117
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    • 2006
  • In the present article, recent progress of spray-wall interaction research has been reviewed. Studies on the spray-wall interaction phenomena can be categorized mainly into three groups: experiments on single drop impact and spray (multiple-drop) impingement, and development of comprehensive models. The criteria of wall-impingement regimes (i.e., stick, rebound, spread, splash, boiling induced breakup, breakup, and rebound with breakup) and the post-impingement characteristics (mostly for splash and rebound) are the main subjects of the single-drop impingement studies. Experimental studies on spray-wall impingement phenomena cover examination of the outline shape and internal structure of a spray after the wall impact. Various prediction models for the spray-wall impingement phenomena have been developed based on the experiments on the single drop impact and the spray impingement. In the present article, details on the wall-impingement criteria and post-impingement characteristics of single drops, external and internal structures of the spray after the wall impact, and their prediction models are reviewed.

디지털영상처리기술을 이용한 비접촉식 유체-구조물 연동운동 3차원 측정시스템 개발에 관한 연구 (A Study on the Development of a Three-dimensional Measurement System for Flow-Structure Interaction Using Digital Image Processing)

  • 도덕희;조효제;상지웅;황태규;조용범;편용범
    • 한국해양공학회지
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    • 제18권4호
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    • pp.1-7
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    • 2004
  • A simultaneous measurement system that can analyze the flow-structure interaction has been developed. This system consists of four CCD cameras, two for capturing instantaneous flow fields and two for tracking a solid body. The three-dimensional vector fields around a cylinder are measured, while the motion of the cylinder forced by the flow field is measured, simultaneously, with the constructed system. The cylinder is suspended in the working fluid of a water channel, and the surface of the working fluid is forced sinusoidally to make the cylinder bounced. Reynolds number for the mean main stream is about 3500. The interaction between the flow fields and the cylinder motion is examined quantitatively.

A new human-robot interaction method using semantic symbols

  • Park, Sang-Hyun;Hwang, Jung-Hoon;Kwon, Dong-Soo
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2004년도 ICCAS
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    • pp.2005-2010
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    • 2004
  • As robots become more prevalent in human daily life, situations requiring interaction between humans and robots will occur more frequently. Therefore, human-robot interaction (HRI) is becoming increasingly important. Although robotics researchers have made many technical developments in their field, intuitive and easy ways for most common users to interact with robots are still lacking. This paper introduces a new approach to enhance human-robot interaction using a semantic symbol language and proposes a method to acquire the intentions of robot users. In the proposed approach, each semantic symbol represents knowledge about either the environment or an action that a robot can perform. Users'intentions are expressed by symbolized multimodal information. To interpret a users'command, a probabilistic approach is used, which is appropriate for interpreting a freestyle user expression or insufficient input information. Therefore, a first-order Markov model is constructed as a probabilistic model, and a questionnaire is conducted to obtain state transition probabilities for this Markov model. Finally, we evaluated our model to show how well it interprets users'commands.

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트로카 고정부에 작용하는 반력을 측정하여 수술도구 말단의 수직방향 상호작용 힘을 추정하는 방법 (Estimation of Vertical Interaction Force to the End of a Surgical Instrument by Measuring Reaction Force to the Trocar Support)

  • 김수용;김청준;이두용
    • 제어로봇시스템학회논문지
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    • 제22권8호
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    • pp.615-618
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    • 2016
  • This paper proposes a method to estimate vertical interaction force to the end of the surgical instrument by measuring reaction force at the part supporting the trocar. Relation between the force to the trocar and the interaction force is derived using the beam theory. The vertical interaction force is modeled as a function of the reaction force to the trocar and the distance between the drape plate and the trocar. Experimental results show that error is induced by the asymmetric shape of the trocar tip because contact position between the instrument and the trocar tip is changed depending on the direction of the interaction force. The theoretical relation, therefore, is compensated and reduced. Average $L_2$ relative error of the estimated force in the x-direction and the y-direction is 5.81 % and 5.99 %, respectively.

가용 에너지에 의한 열역학의 재구성 (II) - 실제세계 열역학 - (Reconstruction of Thermodynamics by the Concept of Available Energy (II) - Thermodynamics of Real World -)

  • 정평석
    • 대한기계학회논문집B
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    • 제28권12호
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    • pp.1573-1581
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    • 2004
  • Thermodynamic principles are described with a new point of view. In present study, the interaction between two systems is focused instead of the behavior of a system in conventional thermodynamics. The state change of a system cannot occur by itself but it is the result of the interaction between systems. However, the interaction itself is also the result of another kind of interaction, the interaction between two interactions. To reconstruct thermodynamics with such a point of view, the reversible world is imagined, in which conservations and measurements are discussed. There exists a conserved quantity for each mode of reversible interaction. The conserved transferring quantity in the interaction between interactions is the effective work, which is supposed to be measurable and conserved in reversible world. Effective work is the primary concepts of energy. It is the key factor to explain measurements, energy conservation and energy dissipation. The concepts developed in reversible world are applied to the real world in which irreversible phenomena may occur. Irreversibility is the result of effective energy dissipation, in which effective work irreversibly changes into entropy. A quantitative relation between the disappearing effective work and the generated entropy is dissipation equation which is given by experiments. A special temperature scale to give a very simple type of the dissipation equation is the absolute temperature scale, which gives the conventional conservation of energy.