• 대한기계학회논문집A
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• 제31권1호
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• pp.43-49
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• 2007

A new electric coil design methodology using the notion of topology optimization is developed. The specific design problem in consideration is to find optimal coil configuration that maximizes the Lorentz force under given magnetic field. Topology optimization is usually formulated using the finite element method, but the novel feature of this method is that no such partial differential equation solver is employed during the whole optimization process. The proposed methodology allows the determination of not only coil shape but also the number of coil turns which is not possible to determine by any existing topology optimization concept and to perform single coil strand identification algorithm. The specific applications are made in the design of two-dimensional fine-pattern focusing coils of an optical pickup actuator. In this method, the concept of equivalent magnetizing current is utilized to calculate the Lorentz force, and the optimal coil configuration is obtained without any initial layout. The method is capable of generating the location and shape of turns of coil. To confirm the effectiveness of the proposed method in optical pickup applications, design problems involving multipolar permanent magnets are considered.

• 센서학회지
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• 제14권1호
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• pp.1-6
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• 2005

This paper describes a novel concept of a chemically sensitive scanning force microscope (CS-SFM). It consists of the conventional SFM and the time-of-flight mass spectrometer (TOF-MS). A switchable cantilever (SC) fabricated by the micromachining technology combines each advantage of two completely different systems, SFM and TOF-MS. The CS-SFM offers to produce both images of topography and chemical information simultaneously. First we employed a rotatable tip holder based on 4 piezotube actuators for demonstration of the possibility of the CS-SFM concept. Second the CS-SFM concept is optimized with the micromachining technology. The micromachined SC with an integrated bimorph actuator and a piezoresistive strain sensor provides a reasonable switching speed of ${\sim}10$ ms which is very attractive for the CS-SFM application. The SC is currently being integrated in an ultra-high-vacuum system to perform various experiments.

• 대한기계학회논문집A
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• 제33권11호
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• pp.1353-1356
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• 2009

As a method obtaining linear thrust force for the magnet wheel producing a strong traction torque, the concept of magnetic shield is suggested and compared with the existing approaches. Specially, as the magnet wheel, in which the permanent magnets rotate mechanically instead of ac driving to make traveling field, is physically similar with the rotary induction motor, there is a periodical force ripple in tangential direction as well as normal direction. But, the force ripple can be suppressed from a shape change of the shield plate. Namely, the change brings out a change of entry and exit effect of the circumferential field for the magnet wheel. The feasibility of the shield concept is verified from simulation and experiment.

• 국방과기술
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• 1호통권287호
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• pp.86-93
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• 2003

Objective Force의 모든 측면에서 볼 때, 육군항공은 절대 필요한 구성요소이다. 통합개념팀(Intergrated Concept Team)은 현재 Alabama주 Fort Rucker에서 미래 항공력에 대한 작전적 및 조직적(O & O : Operational and Organizational) 개념을 개발하고 있는 중이다. 이러한 노력은 무인항공기, 공중기동수송기, Loitering Attack Munition – Aviation, 새로운 군수 및 공중수송서비스 등과 같은 최근에 생겨난 개념과 시스템들을 획득하는데 목적이 있다.

• 융복합기술연구소 논문집
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• 제6권1호
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• pp.37-41
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• 2016

The serpentine internal passage is located in turbine blade and it shows the variety heat transfer distribution. Especially, the Coriolis force, which is induced by blade rotation, makes different heat transfer distribution of the leading and trailing surfaces of serpentine internal passage. The different heat transfer is one of the reasons why the serpentine cooling passage shows low cooling performance in the rotating condition. So, this study tried to design the advanced the serpentine passage to consideration of the Coriolis force. The design concept of advanced serpentine cooling is maximizing cooling performance using the Coriolis force. So, the flow turns from leading surface to trailing surface in advanced serpentine passage to match the direction of Coriolis force and rotating force. We performed numerical analysis using CFX and compared the existing and advanced serpentine internal passage. This design change is induced the high heat transfer distribution of whole advanced serpentine internal passage surfaces.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 G
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• pp.2986-2988
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• 1999

This paper presents a new concept to implement and to control of tactile reproduction simulator by implementation of compliance emulator system. Compliance emulator system is a kind of levitation system using magnetic force. In the compliance emulator system, a floated plate moves vertically. When an external force is applied to the plate, the system produces a controlled reaction force by using 6 electromagnet. For the control, a LVDT displacement sensor and PD control method is used.

• 한국농공학회지
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• 제15권3호
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• pp.3114-3118
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• 1973

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2017년도 추계학술논문요약집
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• pp.189-190
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• 2017

For the concept design of the device, a tool was made to test the simulated fuel rods and cutting force and the cutting force was measured. When 2-CUT and 3-CUT modules were used, the maximum force in 2-CUT at 12.5 mm/s speed change was $197.5kg_f$ and the maximum force at 3-CUT was $363.2kg_f$. The change of force in 2-CUT rapidly increases from about 1 second, and you can see that there are increase and decrease of the force change from about 5 seconds to 18 seconds, and it was rapidly decreased and the cut was made. The force change in 3-CUT has higher force at about 5 seconds later than 2-CUT at the speed of 12.5 mm/s, and you can see that it has the same tendency afterwards. If you search for the force at adequate speed from this cutting force test, 2-CUT module requires less slitting force than 3-CUT module, and the cutting time for 250 mm at 12.5 mm/s was 21 seconds, which can cut 4 m fuel rod in 5 minutes. But, there are cases of not completely slitting with 2-CUT module, so it is necessary to supplement this in the future through experiments.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1545-1548
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• 1997

A Force-refecting hand controller can provide the kinesthetic information obtained from a slave manipulator to the operator of a teleoperation system. This thesis presents the desgn and the analysis of a 6-degree-of-freedom force-reflecting hand controller using fivebar parallel mechanism. The goal of this thesis is to construct a superior hand controller that can provide large workspace and good force-reflecting ability. The forward kinematics of the fivebar paprallel mechanism has been calculated in real-time using three pin-joint sensors in addition to six actuator position sensors. A force decomposition approach is used to comput the Jacobin. To analyze the characteristics of the fivebar parallel mechanism, it has been compared with the other three parallel mechanisms in terms with workspace and manipulability measure. The force-reflecting hand controller using the fivebar parallel mechanism has been constructed and tested to verify the feasibility of the design concept.

• 제어로봇시스템학회논문지
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• 제5권3호
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• pp.288-296
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• 1999

A force-reflecting hand controller can provide the kinesthetic information obtained from a slave manipulator to the operator of a teleoperation system. The goal is to construct a compact hand controller that can provide large workspace and good force-reflecting capability. This paper presents the design and the analysis of a 6-degree-of-freedom force-reflecting hand controller using fivebar parallel mechanism. The forward kinematics of the fivebar parallel mechanism has been calculated in real-time using three pin-joint sensors in addition to six actuator position sensors. A force decomposition approach is used to compute the Jacobian. To evaluate the characteristics of the fivebar parallel mechanism, it has been compared with the other three parallel mechanisms in terms with workspace and manipulability measure. The hand controller using the fivebar parallel mechanism has been constructed and tested to verify the feasibility of the design concept.