• 한국산학기술학회논문지
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• 제15권8호
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• pp.4742-4748
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• 2014

전북 익산시 R회사에서 기 개발된 세미오토 클러치는 수동클러치 차량의 기어 변속시 클러치 페달을 밟아야하는 불편함을 해소하고자 만들어진 장치로써 클러치 페달을 밟지 않고, 운전자가 기어봉에 위치한 스위치 조작만으로도 클러치 동작을 제어할 수 있다. 차량의 변속과정에서 클러치 동작을 제어하기 위해 센서를 설치하여 차량정보를 수집하여 제어하였다. 그러나, 센서 기반의 제어기는 열악한 운전조건에서 고장 원인이 되고 있으며, 차량에 설치하고 보수하는 과정에서 시간소요가 과다하여 많은 불편을 가지고 있었다. 이를 위해 본 연구에서는 차량의 ECU와 CAN통신을 통해 차량의 주행정보를 수집하여 제어하고, 공압 액추에이터로 클러치를 동작시키는 세미오토 클러치를 개발하였다. 개발된 공압 액추에이터의 정상적인 동작을 위해서는 최소 3bar이상이 요구되었다.

• 한국해양공학회지
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• 제19권5호
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• pp.16-25
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• 2005

The effect of vertical riser support system on the dynamic behaviour of a classical spar platform is investigated. Spar platform generally uses buoyancy-can riser support system, but as water depth gets deeper the alternative riser support system is required due to safety and cost issues. The alternative riser support system is to hang risers off the spar platform using pneumatic cylinders rather than the buoyancy-can. The existing numerical model for hull/mooring/riser coupled dynamics analysis treats riser as an elastic rod truncated at the keel (truncated riser model), thus, in this model, the effect of riser support system can not be modeled correctly. Due to this reason, the truncated riser model tends to overestimate the spar pitch and heave motion. To evaluate more realistic global spar motion, mechanical coupling among risers, guide frames and support cylinders inside of spar moon-pool should be modeled. In the newly developed model, the risers are extended through the moon-pool by using nonlinear finite element methods with realistic boundary condition at multiple guide frames. In the simulation, the vertical tension from pneumatic cylinders is modeled by using ideal-gas equation and the vertical tension from buoyancy-cans is modeled as constant top tension. The different dynamic characteristics between buoyancy-can riser support system and pneumatic riser support system are extensively studied. The alternative riser support system tends to increase spar heave motion and needs damper system to reduce the spar heave motion.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2002년도 춘계학술대회 논문집
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• pp.440-445
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• 2002

공압쿠션실린더(${\psi}80{\times}500^{st}$)의 쿠션장치인 쿠션슬리브(${\psi}20{\times}28^{st}$) 4종(Model #a, Model #b, Model #c, Model #d) 모델을 제작하여 수직하강하는 실린더에 각각 장착한 후, 각 모델에 따라 압력과 부하 특성을 비교하였다. 동일한 실험조건인 공급압력($5kg_{f}/$\textrm{cm}^2$)과 부하하중($70kg_{f}$)에서 각 모델별 실험을 실행하였다. 각 모델별 실험에서, Model #c의 쿠션슬리브인 경우가 가장 적합한 형상임을 알 수 있었다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1993년도 한국자동제어학술회의논문집(국제학술편); Seoul National University, Seoul; 20-22 Oct. 1993
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• pp.298-301
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• 1993

In pneumatic systems the temperature changes during operation owing to air compression or expansion, friction of air movement and friction between solid interface. The temperature change usually ha undesirable influence on process. To attain higher quality of pneumatics, studies in thermo-fluid dynamics is needed. This paper presents experimental results anti theoretical analysis on the temperature change by air charge and discharge to cylinders, which has no piston yet. The temperature increase by charge shows a strong, dependence on axial location along the cylinder, which is proved in theoretical analysis. The temperature decreases by discharge shows rather uniform in the cylinder, which is also proved by theory.

• 대한기계학회논문집A
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• 제22권2호
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• pp.467-475
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• 1998

The Six Degree-of-Freedom manipulators are generally operated by linear actuators which are hydraulic cylinder, pneumatic cylinder, ball-screw. But these actuators are not adequate to have a wide work-space, and furthermore some of them have a self-locking property. Therfore, we have designed a new manipulator which fully overcomes these demerits. The new manipulating system consists of 6 DC-motors to generate operation forces and 6 position transducers to feedback displacement signals. This paper presents an overview of the design and characteristics of 6 Degree-of-Freedom force feedback manipulators for vitual reality implementation. we can operate Six Degree-of-Freedom manipulator with six motors and six potentiometers.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1993년도 추계학술대회 논문집
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• pp.402-405
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• 1993

This paper presents design.dynamic modeling and control issues of a novel type of an ER valve-cylinder system incorporating with an electro-rheological(ER) fluid. The yield stress of the ER fluid to be employed to the proposed system is evaluated as a function of applied electric fields. The design and manufacturing process of the ER valve which features fast system response and simple mechanism are undertaken on the basis of model parameters. The governing equation for the hydraulic and pneumatic model is constructed by incorporation with the field-dependent Bingham behavior of the ER fluid. An effective neuro controller is proposed to realize an accurate position control.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.132.5-132
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• 2001

In teleoperation field robotic system such as hydraulically actuated robotic excavator, the maneuverability and convenience is the most important part in the operation of robotic excavator. Particularly the force information is important in dealing with digging and leveling operation in the teleoperated excavator. Excavators are also subject to a wide variation of soil-tool interaction forces. This paper presents a new force reflecting joystick in a velocity-force type bilateral teleoperation system. The master system is electrical joystick and the slave system is hydraulically actuated cylinder with linear position sensor. Particularly Pneumatic motor is used newly in the master joystick for force reflection and the information of the pressure of salve cylinder is measured and utilized as the force feedback signal. Also force-reflection gain greatly affects the ...

• 한국자동차공학회논문집
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• 제14권6호
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• pp.160-170
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• 2006

If hydraulic pump controlled by mechanical type regulator has more than one control function, the construction of regulator will be very complicated and control performance falls drastically. It is difficult to have more than one control function for hydraulic pump controlled by electronic type hydraulic valve due to the inconsistency of controllers. This paper proposes a multi-function control technique which controls continuously flow, pressure and power by using EPPR(Electronic Proportional Pressure Reducing) valve in swash plate type axial piston pump. Nonlinear mathematical model is developed from the continuity equation for the pressurized control volume and the torque balance for the swash plate motion. To simplify the model we make the linear state equation by differentiating the nonlinear model. A reaction spring is installed in servo cylinder to secure the stability of the control system. We analyze the stability and disturbance by using the state variable model. Finally, we review the control performances of flow, pressure and power by tests using PID controller.

• 동력기계공학회지
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• 제19권1호
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• pp.76-82
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• 2015

An analysis model is developed using a commercial software 'simulationX' for designing hydraulic-pneumatic system of heave compensator for offshore drilling operations. Reliability verification of the analysis model for the test equipment of 1/5 scale compensator was conducted by comparing test results and simulation results. An analysis of full scale heave compensator is developed on the basis of verified a model. Then, the results of simulation were analyzed to obtain following conclusion. The displacement of crown block about excitation input amplitude (${\pm}3,000mm$) of the steward platform using a 'simulationX' is attenuated under ${\pm}35mm$, and the compensation rate is 98.7%. In this study, goal of a compensation rate is more than 95%. The previously results are satisfied with the objectives of compensation rate.

• 한국산학기술학회논문지
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• 제14권12호
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• pp.6090-6097
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• 2013

본 연구의 목적은 실감나는 운전 환경을 제공하는 공기압 구동식 드라이빙 시뮬레이터 개발에 있다. 드라이빙 시뮬레이터의 모션 플랫폼은 운전자에게 실제 차량의 사실적인 느낌을 주는 메카트로닉스 장비이다. 모션 플랫폼의 비용은 드라이빙 시뮬레이터를 개발하는데 가장 큰 부분을 차지한다. 저비용으로 모션 플랫폼을 개발하기 위하여 6개의 공압 실린더로 구성된 스튜어트 플랫폼 형태를 기반으로 모션 플랫폼을 자체 제작하였다. 스튜어트 플랫폼은 조이스틱의 작동신호에 대한 응답으로 만족할 만한 추종성능을 보여주었다. 상용의 레이싱 게임 소프트웨어 중의 하나인 rFactor를 이용하여 드라이빙 시뮬레이터의 가능성을 확인하였다.