• Title/Summary/Keyword: 가.감속도

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A Study on the Aerodynamic Force Augmentatation Panel for Improving Lift-Drag Characteristics at High Angle of Attack (높은 받음각에서 양항 특성의 향상을 위한 공력 보조 PANEL에 관한 연구)

  • Shin, Dong-Jin;Lee, Bong-Jun
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.2
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    • pp.57-80
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    • 1994
  • 항공기에 사용되는 2차 조종면은 플랩, 탭, 스포일러 등 여러 종류가 있으며 이중 spoiler는 공력제어 기능을 가지고 항공기의 조종성에 영향을 미치는 조종면으로 속도 감속이나 옆놀이 조종용으로 사용된다. 본 연구에서는 비행제어용 spoiler 기능과 고양항력을 얻을 수 있는 새로운 장치인 고양항력 panel에 대한 공력특성 및 비행제어 특성에 대하여 연구하였다. 이러한 고양항력 panel은 재래식인 spoiler가 양력을 감소시키고 항력만 증가시키는 장치인데 반하여 양력과 항력을 동시에 증가 시킬 수 있는 새로운 장치로서 날개의 앞전 윗면에 스팬방향으로 설치하여 슬롯효과를 발생시킴으로써 최대 양력 받음각에서 앞전에서의 박리를 막아 비행기의 착륙시 양력의 급작스러운 감소로 인한 불안정성을 감소시키게 된다. 본 논문에서는 직사각형 날개 및 FA-200모형의 날개위에 고양항력 panel을 설치하여 풍동실험 및 수치계산을 한 결과를 기술하였다. 실험결과 직사각형 날개의 경우 고양항력 panel의 위치는 날개의 앞전에 설치할 경우 고받음각에서 실속지연의 효과와 함께 후방실속의 특성을 향상 시킬 수 있으며, 항력의 증가로 인한 스포일러 효과를 얻을 수 있다. 양항비특성은 고양항력 panel을 날개의 앞전에설치하고, 그폭이 시위의 1/5이고, 붙임각 ${\theta}$$10^{\circ}$, 높이가 시위의 3/20일때 받음각 $18^{\circ}$ 이후에서 우수한 특성을 나타내었다. FA-200 모형의 경우 옆놀이 모멘트계수는 받음각이 작을 때 고양항력 panel의 슬롯간격과 붙임각이 작을수록 커지나 받음각이 커지면 붙임각이 커짐에 따라 증가함을 알 수 있다. 또한 키놀이 모멘트계수는 크게 변화하지 않으나 항력 특성은 고양항력 panel의 붙임각이 증가함에 따라 증가하였다. 고양항력 panel의 붙임각이 큰 범위에서 (${\theta}$ =$10^{\circ}$) 공기력의 증가는 고양항력 panel의 시위가 날개시위의 30%이고 슬롯의 폭이 날개시위의 10%일때 증가하는 결과를 얻을 수 있다.

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Turbojet Engine Control of UAV using Artificial Neural Network PID (인공신경망 PID를 이용한 무인항공기 터보제트 엔진 제어)

  • Kim, Dae-Gi;Hong, Gyo-Young;Ahn, Dong-Man;Hong, Seung-Beom;Jie, Min-Seok
    • Journal of Advanced Navigation Technology
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    • v.18 no.2
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    • pp.107-113
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    • 2014
  • In this paper, controller Propose to prevent compressor surge and improve the transient response of the fuel flow control system of turbojet engine. Turbojet engine controller is designed by applying Artificial Neural Network PID control algorithm and make an inference by applying Artificial Neural Network Error Back Propagation Algorithm. To prevent any surge or a flame out event during the engine acceleration or deceleration, the ANN PID controller effectively controls the fuel flow input of the control system. ANN PID results are used as the fuel flow control inputs to prevent compressor surge and flame-out for turbo-jet engine and the controller is designed to converge to the desired speed quickly and safely. Using MATLAB to perform computer simulations verified the performance of the proposed controller. Response characteristics pursuant to the gain were analyzed by simulation.

Design of PID Type Fuzzy Logic Acceleration Controller for Turbojet Engine Using High-gain Observer (고이득 관측기를 이용한 터보제트 엔진의 PID 퍼지 추론 가속도 제어기 설계)

  • Jie, Min-Seok;Kim, Dae-Gi;Hong, Gyo-Young;Ahn, Dong-Man;Hong, Seung-Beom
    • Journal of Advanced Navigation Technology
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    • v.17 no.1
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    • pp.107-114
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    • 2013
  • In this paper, we propose controller to control the acceleration of unmanned aircraft turbojet engine. The high-gain observer to estimate the rotational speed of compressor is used, and the turbojet engine controller applying fuzzy heuristic techniques and PID control algorithm are designed. fuzzy PID controller produces the flow control input to prevent the surge and flame-out phenomena at the acceleration and deceleration of the turbojet engine. The standard acceleration is set and the fuel flow control is defined by the fuzzy heuristic. Computer simulations are performed using MATLAB in order to verify the performance of the proposed controller.

Kinetic Analysis of Golf Fat Shot (골프 Fat shot에 대한 운동역학적 분석)

  • Sohn, Jee-Hoon
    • The Journal of the Korea Contents Association
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    • v.13 no.10
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    • pp.523-532
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    • 2013
  • When the golf club hits the ground prior to making contact with the golf ball, we define it as 'fat shot'. The aim of this research was to investigate the difference between normal shot and fat shot in golf. Five candidates playing as recreational golfer participated in this research and they were all right-handed people. Time phase between each event, wrist cocking angle, elbow extension-flexion angle, backswing height, pelvis angle, thorax angle, L-GRF, R-GRF, pelvis linear velocity, pelvis angular velocity and COG path were calculated. For statistical analysis the paired T-test was used. An early un-cocking, an early right elbow extension and impact with leaving their weight behind foot were not reasons of fat shot. Backswing height, X-Factor, pelvis angle and thorax rotation angle were not different between normal shot and fat shot. But we could find a pattern of abrupt pelvic movement and weight shift to target direction just before impact in case of fat shot. In addition fat shot showed time-delayed and small value of pelvis linear velocity pattern to upward during downswing phase as against normal shot.

A Study on the Drive-less Operating Technology using Communication Based Train Control (무선통신기반 열차제어에 의한 무인운전기술에 대한 연구)

  • Jeong, Rag-Gyo;Kim, Baek-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.1
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    • pp.67-72
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    • 2010
  • In this paper, we verify the driverless operation possibility of MBS, which could overcome the defects of conventional track-circuit-based FBS, such as additional needs of maintenance and others problems according to short-circuit sensibility and, and which could allow the minimal interval between trains. With MBS, we can expect the reduction of headway, then the increase of transportation demand, and the protection of unnecessary speed variation because it allows the real time detection of train position from central office, and direct transmission of data between preceding trains and the following ones. In addition, it is possible to reduce the number of wayside-equipment substantially, to improve the passenger service, and to the achieve the positive economic effects by comfortable ride.

Finite Element Analysis for the Safety Assessment of Take-out Robot (취출로봇의 안전성 평가를 위한 유한요소해석)

  • Hong, Hee-Rok;Lee, Joon-Seong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.3
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    • pp.1241-1246
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    • 2014
  • Take-out robots used for handling of the plastic parts manufactured with the injection mold are usually the gantry type that consists of long and thin links. In this study, we want to evaluate the safety of the take-out Robot structure through finite element analysis. The take-out Robot is automated robot to transport from one location to another in the molded article. The take-out Robot structure has a 380 kilogram weight, a 1300mm width, a 670.5mm depth and a 670mm height. It confirms the equivalent stress and the deformation of the load and its own weight through weight analysis. It looks for the natural frequency of the take-out robot through modal analysis. It confirms the acceleration, the normal stress and the deformation about the natural frequency of the take-out robot through response analysis. Also It repeats the analysis by changing the structure of the take-out robot, to confirm the results and it is determined whether the safety of the structure. These analysis results are effectively used to reduce the vibration of the take-out robot.

A Research for Improvement of WIM System by Abnormal Driving Patterns Analysis (비정상 주행패턴 분석을 통한 WIM 시스템 개선 연구)

  • Park, Je-U;Kim, Young-Back;Chung, Kyung-Ho;Ahn, Kwang-Seon
    • Journal of Internet Computing and Services
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    • v.11 no.4
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    • pp.59-72
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    • 2010
  • WIM(Weigh-In-Motion) is the system measuring the weight of the vehicle with a high-speed. In the existing WIM system, vehicle weight is measured based on the constant speed and the error ratio has 10%. However, because of measuring the driving pattern, that is abnormal driving pattern which is like the acceleration and down-shift of the drivers, it has the error ratio which is bigger than the real. In order to it reduces the error ratio of WIM system, the improved WIM system needs to find the abnormal driving pattern. In order to reducing the error ratio of these WIM systems, the improved WIM system can find abnormal driving patterns. In this paper, the improved WIM system which analyzes the abnormality driving pattern influencing on the error ratio of WIM system of an existing and minimizes the error span is designed. The improved WIM system has the multi step loop structure of adding the loop sensor to an existing system. In addition, the measure function defined as an intrinsic is improved and the weight measured by the abnormal driving pattern is amended. The analysis of experiment result improved WIM system can know the fact that the error span reduces by 8% less than in the existing the maximum average sampling error 22.98%.

A Case Study on a Way of Improving the Grand Alliance Container Service Route by Incorporating Dedicated Feeders - Focusing on 'Far East-West Coast of North America' Route - (전용 피더 서비스 연계를 통한 Grand Alliance 컨테이너 서비스 항로의 운영 개선에 관한 사례 연구: '극동-북미서안' 컨테이너 서비스 항로를 중심으로)

  • Kim, Woo-Jin;Shin, Jeong-Hoon;Chang, Myung-Hee
    • Journal of Navigation and Port Research
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    • v.36 no.5
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    • pp.409-418
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    • 2012
  • Amid global economic crisis and skyrocketing oil prices, container shipping companies have raised a sustained series of efforts to reduce vessel operating costs. Under these circumstances, the Grand Alliance has decided to install the dedicated feeder instead of additional vessels in the CCX(Central China Express) and the NCE(North China Express) route. In other words, a vessel in a trunk route is transshiped by a dedicated feeder vessel in Busan port that is a transshipment port, rather than calling at Northen China port. In this study, the actual operating data of Grand Alliance container services were analyzed to determine the economic effect of transshipment through a dedicated feeder service. In this way, the Grand Alliance are saving vessel operating expenses in 'NCE' and 'CCX' routes, making the slow steaming of vessels possible in these trunk routes.

A Study on Improving Driving Stability System by Yaw Moment Control (요우모멘트를 통한 주행안정성 향상 제어 알고리즘에 관한 연구)

  • Park Jung-hyen;Kim Soon-ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.2
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    • pp.392-397
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    • 2006
  • This paper proposed yaw moment control scheme using braking and active rear wheel steering for improving driving stability especially in high speed driving. Its characteristics the unified chassis control system of two equipment that 4WS(4 Wheel Steering) and ESP(Electronic Stability Program). in this study the performance of the vehicle was compared each equipment. And conventional ABS and TCS can only possible to control the longitudinal movement of braking equipment and drive which can only available to control of longitudinal direction. There after new braking system ESP was developed, which controls both of longitudinal and lateral, with adding of the function of controlling Active Yaw Moment. On this paper, we show about not only designing of improved braking and steering system through establishing of the integrated control system design of 4WS and ESP but also designing of the system contribute to precautious for advanced vehicle stability problem.

A Study on Improving Driving Stability System in Slalom and Emergency Case (급선회반복 및 위급상황에서의 주행안정성 시스템에 관한 연구)

  • Park Jung-hyen;Kim Soon-ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.8
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    • pp.1716-1721
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    • 2005
  • Conventionally, 2WS is used for vehicle sleeting, which can only steering front wheel. In case of trying to high speed slalom or emergency through this kind of vehicle equipped 2WS, it may occur much of side slip angle. On the other hand, 4WS makes decreasing of side slip angle, outstandingly, so it is possible to support vehicle movement stable. And conventional ABS and TCS can only possible control the longitudinal movement of braking equipment and drive which can only availab to control of longitudinal direction. There after new braking system ESP was developed, which controls both of longitudinal and lateral, with adding of the function of controlling Active Yaw Moment. On this paper, we show about not only designing of improed braking and steering system through establishing of the integrated control system design of 4WS and ESP but also designing of the system contribute to precautious for advanced vehicle stability problem.