• Title/Summary/Keyword: Dynamic Model

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Lateral Dynamic Model of an All-Wheel Steered Articulated Vehicle for Guidance Control (전차륜조향 굴절차량의 안내제어를 위한 횡방향 동역학 모델)

  • Yun, Kyoung-Han;Kim, Young-Chol;Min, Kyung-Deuk;Byun, Yeun-Sub
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.6
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    • pp.1229-1238
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    • 2011
  • This paper deals with the lateral dynamic model of an all-wheel steered articulated vehicle to design a guidance controller. Nonlinear dynamic model of articulated vehicle is developed by complementing the model about the BRT system of California PATH in U. S. A. and the Phileas system of the APTS in Netherlands. Linear lateral dynamic model has been derived from the nonlinear dynamic model under some assumptions associated with the driving conditions. To design a guidance controller, we derive a transfer function that is steering angle as input and lateral acceleration as output from the linear lateral dynamic model by applying the parameter of vehicle that is developed by Korea Railroad Research Institute. To validate the dynamic model, nonlinear dynamic model has been compared with a vehicle model that has been programmed in ADAMS, and linear dynamic model has been compared with a nonlinear dynamic model under sime assumptions.

Dynamic Model for Compliant Mechanism with Long Flexure Hinges (긴 유연힌지를 갖는 컴플라이언스 메커니즘의 동역학 모델)

  • Choi Kee-Bong
    • Journal of the Korean Society for Precision Engineering
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    • v.22 no.3
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    • pp.61-67
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    • 2005
  • A dynamic model for flexure hinge-based compliant mechanisms is derived. The dynamic model of the previous works do not well describe the behaviors of rigid bodies in the compliant mechanism when the length of the flexure hinge is long. In this study, the effect on the length of the flexure hinge is pointed out and then the dynamic model is derived to overcome the length effect. For verification, modal analyses are carried out using the proposed dynamic model and FEM (Finite Element Method). Finally they are compared by the terms of modal frequency. As the result, the proposed dynamic model can be used in design and analysis of the compliant mechanism.

Dynamic Model Identification of Quadrotor UAV based on Frequency-Domain Approach (주파수 영역 기반 쿼드로터 무인기 운동 모델 식별)

  • Jung, Sunggoo;Kim, Sung-Yug;Jung, Yeundeuk;Kim, Eung-Tai
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.23 no.4
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    • pp.22-29
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    • 2015
  • Quadrotor is widely used in variable application nowadays. Due to its inherent unstable characteristics, control system to augment the stability is essential for quadrotor operation. To design control system and verify its performance through simulation, accurate dynamic model is required. Quadrotor dynamic model is simply compared with conventional rotorcraft such as helicopter. However, the accurate dynamic model of quadrotor is not easy to develop because of the highly correlated aerodynamic effect of each rotor. In this paper, quadrotor dynamic model is identified from the flight data using frequency domain approach. Flight test of quadrotor is performed in closed loop configuration with stability augmentation system included. Frequency sweep input is applied in each of lateral, longitudinal, yaw and heave axis separately. The bare dynamic model is identified from the flight data of quadrotor responses and thrust measurement through Pulse Width Modulation(PWM) data. The frequency responses of identified model match well with those of flight data, and time responses of identified model for doublet input in each axis are also shown to agree with flight data.

Transient Simulation of CMOS Breakdown characteristics based on Hydro Dynamic Model (Hydro Dynamic Model을 이용한 CMOS의 파괴특성의 Transient Simulation해석)

  • Choi, Won-Cheol
    • Journal of the Korean Society of Industry Convergence
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    • v.5 no.1
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    • pp.39-43
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    • 2002
  • In present much CMOS devices used in VLSI circuit and Logic circuit. With increasing a number of device in VLSI, the confidence becomes more serious. This paper describe the mechanism of breakdown on CMOS, especially n-MOS, based on Hydro Dynamic model with device self-heating. Additionally, illustrate the CMOS latch-up characteristics on simplified device structure on this paper.

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Dynamic Model of a Long-term Water Demand Using System Dynamics (시스템 다이나믹스를 이용한 도시 물수요 장기 예측의 동적 모델 연구)

  • Lee, Sangeun;Choi, Dongjin;Park, Heekyungh
    • Journal of Korean Society of Water and Wastewater
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    • v.21 no.1
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    • pp.75-82
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    • 2007
  • When one forecasts urban water demand in a long-term, multivariate model can give more benefits than per capita requirement model. However, the former has shortcomings in that statistically high explanatory power cannot be obtained well, and change in customer behavior cannot be considered. If the past water consumption effects the future water demand, dynamic model may describe real water consumption data better than static model, i.e. the existing multivariate model. On these grounds, this study built dynamic model using system dynamics. From a case study in Seoul and Busan city, dynamic model was expected to forecast water demand more descriptively and reliably.

Realization of Differential Drive Wheeled Mobile Robot Dynamic Modeling Using Newton's Equilibrium law (뉴튼의 평행법칙을 이용한 차동구동 이동로봇의 동력학 모델링 구현)

  • Chung, Yong-Oug;Chung, Ku-Seob
    • The Journal of Korea Robotics Society
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    • v.5 no.4
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    • pp.349-358
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    • 2010
  • We presents a dynamic modeling of 4-wheel 2-DOF. WMR. The classic dynamic model utilizes a greatly simplified wheel motion representation and using of a simplified dynamic model confronts with a problem for accurate position control of wheeled mobile robot. In this paper, we treats the dynamic model for describes relationship between the wheel actuator force/torque and WMR motion through the use of Newton's equilibrium laws. To calculate the WMR position in real time, we introduced the Dead-Reckoning algorithms and the simulation result show that the proposed dynamic model is useful. We can be easily extend the proposed WMR model to mobile robot of similar type and this type of methodology is useful to analyze, design and control any kinds of rolling robots.

Design of Vacuum Circuit Breaker Based on Dynamic Model (동적모델에 기반한 진공 회로차단기의 설계)

  • 권병희;안길영
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • pp.1418-1421
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    • 2003
  • The Vacuum circuit breaker is a kind of power circuit breaker and protect electric devices from over-current. In this paper we built a dynamic model of VCB driving mechanism using ADAMS. The development of the new circuit breaker with less energy and more compactable mechanism is focused. Through the dynamic model, the concept design of the new circuit breaker with less energy and more compactable mechanism is proposed, and then the detailed design is carried out through the design process based on the dynamic model.

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A Study on the Comparison of Freud's Dynamic Model and Frederick J. Kiesler's Architectural Thoughts (프로이트의 역동적 모델과 프레데릭 J. 키슬러의 건축사상 비교 연구)

  • Lee, Jae-In
    • Journal of the Architectural Institute of Korea Planning & Design
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    • v.30 no.8
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    • pp.173-180
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    • 2014
  • This study compared Frederick J. Kiesler's endless and correalism with Freud's dynamic model of psychoanalysis and, based on the comparison results, analyzed Kiesler's works, inferring new architectural concepts from a psychoanalytical viewpoint. In addition, the study found the interface between psychoanalysis and modern architecture based on the architectural concept drawn here, establishing the basis of combining the two fields. The results of the study are as follows. First, the comparison of dynamic model as an agency and correalism found that human environment can be comparable to a conscious ego, and natural environment and artificial environment to unconscious id and super-ego. The space which serves as a medium connecting the three environments can be seen as an agency that connects psychological factors of dynamic model. When the space concept of endless is compared here, the three environments can be understood as spaces that circulate without stopping like agencies of psychological factors in dynamic model. Second, in Kiesler's early works, his concept of endless was tilted towards morphological sides as continuous tension of shell structures. However, as he created several works, he developed the concept of section, and visual continuity evolved into spatial continuity. In this process, segment serves as a subject of spatial medium as an agency of each space. Third, in the final version of Kiesler's Endless House, segment developed as a symbolic space of seclusion. The space finalizes the concept of endless by completing a whole spatial flow through expanding the concept of section. This can be comparable to Freud's theoretical development that shows the psychological factors of ego, super-ego, and id have conscious and unconscious flows as agencies by completing dynamic model through the instruction of super-ego in Constructivist model.

Singularity-Free Dynamic Modeling Including Wheel Dynamics for an Omni-Directional Mobile Robot with Three Caster Wheels

  • Chung, Jae-Heon;Yi, Byung-Ju;Kim, Whee-Kuk;Han, Seog-Young
    • International Journal of Control, Automation, and Systems
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    • v.6 no.1
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    • pp.86-100
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    • 2008
  • Most of the previously employed dynamic modeling approaches, including Natural Orthogonal Complement Algorithm, have limitations on their application to the mobile robot, specifically at singular configurations. Also, in their dynamic modeling of mobile robots, wheel dynamics is usually ignored assuming that its dynamic effect is negligibly small. As a remedy for this, a singularity-free operational space dynamic modeling approach based on Lagrange's form of the D' Alembert principle is proposed, and the singularity-free characteristic of the proposed dynamic modeling is discussed in the process of analytical derivation of the proposed dynamic model. Then an accurate dynamic model taking into account the wheel dynamics of the omni-directional mobile robot is derived, and through simulation it is manifested that the effect of the wheel dynamics on the whole dynamic model of the mobile robot may not be negligible, but rather in some cases it is significantly large, possibly affecting the operational performances of dynamic model-based control algorithms. Lastly, the importance of its accurate dynamic model is further illustrated through impulse analysis and its simulation for the mobile robot.

Prediction of Surface Topography by Dynamic Model in High Speed End Milling (고속 엔드밀 가공시 동적 모델에 의한 표면형상 예측)

  • Lee, Gi-Yong;Ha, Geon-Ho;Gang, Myeong-Chang;Lee, Deuk-U;Kim, Jeong-Seok
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.24 no.7
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    • pp.1681-1688
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    • 2000
  • A dynamic model for the prediction of surface topography in high speed end milling process is developed. In this model the effect of tool runout, tool deflection and spindle vibration were taken in to account. An equivalent diameter of end mill is obtained by finite element method and tool deflection experiment. A modal parameter of machine tool is extracted by using frequency response function. The tool deflection, spindle vibration chip thickness and cutting force were calculated in dynamic cutting condition. The tooth pass is calculated at the current angular position for each point of contact between the tool and the workpiece. The new dynamic model for surface predition are compared with several investigated model. It is shown that new dynamic model is more effective to predict surface topography than other suggested models. In high speed end milling, the tool vibration has more effect on surface topography than the tool deflection.