• Title/Summary/Keyword: Design stabilization

Search Result 700, Processing Time 0.024 seconds

Adaptive Variable Structure Control of Container Cranes with Unknown Payload and Friction (미지의 부하와 마찰을 갖는 컨테이너 크레인의 적응 가변구조제어)

  • Baek, Woon-Bo;Lim, Joong-Seon
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.20 no.10
    • /
    • pp.1008-1013
    • /
    • 2014
  • This paper introduces an adaptive anti-sway tracking control algorithm for container cranes with unknown payloads and friction between the trolley and the rail. If the friction effects in the system can be modeled, there is an improved potential to design controllers that can cancel these effects. The proposed control improves the sway suppressing and the positioning capabilities of the trolley and hoisting against uncertain payload and friction. The variable structure controls are first designed based on a class of feedback linearization methods for the stabilization of the under-actuated sway dynamics. The adaptation mechanism are then designed with parameter estimation of unknown payload and friction compensation for the trolley and hoisting, based on Lyapunov stability methods for the accurate positioning and fast attenuation of trolley oscillation due to frictions in the vicinity of the target position. The asymptotic stability of the overall closed-loop system is assured irrespective of variations of rope length. Simulations are shown under various frictions and external winds in the case of no priori information of payload mass.

Removal of Debris Blocking an Entryway: Inverse Kinematic Control and Balancing Controller Design for Humanoid (휴머노이드 로봇의 입구 통로를 막고 있는 잔해 제거를 위한 역 기구학 제어와 자세 제어기 설계)

  • Lee, In-Ho;Kim, Inhyeok;Oh, Jun-Ho
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.20 no.10
    • /
    • pp.1063-1066
    • /
    • 2014
  • The humanoid robot, DRC-HUBO is developed from the KHR (KAIST Humanoid Robot) series to meet the requirements of the DARPA Robotics Challenge. DARPA Robotics Challenge was a competition to develop semi-autonomous humanoid robot so that dispatched in dangerous environments in place of humans like the Fukushima nuclear accident. In this paper, we introduce DRCH-UBO briefly and a methodology to remove debris blocking an entryway. The methodology includes inverse kinematics for DRC-HUBO and stabilization controller based on ZMP. Proposed inverse kinematics is robust, and pelvis-related tasks improve the manipulability and workspace of the arms. The controller improves the damping characteristic of the system and mitigates the instability during removal of debris. For given position and orientation of the debris, DRC-HUBO generates motion to reach the debris and lift up while stabilizing itself. Many experimental results verify our proposed methodology.

Technical Review and Analysis of Ramjet/Scramjet Technology II. Scramjet and Combined Cycle Engine (램제트/스크램제트의 기술동향과 기술분석 II. 스크램제트 및 복합엔진)

  • Sung Hong-Gye;Yoon Hyun-Gull
    • Journal of the Korean Society of Propulsion Engineers
    • /
    • v.10 no.2
    • /
    • pp.115-128
    • /
    • 2006
  • A technical analysis of current scramjet and combined-cycle engine is presented. Substantial research has been pursued to characterize the operation mechanism of scramjet propulsion, especially in the areas of flame stabilization and system integration, dramatically over the years in support of both military and space access application. Major technology that had significant impact on the maturation of scramjet propulsion technology are dual combustion ramjet, dual mode ramjet, and combined cycle engine to cover a typical wide rage of flight, up to flight Mach number 10. Notable are the fundamental and practical techniques, for instance, scram propulsion itself, thermal relaxation and protection using endothermic fuel and/or CSiC composit materials, and design/manufacture of movable intake and nozzle, to realize high speed propulsion system in near future.

A Decentralized Control Technique for Experimental Nonlinear Helicopter Systems (헬리콥터 시스템의 퍼지 분산 제어기 설계)

  • Kim, Moon-Hwan;Park, Jin-Bae;Lee, Ho-Jae;Cha, Dae-Bum;Joo, Young-Hoon
    • Journal of the Korean Institute of Intelligent Systems
    • /
    • v.12 no.1
    • /
    • pp.80-84
    • /
    • 2002
  • This paper proposes a decentralized control technique for 2-dimensional experimental helicopter systems. The decentralized control technique is especially suitable in large-scale control systems. We derive the stabilization condition for the interconnected Takagi-Sugeno (TS) fuzzy system using the rigorous tool-Lyapunov stability criterion and formulate the controller design condition in terms of linear matrix inequality (LMI). To demonstrate the feasibility of the proposed method, we include the experiment result as well as a computer simulation one, which strongly convinces us the applicability to the industry.

Effects of a Strengthening Program for Lower Back in Older Women with Chronic Low Back Pain (만성요통 여성노인에 대한 요부강화 프로그램의 효과)

  • Hyoung, Hee-Kyoung
    • Journal of Korean Academy of Nursing
    • /
    • v.38 no.6
    • /
    • pp.902-913
    • /
    • 2008
  • Purpose: The purpose of this study was to identify effects of a strengthening program for the lower back in older women with chronic low back pain. Methods: The research design was a nonequivalent control group pretest-posttest experiment. The experimental group consisted of 16 older women and the control group, 14, all of whom had experienced low back pain for at least 3 months. The strengthening program for the lower back included lumbar stabilization exercises and education on pain management in daily living. For an 8 week period, exercises were done 3 days a week and on one day education was also given. Results: Pain and disability scores decreased significantly in the experimental group compared to the control group. Flexibility, life satisfaction and lumbar muscle strength scores increased significantly in the experimental group compared to the control group. Conclusion: Low back pain and disability can be relieved, and flexibility, muscle strength, and life satisfaction increased through a program to strengthen the lower back. It is suggested that a program to strengthen the lower back would be an effective nursing intervention for older women with low back pain.

Structure optimization of neural network using co-evolution (공진화를 이용한 신경회로망의 구조 최적화)

  • 전효병;김대준;심귀보
    • Journal of the Korean Institute of Telematics and Electronics S
    • /
    • v.35S no.4
    • /
    • pp.67-75
    • /
    • 1998
  • In general, Evoluationary Algorithm(EAs) are refered to as methods of population-based optimization. And EAs are considered as very efficient methods of optimal sytem design because they can provice much opportunity for obtaining the global optimal solution. This paper presents a co-evolution scheme of artifical neural networks, which has two different, still cooperatively working, populations, called as a host popuation and a parasite population, respectively. Using the conventional generatic algorithm the host population is evolved in the given environment, and the parastie population composed of schemata is evolved to find useful schema for the host population. the structure of artificial neural network is a diagonal recurrent neural netork which has self-feedback loops only in its hidden nodes. To find optimal neural networks we should take into account the structure of the neural network as well as the adaptive parameters, weight of neurons. So we use the genetic algorithm that searches the structure of the neural network by the co-evolution mechanism, and for the weights learning we adopted the evolutionary stategies. As a results of co-evolution we will find the optimal structure of the neural network in a short time with a small population. The validity and effectiveness of the proposed method are inspected by applying it to the stabilization and position control of the invered-pendulum system. And we will show that the result of co-evolution is better than that of the conventioal genetic algorithm.

  • PDF

A Design of Wide band Dual Folded Microstrip Antennas (광대역 이중 폴디드 마이크로스트립 안테나 설계)

  • 이현진;임영석
    • Journal of the Institute of Electronics Engineers of Korea TC
    • /
    • v.41 no.7
    • /
    • pp.75-79
    • /
    • 2004
  • In this paper, a single plane wide band microstrip antenna for integrated circuit as MMIC and LTCC is designed and fabricated. A new configuration for a wide band microstrip antenna with omni-directional pattern is proposed. This antenna consists of two rectangular folded dipoles, which are fed by a coplanar waveguide(CPW). It was effected stabilization ground that a signal plane of CPW feed have been limited ground plane. Therefore, a ground plane of folded structure should be extended outside folded antenna in this research. The characteristics of the proposed antenna were analyzed by using an FDTD methods. The return loss and radiation patterns were simulated and measured. The proposed antenna is get 120MHz bandwidth of PCS band and 250MHz bandwidth of IMT2000 band, used ISM band.

The Development of Balancing Machine Using Hall Effect Sensor (홀 이펙트 센서를 이용한 밸런싱 머신 개발)

  • Jang, In-Hun;Nam, Won-Ki;Oh, Se-Hoon;Sim, Kwee-Bo
    • Journal of the Korean Institute of Intelligent Systems
    • /
    • v.16 no.2
    • /
    • pp.209-214
    • /
    • 2006
  • The eccentricity of the rotor causes a rotary machine to unbalance and the balancing to correct or compensate this is very important not only for dust-proof and anti -noise design but also for stabilization and durability of the rotary machine. In this paper, for developing the balancing machine to find and compensate such eccentricity, we will propose new way of measuring eccentricity using hall effect sensor that is different from the way in a conventional balancing machine. And we will show that it is possible to make balancing machine more compactly and cheaply by experiment results using hall effect sensor to measure eccentricity. Moreover we try to control and monitor the balancing machine by personal computer through serial communication.

Design of Remote Data Collection System using Orbcomm Satellite Communication (오브컴 위성 통신을 이용한 원격지 데이터 수집 시스템 설계)

  • Heo, Min;Jung, Sung-Hun;Mo, Soo-Jong;Lim, Jae-Hong
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • v.9 no.1
    • /
    • pp.122-125
    • /
    • 2005
  • Data collection system is now widely used. This system is divided by embedded system and communication module. And data collection system in the remote area is using Satellite communication. So, data collection system is complicated and expensive. This paper proposes stabilization and cheapness of remote data collection system in dusty. The system can be composed simply through third party Satellite Communication programming of terminal including embedded system. Finally, collected data is transmitted to multi-user through web agent.

  • PDF

A Study on the brightness distribution which it follows in sheet Variation (시트 변화에 따른 휘도 분포에 관한 연구)

  • Kim, Soo-Yong;Jee, Suk-Kun
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • v.9 no.2
    • /
    • pp.906-910
    • /
    • 2005
  • In this paper, comparing and analyzing the distribution of High brightness as domestic lamps and Japanese products go thinner and lighter, we setting an effective composition. standard. By comparing and analyzing the feature, brightness, chromaticity and uniformity of domestic LGPs and Japanese products, early home-manufacturing and stabilization in home-manufacturing are possible. By comparing and analyzing the distribution of brightness as sariheets are ved, we can design an ideal sheet composition.

  • PDF