• Title/Summary/Keyword: law & system

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A Stable Model Reference Adaptive Control with a Generalized Adaptive Law (일반화된 적응법칙을 사용한 안정한 기준모델 적응제어)

  • 이호진;최계근
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.26 no.8
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    • pp.1167-1177
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    • 1989
  • In this paper, a generalized adaptive law is proposed which uses a rational function type operator for parameter adjustment. To satisfy the passivity condition of the adaptation block, we introduce a constant feedback gain into the adaptation block. This adaptation scheme is applied to the model reference adaptive control of a continuous-time, linear time-invariant, minimum-phase system whose relative degree is 1. We prove the asymptotic stability of the output error of this adaptive system by hyperstability method. It is shown that by digital computer simulations this law can give a better output error transient response in some cases than the conventional gradient adaptive law. And the output error responses for the several types of the proposed adaptation law are examined in the presence of a kind of unmodeled dynamics.

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Attitude Maneuver Control of Flexible Spacecraft by Observer-based Tracking Control

  • Hyochoong Bang;Oh, Choong-Seok
    • Journal of Mechanical Science and Technology
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    • v.18 no.1
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    • pp.122-131
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    • 2004
  • A constraint equation-based control law design for large angle attitude maneuvers of flexible spacecraft is addressed in this paper The tip displacement of the flexible spacecraft model is prescribed in the form of a constraint equation. The controller design is attempted in the way that the constraint equation is satisfied throughout the maneuver. The constraint equation leads to a two-point boundary value problem which needs backward and forward solution techniques to satisfy terminal constraints. An observer-based tracking control law takes the constraint equation as the input to the dynamic observer. The observer state is used in conjunction with the state feedback control law to have the actual system follow the observer dynamics. The observer-based tracking control law eventually turns into a stabilized system with inherent nature of robustness and disturbance rejection in LQR type control laws.

Constitutive law for wedge-tendon gripping interface in anchorage device - numerical modeling and parameters identification

  • Marceau, D.;Fafard, M.;Bastien, J.
    • Structural Engineering and Mechanics
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    • v.15 no.6
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    • pp.609-628
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    • 2003
  • Mechanical anchorage devices are generally tested in the laboratory and may be analyzed using the finite element method. These devices are composed of many components interacting through diverse contact interfaces. Generally, a Coulomb friction law is sufficient to take into account friction between smooth surfaces. However, in the case of mechanical anchorages, a gripping system, named herein the wedge-tendon system, is used to anchor the prestressing tendon. The wedge inner surface is made of a series of triangular notches designed to grip the tendon. In this particular case, the Coulomb law is not adapted to simulate the contact interface. The present paper deals with a new constitutive contact/gripping law to simulate the gripping effect. A parameter identification procedure, based on experimental results as well as on a finite element/neural network approach, is presented. It is demonstrated that all parameters have been selected in a satisfactory way and that the proposed constitutive law is well adapted to simulate the wedge gripping effect taking place in a mechanical anchorage device.

Integrated Design of Rotary UAV Guidance and Control Systems Utilizing Sliding Mode Control Technique

  • Hong, You-Kyung;Kim, You-Dan
    • International Journal of Aeronautical and Space Sciences
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    • v.13 no.1
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    • pp.90-98
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    • 2012
  • In this paper, the Integrated Guidance and Control (IGC) law is proposed for the Rotary Unmanned Aerial Vehicle (RUAV). The objective of the IGC law is to consider the nonlinear dynamic characteristics of the RUAV and to design a guidance law which takes into consideration the nonlinear relationship between kinematics and dynamics. In order to control the RUAV system, sliding mode control scheme is adopted. As the RUAV is an under-actuated system, a slack variable approach is used to generate the available control inputs. Through the Lyapunov stability theorem, the stability of the proposed IGC law is proved. In order to verify the performance of the IGC law, numerical simulations are performed for waypoint tracking missions.

An Inducement problem on the principle liability without fault in a legislative bill of injury and relief in a medical accident (의료사고피해구제법안상 무과실책임주의 도입 문제)

  • Jeong, Yong-Yeub
    • The Korean Society of Law and Medicine
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    • v.7 no.2
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    • pp.271-310
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    • 2006
  • In the situation of bringing out of social problem about the medical accident and medical dispute, from 1988 the enactment activity for a legislative bill on conciliation of dispute has promoted, a legislative bill on prevention and relief of medical accident was again proposed in December, 2005. This bill has been faced rough going in review process of National Assembly. Because the purpose of this legislative bill is the conciliation of interest of between medical service consumer and medical service supplier, an item of issues of law is no-fault compensation scheme. However, as no-fault compensation scheme runs counter to the principle liability with fault in our civil law, as expected, whether the inducement is valid or, if induced, the problem is not must be totally reviewed. First of all, the general of principle liability without fault and especially the medical system in foreign countries are reviewed, by reviewing an issue and the pros and cons of the inducement of no-fault compensation scheme, this article draws the conclusion. After all, considering that the necessity adapting Gefahrdungschftung in medical accident as much as other industrial fields exists, the many provisions of the principle liability without fault exists in civil law and special law of our law system, and no-fault compensation scheme let legislative purpose be, to what extent, achieved by conciliating patient and doctor, the inducement of principle liability without fault in medical field is reasonable in the aspect of politic and legal system.

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Dynamic Output Feedback Passivation of Nonlinear Systems with Application to Flexible Joint Robots (비선형 시스템의 동적 출력 궤환 수동화의 유연 관절 로봇에의 적용)

  • Son Young-Ik;Lim Seungchul;Kim Kab-Il
    • Journal of Institute of Control, Robotics and Systems
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    • v.10 no.12
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    • pp.1256-1263
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    • 2004
  • Output feedback passivation problem is studied when the given system is not minimum-phase or does not have relative degree one. Using a parallel connection with an additional dynamics, the authors provide a dynamic output feedback control law which renders the composite system passive. Sufficient conditions are presented under which the composite system is output feedback passive. As an application of the dynamic passivation scheme, a point-to-point control law for a flexible joint robot is presented when only the position measurements are available. This provides an alternative way of replacing the role of the velocity measurements for the proportional-derivative (PD) feedback law. The performance of the proposed control law is illustrated in the simulation studies of a manipulator with three revolute elastic joints.

Adaptive control of overmodeled linear time-invariant discrete systems (과모델된 선형 시불변 이산 시간 시스템의 적응 제어법칙)

  • Yang, Hyun-Suk;Lee, Ho-Shin
    • Journal of Institute of Control, Robotics and Systems
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    • v.2 no.2
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    • pp.67-72
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    • 1996
  • This paper presents a parameter adaptive control law that stabilizes and asymptotically regulates any single-input, linear time-invariant, controllable and observable, discrete-time system when only the upper bounds on the order of the system is given. The algorithm presented in this paper comprises basically a nonlinear state feedback law which is represented by functions of the state vector in the controllable subspace of the model, an adaptive identifier of plant parameters which uses inputs and outputs of a certain length, and an adaptive law for feedback gain adjustment. A new psedu-inverse algorithm is used for the adaptive feedback gain adjustment rather than a least-square algorithm. The proposed feedback law results in not only uniform boundedness of the state vector to zero. The superiority of the proposed algorithm over other algorithms is shown through some examples.

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A Proposal of Rural Landscape Policy for Preservation, Formation and Management (농촌경관의 보전.형성.관리를 위한 정책제안 연구)

  • Joo, Shin-Ha
    • Journal of Korean Society of Rural Planning
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    • v.14 no.4
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    • pp.77-86
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    • 2008
  • The purpose of this study is to propose the policies for preservation, formation and management of Korean rural landscape. For this, the current rural landscape policies are examined and recent legislative changes are also surveyed. The Landscape Law and the Comprehensive Countermeasures for Rural Landscape Improvement are the most significant changes. The proposed issues are as follows: 1. the establishment of rural landscape planning system, 2. the arrangement of the criteria and guideline for rural landscape planning and design, 3. the re-arrangement of the rural landscape index and landscape map, 4. the survey and management of the rural landscape amenity, 5. the revitalization of the landscape projects for rural area, 6. the pragmatic connection with other law and system(especially the Landscape Law), 7. the education and cultivation of the rural landscape expert groups.

Technical Specifications for Manufacturer Approval in Railway Safety Law (철도안전법의 제작자 승인 기술기준에 대한 연구)

  • Lee, Hwan-Deok;Jung, Won
    • Journal of Applied Reliability
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    • v.15 no.1
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    • pp.19-26
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    • 2015
  • The amended law of railway safety in Korea has recently come into effect in order to strengthen the railway safety management system. The new law, which took effect March 1, 2014, will implement stricter oversight of railway companies. As a result, a company that manufactures railroad system or components for domestic use must obtain an approval in accordance with the technical specifications of manufacturer approval. Although Korea had established the legal system in enforcing railway safety, the government wants the companies continue to develop the more improved safety systems until they gain competitive edge on the world class railway manufacturers. This paper presents an in-depth analysis of the technical specifications for manufacturer approval in International Railway Industry Standard (IRIS), which is the global standard. This paper also proposes measures and guidelines that would help Korean manufacturers those who want further develop their safety management systems, as a prerequisite for them to obtain the manufacturer approval.

Robust Sliding Mode Control for Path Tracking of Intelligent Mobile Robot

  • Jiangzhou, L-U;Xie Ming
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.109.1-109
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    • 2001
  • This paper deals with the path following problem of car-like intelligent mobile robot. A robust sliding mode control law based on time-varying state feedback is performed via Lyapunov method for path tracking of nonholonomic mobile robot with uncertainties. At first, A sliding control law is designed by combing the natural algebraic structure of the chained form system with ideas from sliding mode theory. Then, a robust control law is proposed to impose robustness against bounded uncertainties in path tracking. The problem of estimating the asymptotic stability region and the sliding domain of uncertain sliding mode system with bounded control input is also discussed. The proposed sliding mode control law can ensure the global reaching condition of the uncertain control system.

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