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Journal Article

Digital transfer functions for microcomputer control.

About: This article is published in IEEE Transactions on Systems, Man, and Cybernetics.The article was published on 1979-01-01 and is currently open access. It has received 22 citations till now. The article focuses on the topics: Thesaurus (information retrieval).
Citations
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Journal ArticleDOI
01 Oct 1987
TL;DR: Simulation studies of two- and three-degree-of-freedom systems show the application of an adaptive control algorithm to overcome unknown and nonlinear relations in the feature to world space mapping.
Abstract: Sensor-based robot control may be viewed as a hierarchical structure with multiple observers. Actuator, feature-based, and recognition observers provide the basis for multilevel feedback control at the actuator, sensor, and world coordinate frame levels, respectively. The analysis and design of feature-based control strategies to achieve consistent dynamic performance is addressed. For vision sensors, such an image-based visual servo control is shown to provide stable and consistent dynamic control within local regimes of the recognition observer. Simulation studies of two- and three-degree-of-freedom systems show the application of an adaptive control algorithm to overcome unknown and nonlinear relations in the feature to world space mapping.

889 citations

Journal ArticleDOI
TL;DR: This paper reviews the issues of digital control implementation, from algorithms through current hardware up to the various problems arising with non-ideal behaviour of digital controllers.

158 citations

Proceedings ArticleDOI
25 Mar 1985
TL;DR: In this article, the authors formalize an analytical approach to dynamic robot visual servo control systems by first casting position-based and image-based strategies into classical feedback control structures, and then using image features (e.g., image areas, and centroids) as feedback control signals, thus eliminating a complex interpretation step.
Abstract: Sensory systems, such as computer vision, can be used to measure relative robot end-effector positions to derive feedback signals for control of end-effector positioning. The role of vision as the feedback transducer affects closed-loop dynamics, and a visual feedback control strategy is required. Vision-based robot control research has focused on vision processing issues, while control system design has been limited to ad-hoc strategies. We formalize an analytical approach to dynamic robot visual servo control systems by first casting position-based and image-based strategies into classical feedback control structures. The image-based structure represents a new approach to visual servo control, which uses image features (e.g., image areas, and centroids) as feedback control signals, thus eliminating a complex interpretation step (i.e., interpretation of image features to derive world-space coordinates). Image-based control presents formidable engineering problems for controller design, including coupled and nonlinear dynamics, kinematics, and feedback gains, unknown parameters, and measurement noise and delays. A model reference adaptive controller (MRAC) is designed to satisfy these requirements.

130 citations

Journal ArticleDOI
TL;DR: The adaptive Generalized Predictive Controller (Clarke et al., 1987a, b) is capable of controlling plants with variable dead-time, unknown model orders and unstable poles and zeros as discussed by the authors.
Abstract: The adaptive Generalized Predictive Controller (Clarke et al., 1987a, b) is capable of controlling plants with variable dead-time, unknown model orders and unstable poles and zeros. This paper shows how the GPC control law can be written in an equivalent general linear transfer function form which simplifies closed-loop (eg. root locus) analysis. Three recommended strategies for selecting the design parameters during the commissioning stage allow the user to adjust the closed-loop speed of response on-line using only a single active tuning parameter. Experimental runs confirm the ability of adaptive GPC to provide a consistent closed-loop response in spite of large process changes. Le regulateur predictif generalise adaptatif (Clarke et al., 1987a, b) est capable de controder des procedes ayant un temps mort variable, des ordres de modeles inconnus et des poes et zeros instables. On montre dans cet article comment la loi de controle du regulateur peut etre ecrite sous forme de fonction de transfert lineaire generale equivalente qui simplifie l'analyse a boucle fermee (p. ex. le locus de base). Trois strategies recommandees pour la selection des parametres de conception durant le stade de mise en fonctionnement perrnettent a l'utilisateur d'adapter la vitcsse de repons en boucle fermee en ligne en utilisant un seul parametre de regulation actif. Les essais experimentaux confirment la capacite du regulateur de fournir une reponse en boucle fermee coherente en depit d'importants changements de procedes.

76 citations

Journal ArticleDOI
01 Jan 1993
TL;DR: In the fast sampling limit, the delta operator model tends to the dynamic system model, which unifies continuous and discrete time control engineering and paves the way for the design of robust computational algorithms.
Abstract: For control system analysis and design, and high-speed real-time computation, the computational formulation, properties and applications of the delta operator model of dynamic physical systems are highlighted. Doubling algorithms for reliable computation are formulated, and the transfer function matrix of the delta operator model is illustrated. In the fast sampling limit, the delta operator model tends to the dynamic system model. This intrinsic property of the delta operator model unifies continuous and discrete time control engineering and paves the way for the design of robust computational algorithms. >

53 citations

References
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Book
01 Jan 1977
TL;DR: In this chapter,sequency as a generalized frequency is introduced, and the frequency is used as a parameter to distinguish individual functions that belong to sets of nonsinusoidal functions.
Abstract: sequency as a generalized frequency is introduced, and the frequency is used as a parameter to distinguish individual functions that belong to sets of nonsinusoidal functions. The sixth chapter is devoted to the study of the Walsh-Hadamard transform (WHT) and algorithms to compute it. The concept of the Walsh spectra and their properties are presented with physical significance. Special attention is given to the analogy between the Walsh-Hadamard and the discrete Fourier transforms. In Chapter 7, a study is made of the generalized Haar, Slant, and discrete cosine transforms. Fast algorithms to compute these transforms

2,372 citations

Book
01 Jan 1977
TL;DR: This chapter introduces the z-Transform, a new type of transform that combines Laplace Transforms, z-Transforms and Modified Z-TRANSFORMS with Convolution Integral to achieve state-of-the-art control of Discrete-Data Systems.
Abstract: Each chapter ends with Problems and References Chapter One includes only References) Introduction 1. Signal Conversion and Processing 2. The z-Transform 3. Transfer Functions, Block Diagrams and Signal Flow Graphs 4. The State Cariable Technique 5. Controllability, Observability and Stability 6. Frequency-Domain Analysis 7. Digital Simulation and Digital Redesign 8. Design of Discrete-Data Systems 9. Optimal Control 10. Micro-processor and DSP Controls Appendices: A. Fixed-Point and Floating-Point Numbers B. Mathematical Modeling of Sampling by Convolution Integral C. Table of Laplace Transforms, z-Transforms and Modified Z-TRANSFORMS D. General Gain Formula for Signal Flow Graphs E. Routh's Tabulation for Stability Analysis F. Galil DMC-100 Motion Controller Board

1,070 citations

Book
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347 citations

Book
01 Jan 1975
TL;DR: This paper presents a meta-modelling procedure called “Smart Card” which automates the very laborious and therefore time-heavy and expensive and expensive process of manually cataloging and cataloging the components of a computer.
Abstract: Review of least squares, orthogonality and the Fourier series review of continuous transforms transfer functions and convolution sampling and measurement of signals the discrete Fourier transform the fast Fourier transform the z-transform non-recursive digital systems digital and continuous systems simulation of continuous systems analogue and digital filter design review of random functions correlation and power spectra least-squares system design random sequences and spectral estimation.

286 citations