Serwis Infona wykorzystuje pliki cookies (ciasteczka). Są to wartości tekstowe, zapamiętywane przez przeglądarkę na urządzeniu użytkownika. Nasz serwis ma dostęp do tych wartości oraz wykorzystuje je do zapamiętania danych dotyczących użytkownika, takich jak np. ustawienia (typu widok ekranu, wybór języka interfejsu), zapamiętanie zalogowania. Korzystanie z serwisu Infona oznacza zgodę na zapis informacji i ich wykorzystanie dla celów korzytania z serwisu. Więcej informacji można znaleźć w Polityce prywatności oraz Regulaminie serwisu. Zamknięcie tego okienka potwierdza zapoznanie się z informacją o plikach cookies, akceptację polityki prywatności i regulaminu oraz sposobu wykorzystywania plików cookies w serwisie. Możesz zmienić ustawienia obsługi cookies w swojej przeglądarce.
This paper presents the results of a linear control technique developed for fixed-final-time constrained systems and applied to preferred axis homing missiles. This technique accommodated the nonlinearities, constraints, and the modeling errors of a suboptimal linear design to maintain the target within the missile reachable set. This feature minimized miss distances, and prevented control saturation...
Some issues associated with the design and implementation of an optimal guidance algorithm in Ada for a tactical missile are presented. Limited microprocessor throughput appears to be the most critical implementation issue. This is associated with the run-time overhead of the Ada language and the efficiency of Ada cross-compilers.
This paper discusses some aspects of the design problem involved in the choice of a realization or approximation of a desired system behavior (as for instance dictated by the analytical solutions to a filtering problem) by parameters that can only be approximately adjusted, e.g., due to quantization, component tolerances (analog case) and finite wordlength (discrete case). The paper first addresses...
In recent previous works, dealing with the terminal phase of the missile-aircraft encounter in noisy environment, a new approach of "mixed guidance strategy" was proposed for an assumed planar geometry. If the target aircraft maneuvers and applies electronic jinking simultaneously, the problem becomes a three-dimensional one. The present paper investigates this problem and shows that in...
Midcourse guidance is examined for an air-to-air missile featuring boost-sustain propulsion. A vertical plane, point-mass model is studied with load factor as a control variable. Time-range-energy optimal trajectories are computed, open-loop, via the usual necessary conditions and a multiple-shooting algorithm. A requirement on terminal velocity magnitude is examined for its effect on firing range.
This paper presents experimental results of digital tracking control algorithms applied to a hydraulic linear actuating system for tool positioning in noncircular machining. Noncircular machining is accomplished by controlling the tool position in the direction normal to the surface of the rotating workpiece. Implementation of two robust tracking controllers is presented: one is the adaptive zero...
The stochastic optimal control solution to the Linear-Quadratic-Gaussian problem with partial information is considered where the system parameters operating on the control are assumed to be unknown Gaussian random processes. This class of problems has special properties that are exploited. First, the state and the random parameters are conditionally Gaussian with respect to the measurement history...
Two-stage actuation is presented as a method for improved contouring accuracy of biaxial positioning systems. The method applies the concept of dynamic compensation to a two-stage structure where the position error of the the coarse stage serves as the input to the fine stage. The objective of dynamic compensation is to obtain an overall system with the bandwidth of the fine stage and the range of...
This paper provides an assessment of current air-to-air missile guidance and control technology. Areas explored include target state estimators, advanced guidance laws, and bank-to-turn autopilots. The assumptions, benefits, and limitations of recent applications of nonlinear filtering, adaptive filtering, modern control, adaptive control, dual control, differential game theory, and modern control...
With the current emphasis on precision in science and engineering, there are increasing requirements for precise manipulation systems that operate over a range of several centimeters or greater with an accuracy in the sub-micrometer range. A control concept is presented which addresses the problem of using two controllers operating in a parallel fashion to form the inputs to a pair of cascaded colinear...
The paper presents the design and implementation of a hierarchical structure embedding a complex family of experts for process control. Each member of the expert system solves one of the control problems: from operator assistance to control algorithms synthesis. At the first level the structure of the system integrates four classes of experts. In each class a pyramidal organization of experts establishing...
In this paper the properties gaind from a strengthened H∞ optimization criterion are used in multivariable control system design. The design objectives are specified in terms of the saape (magnitude) of a desired loop transfer function. A controller in a two-feedback-loop scheme is found using H∞ theory to meet the desired loop shape.
In this paper we present a new approach to adaptive robust control. The essential idea involved is to fragment modeling uncertainty in a physical plant into "small" families of plant models for which robust LTI controllers can be readily designed. We then implement a convex combination of these controllers, the parameters of which are tuned based on error measurements. Using this approach...
The `internal model principle' for linear multivariable regulators tells us necessary and sufficient conditions for achieving stabilizing controllers which achieve structurally stable output regulation for classes of deterministic exogenous reference and disturbance signals. In the absence of structural stability considerations, Antoulas has characterized the entire class of stabilizing regulators...
Conditions are given for global stability of an adaptive control law designed for the reduced order model of a class of higher order nonlinear plants. In the presence of unmodeled dynamics. which account for the difference between the model and the plant, the regulation property is preserved in a stability region. The size of the region is estimated via a set of bounds that not only proves robustness,...
The installation of a large constrained multivariable controller on the second stage reactor of Suncor's hydrocracker unit has been completed. The control problem is complex and required an unusual controller structure to allow it to be solved with the computing resources available. The performance of the controller has been good, and has resulted in much more stable and consistent control of the...
The objective is to explore design concepts for self-tuning expert controllers. To accomplish this, two interacting rule based controllers for supervisory control and system optimization are constructed to control a gasoline catalytic reformer. The knowledge bases for the controllers are established from human operator experience and basic engineering knowledge about the process dynamics. Inference...
In this paper a prototype expert system is presented for tuning of PID controllers for single-input single-output systems. The paper first describes general ideas behind the use of expert systems in computer aided control engineering. Next the functional description of the developed expert system is given. Conclusions finish the paper.
An effective and formal design procedure for the design of coupled controllers for coordinated multi-axial motion control applications is described here. The design procedure relies upon representation of the system dynamics using task-based coordinates along and orthogonal to the desired contour in motion space. The multivariable system dynamics, when represented thus, are diagonally dominant or...
Due to geometric nonlinearities and complex dynamics, a decentralized technique for adaptive control for multilink robot arms is attractive. Lyapunov-function theory for stability analysis provides an approach to robust stabilization. Each joint of the arm is treated as a component subsystem. The adaptive controller is made locally stable with servo signals including proportional and integral gains...
Podaj zakres dat dla filtrowania wyświetlonych wyników. Możesz podać datę początkową, końcową lub obie daty. Daty możesz wpisać ręcznie lub wybrać za pomocą kalendarza.