摘要:

AbstractTwo control schemes are devised to minimize a quadratic cost functional associated with a time varying linear system, when the linear system forms part of a plant that may contain delays in both control and measurement. Control scheme (1) makes use of prior knowledge of the initial state of the linear system, whereas control scheme (2) does not. Both control schemes contain models of the plant and any difference between plant and model is referred to as mismatch. Matched control scheme (1) is optimal, whereas matched control scheme (2) is optimal if and only if the plant does not contain measurement delay. As matched control scheme (2) is suboptimal for plant with delay in measurement, in this instance mismatch may improve performance. The type of mismatch which may produce this improvement is obtained using a concept referred to as equivalence.

ISSN:0143-2087    

DOI:10.1002/oca.4660030301

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractThis paper addresses the problem of parameter sensitivity reduction in linear regulators. It is shown that the minimization of a modified performance index which includes a quadratic term of trajectory sensitivity (state, output, or control) subject to the augmented sensitivity system dynamics causes reduction not only in trajectory sensitivity but also in cost sensitivity. Inclusion of both state sensitivity and control sensitivity terms in the cost functional reduces cost sensitivity and facilitates the unification of two approaches previously treated independently: ‘trajectory sensitivity reduction’ and ‘cost sensitivity reduction’. Two control design methods, one based on a linear formulation and the other on a non‐linear formulation, are given for both deterministic and stochastic systems. The improvement of these methods over existing methods is illustrated by

ISSN:0143-2087    

DOI:10.1002/oca.4660030302

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractModels of optimal control of two‐species ecological systems are considered on an infinite time horizon. Conditions are obtained under which the optimal exploitation of the system is stabilizing. Thus, a stationary state toward which all optimal trajectories must converge is defined. This extends to this class of models, the co‐called turnpike property of optimal economic growth mod

ISSN:0143-2087    

DOI:10.1002/oca.4660030303

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractThe integrals of motion for an inverse‐square force field and a necessary condition for optimality are used in a transfer orbit co‐ordinate system to formulate the solution of the optimal two‐impulse transfer between fixed position and velocity vectors on Keplerian orbits. In this co‐ordinate system, the equations reveal two asymptotes that are useful in analysing the solution. It is shown that there are only two real extremals (both minimums) which are separated by an asymptote. An approximate analytic solution is also obtained by ignoring a quadratic term whose coefficient is approximately zero for a large class of orbit transfer p

ISSN:0143-2087    

DOI:10.1002/oca.4660030304

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractRecent results in design differentiation of structural displacement are used to develop an iterative optimization method that explicitly treats bounds on the maximum displacement of structural elements. Computable design derivative expressions are employed, and a finite‐element computational algorithm is presented for obtaining design derivatives needed in structural optimization. A function‐space, gradient‐projection, optimization technique which uses these derivatives is presented. The method is applied to beam and plate optimization problems to illustrate its use and to evaluate its computational efficiency. Results obtained using this method are compared with solutions reported in the literature. The method is shown to be both generally applicable and numerically effi

ISSN:0143-2087    

DOI:10.1002/oca.4660030305

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

ISSN:0143-2087    

DOI:10.1002/oca.4660030306

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

摘要:

AbstractA simple guidance scheme is proposed which approximately optimizes the range of the glide phase of a boost‐glide vehicle's trajectory. The scheme requires only altitude, flight‐path angle, and attitude measurements for implementation. The guidance law provides an attitude command based on the actual flight‐path angle and on a calculated flight‐path angle associated with that of an equilibrium, constant‐dynamic‐pressure, glide of maximum lift‐to‐drag ratio. By proper weighting of these two inputs, an approximately optimal guidance control is realized. Two examples are given which demonstrate the trajectory characteristics for a high‐performance aircraft and for a mis

ISSN:0143-2087    

DOI:10.1002/oca.4660030307

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

ISSN:0143-2087    

DOI:10.1002/oca.4660030308

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

ISSN:0143-2087    

DOI:10.1002/oca.4660030309

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY

ISSN:0143-2087    

DOI:10.1002/oca.4660030310

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1982

数据来源: WILEY