摘要:

AbstractSome new results continuing the development of a theory for bounding the optimal value of a quadratic cost function subject to a linear system constraint are presented.The observed property of the nesting of increasing orders of bounds is formalized and proven. This property is shown to be related to the successive inclusion of the constraint sets. A unified result for the nesting and convergence of the bound sequences is also given to conclude this analysis.Extension of the bound derivation to that of a limiting situation based on the introduction of an asymptotic parameter into the control weight is developed in detail. The upper bounds are shown to collapse into a single value, and the lower bounds form a set of nested limit values.

ISSN:0143-2087    

DOI:10.1002/oca.4660010402

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

年代:1980

数据来源: WILEY

摘要:

AbstractThe mission performance characteristics of ramjet‐propelled missiles are highly dependent upon the trajectory flown. Integration of the trajectory profile with the ramjet propulsion system performance characteristics to achieve optimal missile performance is very complex. Past trajectory optimization methods have been extremely problem dependent and require a high degree of familiarity to achieve success. A general computer code (CTOP) has been applied to ramjet‐powered missiles to compute open‐loop optimal trajectories. CTOP employs Chebyshev polynomial representations of the states and controls. This allows a transformation of the continuous optimal control problem to one of parameter optimization. With this method, the trajectory boundary conditions are always satisfied. State dynamics and path constraints are enforced via penalty functions. The presented results include solutions to minimum fuel‐to‐climb, minimumtime‐to‐climb, and minimum time‐to‐target i

ISSN:0143-2087    

DOI:10.1002/oca.4660010403

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

年代:1980

数据来源: WILEY

摘要:

AbstractTransient response and tracking characteristics of three adaptive identifiers are illustrated and compared experimentally through digital simulation. Focus is placed on series‐parallel (SP) identifiers, with and without auxiliary error signals. The identifiers are algorithms which have adjustable coefficients and are designed to follow the process output. At each computational cycle, the coefficients of the identifier (and the error signals) are updated in response to the tracking error between the process and identifier outputs. The process is simulated on an EAI TR‐20 analogue computer, and the identification algorithms are implemented on a PDP‐11/40 minicomputer. Testing is distributed over three processes commonly encountered by the control engineer. Variable adaptation gains, which are positive functions of the absolute value of the tracking error, accelerate the convergence of the identifiers. The experimental results are summarized in terms of the computational requirements of the identi

ISSN:0143-2087    

DOI:10.1002/oca.4660010404

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

年代:1980

数据来源: WILEY

摘要:

AbstractA class of systems having white noise parameter variations is considered. Solutions of the infinite‐time quadratic optimal control (LQOC) and differential game (LQDC) problems are considered. It is shown that guaranteed cost solutions of these problems are possible if the effects of parameter uncertainties are first taken into account in a specified manner. The method is illustrated through a numerical exampl

ISSN:0143-2087    

DOI:10.1002/oca.4660010405

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

年代:1980

数据来源: WILEY

摘要:

AbstractIn this paper, we describe an exact solution method for the problem of optimally controlling a deterministic discrete linear system with piecewise quadratic cost functional containing a ‘dead‐zone’. This model generalizes the well‐known optimal control model for a linear system with (symmetric) quadratic objective functional. This more general problem is solved by using concepts and techniques from the theory of nonlinear programming, for example Kuhn‐Tucker theory, duality, linear complementarity, and Lemke's algorithm. We apply the results to the solution of a 25‐period deterministic pension funding problem which is modelled as a discrete‐time optimal control problem. The controls for this problem are company contributions and investment amounts, and the state is the value of the

ISSN:0143-2087    

DOI:10.1002/oca.4660010406

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

年代:1980

数据来源: WILEY

摘要:

AbstractThis paper treats an optimal design problem of an elastic upright structure which can be regarded as a column. The optimal shape of the structure, which makes the lowest natural frequency as large as possible, is determined under several equality and inequality constraints. A necessary condition for optimality is derived, and a numerical procedure for obtaining the optimal shape is discussed. The piecewise Hermite interpolation technique and the Rayleigh‐Ritz method are employed for computing the smallest eigenvalue and the corresponding eigenfunction. Several numerical results are presente

ISSN:0143-2087    

DOI:10.1002/oca.4660010407

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

年代:1980

数据来源: WILEY

摘要:

AbstractPrimer vector theory is used in analysing a set of linear relative‐motion equations—the Clohessy‐Wiltshire (C/W) equations—to determine the criteria and necessary conditions for an optimalN‐impulse trajectory. Since the state vector for these equations is defined in terms of a linear system of ordinary differential equations, all fundamental relations defining the solution of the state and costate equations and the necessary conditions for optimality can be expressed in terms of elementary functions. The analysis develops the analytical criteria for improving a solution by (1) moving any dependent or independent variable in the initial and/or final orbit, and (2) adding intermediate impulses. If these criteria are violated, the theory establishes a sufficient number of analytical equations. The subsequent satisfaction of these equations will result in the optimal position vectors and times of anN‐impulse trajectory.The solution is examined for the specific boundary conditions of (1) fixed‐end conditions, two‐impulse, and time‐open transfer; (2) an orbit‐to‐orbit transfer; and (3) a generalized rendezvous problem. A sequence of rendezvous problems is solved to illustrate the analysis and the co

ISSN:0143-2087    

DOI:10.1002/oca.4660010408

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

年代:1980

数据来源: WILEY

ISSN:0143-2087    

DOI:10.1002/oca.4660010409

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

年代:1980

数据来源: WILEY

ISSN:0143-2087    

DOI:10.1002/oca.4660010410

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

年代:1980

数据来源: WILEY

ISSN:0143-2087    

DOI:10.1002/oca.4660010411

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

年代:1980

数据来源: WILEY