A new, robust algorithm called the minimum time change detection algorithm (MTCDA) is developed for flight control systems which minimzes the time delay in detecting a change in a linear system for a fixed false-alarm...
详细信息
A new, robust algorithm called the minimum time change detection algorithm (MTCDA) is developed for flight control systems which minimzes the time delay in detecting a change in a linear system for a fixed false-alarm probability. The MTCDA is illustrated for the case of a linear system with a single change in the control gain matrices at random time whose a priori distribution is known, is considered. In the case of unknown change detection it can be concluded that a 10 percent change detector, which is the smallest one, is sufficient and robust in the sense that it could detect any change with subminimal detection delay. The detection delay of MTCDA is much smaller than that of the whiteness test. (AIAA)
An algorithm for real-time guidance of missiles has been developed using a control formulation based on Lagrange's form of the equinoctial variables which assures that the Jacobian of the nonlinear algebraic equat...
详细信息
An algorithm for real-time guidance of missiles has been developed using a control formulation based on Lagrange's form of the equinoctial variables which assures that the Jacobian of the nonlinear algebraic equations do not become singular during the iterative solution of the equations. The formulations are described here along with how the aerodynamic data are handled in implementing the formulation. (AIAA)
A method to design a model reference adaptive controller (MRAC) has been proposed for an aeroengine speed digital control system. The adaptive control device is designed using fuzzy control theory, A digital simulatio...
详细信息
A method to design a model reference adaptive controller (MRAC) has been proposed for an aeroengine speed digital control system. The adaptive control device is designed using fuzzy control theory, A digital simulation of the entire control system has been executed and indicated that precision control of aeroengine speed is improved, Control algorithm complexity is reduced using this method, This new method is proposed as a tool to design MRACs for those systems that are high-order, nonlinear, or imprecisely modeled.
The results of a computational evaluation of several Newton's and quasi-Newton's method solvers are discussed and analyzed. Computer time and memory requirements for iterating a solution to the steady state ar...
详细信息
The results of a computational evaluation of several Newton's and quasi-Newton's method solvers are discussed and analyzed. Computer time and memory requirements for iterating a solution to the steady state are recorded for each method. Roe's flux-difference splitting together with the Spekreijse/Van Albada continuous limiter is used for the spatial discretization. Sparse matrix inversions are performed using a modified version of the Boeing real sparse library routines and the conjugate gradient squared algorithm. The methods are applied to exact and approximate Newton's method Jacobian systems for flat plate and flat-plate/wedge-type geometries. Results indicate that the quasi-Newton's method solvers do not exhibit quadratic convergence, but can be more efficient than the exact Newton's method in select cases.
The minimum-variance reduced-order (MVRO) filter is an algorithm that has become popular in the guidance and navigation community as a tool for designing and evaluating the performance of candidate reduced-order filte...
详细信息
The minimum-variance reduced-order (MVRO) filter is an algorithm that has become popular in the guidance and navigation community as a tool for designing and evaluating the performance of candidate reduced-order filters. Its utility rests on the assumption that the MVRO algorithm yields the optimum (in a minimum-variance sense) performance possible with a given reduced-order filter. The analysis and examples in this paper show that this is not the case and that the MVRO algorithm merely yields an optimal estimate immediately after the first measurement update. It is shown how a new MVRO gain matrix may be derived that will yield optimum results at some specified time in the future. The main point of the analysis is to prove that, in general, it is not possible to specify a discrete reduced-order filter that is always minimum-variance. The minimum- variance condition can only be achieved at a specific time - before and after that time, other filter gain hisories could provide better performance. (Author)
暂无评论