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Develops a fuzzy logic controller for hybrid vehicles with parallel configuration. State of charge of the energy storage and the motor/generator speed; Rules in a fuzzy controller to determine the split between electric motor and internal combustion engine; Implementation of the controller in a forward-looking hybrid vehicle.

A computer-aided design technique to assign tolerances to system components is introduced. The essence of the method is to ac curately represent the allowable margins of the system's perfor mance functions in the percent deviation parameter space (PDPS) and to determine the point in the PDPS corresponding to the most efficient tolerance assignment. The criteria used in volve minimum cost-tolerance assignments.The technique presented solves the tolerance assignment prob lem for a significant class of systems for which one hundred percent yield is sought and whose components are statistically independent. The most salient feature of this technique is the simple and straightforward manner in which the "curse of dimen sionality" associated with tolerance assignment problems is overcome.A computer program has been developed; it accepts a system's topology, nominal component values, a figure-of-merit for system performance, and information relating a component cost to its tolerance. The output of the program includes the set of com ponent tolerances that will produce the least expensive design with a hundred percent yield. As an example, a rather complex low pass filter has been simulated to solve the tolerance assign ment problem. Computation time is about seven seconds on the Univac-1100 computer. [ABSTRACT FROM PUBLISHER]

Many simulation applications require the generation of a set of sample functions to characterize the physical system being modeled. Probability modeling using minimal data bases are reviewed and model credibility issues examined. Modeling methods include the Box-Jenkins time series, the fixed- memory and the α-β filters, the generalized expand ing memory filter, the Kalman filter, the Bayes filter, and the square-root filter. Such methods are particularly suitable in situations involving limited data, for instance, where the physical sys tem observations may be limited by cost or by the physical experiment. Theil's Inequality Coefficient (TIC) is presented as a basis for model validation in specific applications. An example illustrates the special utility of TIC for simulation model validation. [ABSTRACT FROM PUBLISHER]

Simulation of missile systems is mainly used to pre dict missile flight and terminal miss distance and to study flight safety. Computer simulations of mis sile systems produce results that otherwise could only be obtained by actual tests and missile flights. The increasing cost of firings limits their number and hence reduces the amount of available flight-test data. Theil's inequality coefficients (TIC) and their geometric representations are the basis for a procedure which provides insight into the validity of a simulation and reduces the dependence of validation on flight-test data. [ABSTRACT FROM PUBLISHER]