Patent ID: 8595162
Filing Date: 2013-11-26
Classification: G05B

Abstract:
1. A robust controller for nonlinear MIMO systems, comprising: a radial basis function (RBF) neural network accepting reference trajectory inputs for a nonlinear process, the RBF neural network having an unconstrained output responsive to the nonlinear process control inputs; means for transforming the RBF output into constrained control outputs acceptable by the nonlinear process, the nonlinear process having inputs accepting the constrained control outputs from the transforming means; a summer accepting high fidelity and noisy outputs of the nonlinear process, the summer providing a computed sum of the high fidelity and noisy outputs of the nonlinear process; a difference calculator performing a difference calculation between the reference trajectory control inputs and the computed sum provided by the summer, a result of the difference calculation being provided by an output of the difference calculator, the difference calculator output representing an error of the nonlinear process output, the nonlinear process output error being characterized by an equation: an adaptation algorithm processor accepting the output of the difference calculator; a linear estimator outputting a linear estimation signal to the adaptation algorithm processor; and a weight updater accepting an output of the adaptation algorithm processor, the weight updater having a weight updater output connected to the RBF network for adjusting weights of the RBF network, the weight updater output being characterized by an equation, where e l (k) corresponds to error at the l th output, ψ lj is the element at the l th row and j th column of the matrix Ψ, η is the learning rate of the RBF neural network, w j is the vector for the weights of j th RBF output, m is the number of outputs of the process, and φ(k) is the basis function vector, α is an upper and lower limit of a control signal constraint, and β is a slope adjustment parameter of a linear part of the transforming means.