Title :
Learning control using fuzzified self-organizing radial basis function network
Author :
Nie, Junhong ; Linkens, D.A.
Author_Institution :
Dept. of Electr. Eng., Nat. Univ. of Singapore, Singapore
fDate :
11/1/1993 12:00:00 AM
Abstract :
This note describes an approach to integrating fuzzy reasoning systems with radial basis function (RBF) networks and shows how the integrated network can be employed as a multivariable self-organizing and self-learning fuzzy controller. In particular, by drawing some equivalence between a simplified fuzzy control algorithm (SFCA) and a RBF network, we conclude that the RBF network can be interpreted in the context of fuzzy systems and can be naturally fuzzified into a class of more general networks, referred to as FBFN, with a variety of basis functions (not necessarily globally radial) synthesized from each dimension by fuzzy logical operators. On the other hand, as a result of natural generalization from RBF to SFCA, we claim that the fuzzy system like RBF is capable of universal approximation. Next, the FBFN is used as a multivariable rule-based controller but with an assumption that no rule-base exists, leading to a challenging problem of how to construct such a rule-base directly from the control environment. We propose a simple and systematic approach to performing this task by using a fuzzified competitive self-organizing scheme and incorporating an iterative learning control algorithm into the system. We have applied the approach to a problem of multivariable blood pressure control with a FBFN-based controller having six inputs and two outputs, representing a complicated control structure
Keywords :
biocontrol; blood; feedforward neural nets; fuzzy control; fuzzy logic; inference mechanisms; learning (artificial intelligence); multivariable control systems; pressure control; self-adjusting systems; fuzzified self-organizing radial basis function network; fuzzy reasoning systems; iterative learning control algorithm; learning control; multivariable blood pressure control; multivariable self-learning fuzzy controller; self-learning fuzzy controller; Control system synthesis; Control systems; Fuzzy control; Fuzzy logic; Fuzzy reasoning; Fuzzy systems; Iterative methods; Network synthesis; Pressure control; Radial basis function networks;
Journal_Title :
Fuzzy Systems, IEEE Transactions on