A new simplified version of the Fuzzy Controller: The Natural Logic Controller
Alejandro Aceves-López, Martin Joseph · 1999
MIMO (multi inputs multi outputs) systems are difficult to be handled by simple Fuzzy Controllers (CF), because of number of rules to specified. The Natural Logic Controller (NLC) overcomes this difficulty by considering the connection of all necessary outputs as a fuzzy-logic combination using t-norms and a last adjustable parameter. This approach propose an important simplification of the FC that allow easy-design for SISO, SIMO and MIMO control problems. This approach takes in to account the constraints of actuator (saturation) and the supportable limits for certain measurable variables, as for example the output signal, to define the universes of discourse. The main features are, smooth input-output mapping, analytically well defined, and is linear around the state space origin. We show in this paper, that it is also possible to test stability and robustness using the Multivariable Circle Criterion.