Designing Type-2 Fuzzy Logic System Controllers via Fuzzy Lyapunov Synthesis for the output regulator of a servomechanism with nonlinear backlash

Fuzzy Lyapunov synthesis is extended to the design of type-2 fuzzy logic system controllers for the output regulation problem for a servomechanism with nonlinear backlash. The problem in question is to design a feedback controller so as to obtain the closed-loop system in which all trajectories are bounded and the load of the driver is regulated to a desired position while also attenuating the influence of external disturbances. The servomotor position is the only measurement available for feedback; the proposed extension is far from trivial because of nonminimum phase properties of the system. Performance issues of the type-2 fuzzy logic regulator constructed are illustrated in a simulation study.