Nonlinear dynamic system with variable coefficients has been considered. For this system, after linearization, a fuzzy controller has been synthesized. Comparison with a traditional controller has been conducted. Corresponding qualitative and quantitative estimates have been provided.
A two-mass system is investigated. It is considered as a set of dynamical subsystems. To switch between these subsystems, fuzzy controller is synthesised. The research is held for the case when one subsystem is unstable having one root in the right-hand side of the plane. The stability of the overall system, depending on the stability of the subsystems of which it is composed is examined. For this, a 3D hodograph is used. Quality indexes of the system with unstable subsystem are calculated. The case when the system operates under external perturbations is consider.