A new approach for designing robust adaptive fuzzy sliding mode controller

In this paper a new method for Adaptive Fuzzy Sliding Mode Controller (AFSMC) is proposed for a Quadrotor helicopter and then this controller is developed by Parallel Fuzzy System (AFSMCP). Because oscillations in input signal and external disturbances, weights vector of fuzzy system may have unwanted changes and even it can be drifted to very large amounts. This event can eventuate chattering phenomenon in controlled signal and if there are un-modeled dynamics, it will even result instability in output of system. To eliminate of undesirable increases of weight vector while the adaptation law is being proceed, a parallel fuzzy system is used in addition of main fuzzy system. This fuzzy system controlled the speed and variation rate of main fuzzy system. In this technique, weights vector of main fuzzy system will be forced to follow the consequent weights vector of the parallel fuzzy system. The simulation results show effectiveness and robustness of proposed method.