Interval type 2 fuzzy sliding mode control with application to inverted pendulum on a cart

Conventional sliding mode control (SMC) usually causes chattering problem. Fuzzy sliding mode has been proposed in literature to reduce chattering. Interval type 2 fuzzy logic systems (IT2FLS) enhances fuzzy system performance by incorporating uncertainties in rule base. In this paper, the reaching component of SMC is replaced by an IT2FLS to reduce chattering taking into consideration possible system uncertainties. The inputs of the IT2FLS are the sliding variable and its derivative. To investigate the validity of the proposed controller, it is used to control a simulated model of an under-actuated, unstable inverted pendulum. The Simulation results show that the proposed controller can handle more efficiently parameter uncertainty and disturbance in stabilization of the pendulum and cart position tracking to a reference trajectory.