Adaptive sliding mode control using simple adaptive control for SISO nonlinear systems

Sliding mode control (SMC) has a strong capability of controlling nonlinear systems with uncertainties. However, it requires thorough knowledge of parameters and dynamics of the controlled plant, which are difficult to be obtained or may be unknown. This will cause difficulties in calculating equivalent control law of SMC. To overcome this problem, this paper proposes an adaptive SMC using simple adaptive control (SAC) developed for single-input single-output (SISO) nonlinear systems with unknown parameters and dynamics. The role of SAC is to construct an equivalent control input of adaptive SMC. To construct a corrective control input, this paper applies the method using the sign function with a modified sliding surface. Finally, the effectiveness of the proposed method is confirmed through computer simulation.