Adaptive fuzzy control for multi-input multi-output nonlinear systems with unknown dead-zone inputs

• The adaptive fuzzy control is proposed for MIMO nonlinear systems with unknown dead-zone inputs.
• The symmetric matrix decomposition technique is used to design the controller.
• The controller is developed to avoid the possible controller singularity problem.
• The controller is developed to avoid the parameter initialization condition constraints problem.
• The well-defined dynamic robust controller is employed to compensate for the lumped errors.

This paper presents an adaptive fuzzy control scheme for a class of uncertain multi-input multi-output (MIMO) nonlinear systems with the nonsymmetric control gain matrix and the unknown dead-zone inputs. In this scheme, fuzzy systems are used to approximate the unknown nonlinear functions and the estimated symmetric gain matrix is decomposed into a product of one diagonal matrix and two orthogonal matrices. Based on the decomposition results, a controller is developed, therefore, the possible controller singularity problem and the parameter initialization condition constraints problem are avoided. In addition, a dynamic robust controller is employed to compensate for the lumped errors. It is proved that all the signals in the proposed closed-loop system are bounded and that the tracking errors converge asymptotically to zero. A simulation example is used to demonstrate the effectiveness of the proposed scheme.

Overall scheme of the adaptive fuzzy control. Figure optionsDownload as PowerPoint slide