Model-Free Adaptive Control of MIMO Nonlinear Systems With Prescribed Tracking Performance

This paper investigates the problem of model-free tracking control of a class of multi-input multi-output nonlinear systems with inputs coupling and external disturbances. A novel directly adaptive prescribed performance controller with the constraint transformation and the Nussbaum gain technique is developed. It guarantees that the system outputs track the reference signals with the prescribed rate, overshoot and accuracy. The controller depends on information of neither the multiplicative and additive system nonlinearities nor the external disturbances. Even so, no neural networks, fuzzy logic systems or disturbance observers are employed, yielding a simple control algorithm. The simulation results verify the effectiveness of the proposed control scheme.