Event-Triggered Fuzzy Flight Control of a Two-Degree-of-Freedom Helicopter System

In this article, the problem of flight control for a two-degree-of-freedom helicopter system is studied. Since the helicopter is a multiinput, multioutput nonlinear control system, a Takagi-Sugeno (T-S) fuzzy model is applied to approximate the system. All submodels of the new T-S fuzzy model contain constant terms due to the nonlinear characteristics of the helicopter system. In this article, sampled-data control is considered and the sampled data are transmitted to the system over a communication network. A large amount of sampled data transmitted over the network can significantly increase the computational and communication burdens for the network with a limited bandwidth. To overcome this difficulty, an event-triggered mechanism is introduced. In order to validly control the T-S fuzzy system, a fuzzy proportional integral-derivative (PID) controller is designed based on the Lyapunov method and practical stability criteria, which are obtained by using improved integral inequalities and the linear matrix inequality technique. Finally, a numerical example is given to show the effectiveness of the obtained results.