Nonlinear optimal control for electropneumatic actuators

In the article's control approach, the dynamic model of the electropneumatic actuator undergoes approximate lin-earization with the use of first-order Taylor series expansion and through the computation of the associated Jacobian matrices. The linearization takes place at each sampling instance, around a temporary operating point which is defined by the present value of the actuator's state vector and by the last sampled value of the control inputs vector. For the approximately linearized model of the actuator an H-infinity stabilizing controller is designed. The feedback gains of the controller are computed through the solution of an algebraic Riccati equation, taking place at each time-step of the control method. The global stability properties of the control method are proven through Lyapunov analysis.