Research articleOutput feedback boundary control of an axially moving system with input saturation constraint

- The input saturation constraint of the actuator is considered in the control design.
- State feedback and output feedback boundary control are both developed.
- The auxiliary system is introduced to eliminate the input saturation effects.
- The high-gain observers are utilized to estimate those unmeasurable states.
- The wellposedness and stability of the closed-loop system are proved.

This paper is concerned with boundary control for an axially moving belt system with high acceleration/deceleration subject to the input saturation constraint. The dynamics of belt system is expressed by a nonhomogeneous hyperbolic partial differential equation coupled with an ordinary differential equation. First, state feedback boundary control is designed for the case that the boundary states of the belt system can be measured. Subsequently, output feedback boundary control is developed when some of the system states can not be accurately obtained. The well-posedness and the uniformly bounded stability of the closed-loop system are achieved through rigorous mathematical analysis. In addition, high-gain observers are utilized to estimate those unmeasurable states, the auxiliary system is introduced to eliminate the constraint effects of the input saturation, and the disturbance observer is adopted to cope with unknown boundary disturbance. Finally, the control performance of the belt system is illustrated by carrying out numerical simulations.