Finite-time observer-based output-feedback control for the global stabilisation of the PVTOL aircraft with bounded inputs

In this work, an output-feedback scheme for the global stabilization of the PVTOL aircraft with bounded inputs is developed taking into account the positive nature of the thrust. The global stabilization objective is proven to be achieved avoiding input saturation and by exclusively considering the system positions in the feedback. To cope with the lack of velocity measurements, the proposed algorithm involves a finite-time observer. The generalized versions of the involved finite-time stabilizers have not only permitted to solve the output-feedback stabilization problem avoiding input saturation, but also provide additional flexibility in the control design that may be used in aid of performance improvements. With respect to previous approaches, the developed finite-time-observer-based scheme guarantees the global stabilization objective disregarding velocity measurements in a bounded input context. Simulation tests corroborate the analytical developments. The study includes further experimental results on an actual flying device. Index Terms non-linear control; global stabilization; output feedback; finite-time observers; bounded inputs; PVTOL aircraft