Victor Gibert

Nonlinear observers in vision system: Application to civil aircraft landing

In this paper, a new pose estimation solution for perspective vision system is presented and applied to a civil aircraft landing phase. Vision sensor is used to overcome the need for external technologies and runway knowledge. Two nonlinear observers are proposed for on-line estimation of the deviations of the aircraft w.r.t. the runway. These nonlinear observers are based, first, on a high-gain approach, and then on a high-order sliding-mode approach, allowing robustness and finite time convergence. The originality of the presented results consists in estimating deviations with redundant informations in order both to increase efficiency of the observer and guarantee observability. Simulation results obtained on a realistic landing scenario are presented.

A New Observer for Range Identification in Perspective Vision Systems

Automatic guidance of flying vehicle usually needs external information. GPS (Global Positionning System) is a worldwide technology which provides to the guided system its deviations with respect to its guidance objective. Nevertheless, this technology is not available everywhere (indoor evironment), everytime (in case of failure) and not precise enough to ensure critical operations as landing a civil aircraft. Current civil aircraft are able to land autonomously on a runway thanks to ILS (Instrument Landing System) or differential GPS. However, these equipment are expensive and can fail. In frame of the future aircraft, manufacturers like AIRBUS company study the possibility to make aircraft landing everywhere (unequipped or unknown runway) without using informations from external systems.