Nonlinear adaptive observer for Unmanned Aerial Vehicle without GPS measurements

The present work deals with the classical problem of speed estimation for a small 4 rotors helicopter drone based on acceleration, rotation angles and angular speed measurements only. This problem concerns indoors applications as well as outdoors applications close-by large structures. Small Unmanned Air Vehicles (UAV) are commonly used for inspection applications such as beneath bridges, water dams, industrial facilities and interior of large structures and pipes. An observer is designed based on nonlinear adaptive techniques providing a global exponential solution to this problem when exact measurements are available. Simulation results illustrate the observer performance and suggest that the estimator presents good robustness in the more realistic case of noisy acceleration measurements.