Discontinuous High-Gain Observer in a Robust Control UAV Quadrotor: Real-Time Application for Watershed Monitoring

Abstract

A control algorithm that is robust with respect to wind disturbances for a quadrotor UAV attitude dynamics is presented. The proposed approach consists of a high-gain observer based on a discontinuous technique. Such an algorithm is embedded on board the quadrotor. The high-gain observer estimates external disturbances such as wind and parameter uncertainties, and a control algorithm is designed to compensate these undesired effects. The observer design is based on Lyapunov stability theory; simulation results and experiments validate the nonlinear observer performance and robustness of the approach under windy conditions. Also, a photogrammetry survey was carried out to develop Digital Elevation Models in order to experimentally demonstrate the effectiveness of our approach. The accuracy of such models was compared and the performance improvement is demonstrated.

Robust Formation Control Based on Leader-Following Consensus in Multi-Agent Systems With Faults in the Information Exchange: Application in a Fleet of Unmanned Aerial Vehicles

“…In this work, wind turbulence affecting the fleet of UVAs is considered as reported in [63] and [64]. Air mass motion is represented in (29) where ϒ (x i ,y i ,z i ),s and (x i ,y i ,z i ),s are randomly selected frequencies and phase shifts in each component of each UAV, S is the number of sinusoids, w (x i ,y i ,z i ),0 is the static wind vector, and the coefficients a (x i ,y i ,z i ),s defines the power spectral density selected as reported in [63].…”

A turbidity sensor development based on NL-PI observers: Experimental application to the control of a Sinaloa’s River Spirulina maxima cultivation

“…where the disturbance is a bounded function, as well as being Lipschitz in the same sense as described in refs. [41][42][43]. This function ( ) δ t can represent unmodeled system phenomena, an external signal, or even a poor control action.…”

Robust Backstepping Trajectory Tracking Control of a Quadrotor with Input Saturation via Extended State Observer

“…Although the authors of [21][22][23] investigated backstepping controllers based on a DO and demonstrated good tracking performance, the authors of [24][25][26] devised DO-based tracking sliding mode controllers. High gain observers and robust controllers to deal with the tracking problem have also been presented in [27,28]. However, all the control strategies in [21][22][23][24][25][26][27][28], especially with regard to the backstepping controllers, require full-state measurements that may not be possible due to insufficient sensor numbers and/or sensor faults.…”

“…High gain observers and robust controllers to deal with the tracking problem have also been presented in [27,28]. However, all the control strategies in [21][22][23][24][25][26][27][28], especially with regard to the backstepping controllers, require full-state measurements that may not be possible due to insufficient sensor numbers and/or sensor faults.…”