Estimativa da Velocidade do Vento via UAV Sem Sensor de Velocidade do Rotor

Abstract

This paper considers a sliding mode-based control scheme (SSC) for a class of uncertain nonlinear systems with relative degree one, generating a smooth and chattering-free control effort. The problem of trajectory tracking for a UAV is considered, with a control configuration composed by a cascade of an internal loop (speed control) and an external one (position SSC control). The objective is to generate an estimate of the wind speed without onboard wind speed sensors. In general terms, closed-loop robustness can be observed with respect to disturbances caused by wind in trajectory tracking. The proposed scheme is based on the estimation of the aerodynamic drag without using motor speed sensors. This scheme allows the estimation of the input disturbance faced by the external sliding mode controller with sufficient accuracy such that the wind speed can subsequently be estimated using a known analytical model for aerodynamic drag. Simulation results with real wind data collected with an anemometer illustrate the performance of the proposed wind speed estimation scheme.