In-flight actuator failure recovery of a hexrotor via multiple models and extended high-gain observers

TL;DR

This paper presents a control strategy for a hexrotor UAV that can quickly identify and recover from actuator failures during flight by using multiple models and extended high-gain observers, accounting for disturbances and modeling errors.

Contribution

It introduces a novel multiple-model, multiple EHGO-based output feedback control approach for in-flight actuator failure recovery in hexrotors, with theoretical analysis and experimental validation.

Findings

Effective failure detection and identification within seconds

Successful recovery from actuator failure in simulations and experiments

Robustness to external disturbances and modeling errors

Abstract

We study an in-flight actuator failure recovery problem for a hexrotor UAV. The hexrotor may experience external disturbances and modeling error, which are accounted for in the control design and distinguished from an actuator failure. A failure of any one actuator occurs during flight and must be identified quickly and accurately. This is achieved through the use of a multiple-model, multiple extended high-gain observer (EHGO) based output feedback control strategy. The family of EHGOs are responsible for estimating states, disturbances, and are used to select the appropriate model based on the system dynamics after a failure has occurred. The proposed method is theoretically analyzed and validated through simulations and experiments.