Hovering Analysis of a Tethered Multirotor under External Disturbances

Davi Ferreira de Castro¹; Igor Afonso Acampora Prado¹; Mateus de Freitas Virgílio Pereira¹; Davi Antônio dos Santos¹; José Manoel Balthazar¹; Maurício Andrés Varela Morales¹

¹ Instituto Tecnológico de Aeronáutica (ITA)

doi:10.20906/CPS/CON-2016-1210

Resumo

Multirotor Aerial Vehicles (MAVs) have been the subject of many academic studies and have attracted a lot of attention from industry in recent years. MAVs have flight capabilities such as hovering, Vertical Take-Off and Landing (VTOL) and agile maneuvering capability, which cannot be achieved by conventional fixed wing aircraft. However, such vehicles have limited autonomy, which results in flights of at most some minutes. A sub-category of aerial vehicles is tethered MAVs, which are anchored at a fixed point by a cable. While this limits their motion, it can also works as a power line, providing electrical power to the vehicle and enhancing its flight autonomy. This paper presents a hovering analysis of a tethered multirotor under external disturbances. The vehicle is an octocopter with flat configuration. The cable consists of a series of elastic elements with the mass elements lumped at the nodes. The controller is based on a saturated state feedback control. The model was evaluated through numerical simulations using MATLAB/Simulink. The vehicle performed a hover flight and was subjected to external disturbances in order to emulate ambient wind. The results for the tethered MAV were compared with the MAV flying freely without cable. The tethered MAV presents improved hovering capability when compared with the vehicle without cable, due to the tension exerted by the cable, which provides a better robustness to exogenous perturbations.

Palavras-chave: Multirotor Aerial Vehicles; Tethered Multirotor; Modeling