Experimental tests of hybrid VTOL unmanned aerial vehicle designed for surveillance missions and operations in maritime conditions from ship‐based helipads

Abstract

This article presents research on a hybrid vertical take‐off and landing (VTOL) unmanned aerial vehicle (UAV) supported by a relative positioning system, enabling the deployment of autonomous missions from ship‐based helipads in maritime conditions. A crucial issue to be solved is ensuring precise positioning of the UAV relative to the landing pad in the take‐off and landing phases. To achieve this, an extended Kalman filter (EKF) is implemented on the UAV's onboard computer, which integrates the positioning data from the UAV's global navigation satellite system receiver and the positioning data of the landing pad broadcast by the landing pad navigation station (LNS). The EKF estimates both the absolute and relative position of the UAV, which are required for autonomous take‐off and landing on the moving landing pad. In unfavorable weather conditions, EKF also uses data from an optional local positioning system to keep the accuracy within the range 1–3 m. The research was concluded by experimental verification during a ferry cruise over the Baltic Sea. During the research, the VTOL UAV performed two fully autonomous flight missions at the range about 1 km from the moving ferry in international waters. Each of them ended with a successful landing back on the helipad with an accuracy matching its required level, which was already achieved in the previous research carried out in inland conditions. Data recorded during real flights confirm that the developed system, consisting of a hybrid VTOL UAV and a LNS, is ready to be utilized in autonomous missions at sea. Factors having a critical impact on the safety of use of the VTOL UAV in marine conditions were also identified, which were not observed during the research in inland conditions, and are related directly to turbulence around the landing pad.

Multirotor Motor Failure Detection with Piezo Sensor

“…A significant part of UAV propulsion system failures concerns precisely such situations where we do not have a complete loss of rotational speed. The authors of this article dealt with many similar situations during the implementation of the last research and the development of the project, which concerned the use of UAVs of the VTOL type in collision-free navigation of sea-going vessels [ 22 , 23 ]. In this project, one of the aircraft used was the hybrid VTOL (quadwing airframe).…”

“…The Albatross was developed as a part of a maritime project related to maritime safety [ 22 ]. That is why it was equipped with inflatable airbags to prevent drowning in the event of an unexpected landing on the water.…”

An Innovative UAV with VTOL Capabilities

“… Moore-Penrose approach minimizes the quadratic norm of the vector of calculated ωi 2 . This is a very useful properties since this produce an optimization also of energy consumptions of the drone as also stated by recent works [55] in which this property is exploited to improve efficiency and autonomy of drones.…”

“…Proposed system is mainly devoted for marine operations [1] involving the usage of ship-based helipads, this is an application that is still the object of very recent studies [2] for its relevant industrial interest.…”

Asymmetrical Artificial Potential Field as Framework of Nonlinear PID Loop to Control Position Tracking by Nonholonomic UAVs

“…Position tracking is one of the most useful features of present unmanned aerial vehicles. It can be adopted in a variety of applications, starting from formation flights [ 1 , 2 , 3 ],through operations such as moving platforms [ 4 , 5 ], ending with visual feature tracking [ 6 , 7 ], such person tracking [ 8 ], which is common in commercial drone solutions (e.g., DJI). In each of them, the precision of keeping the desired position or distance from a moving reference point plays a crucial role.…”