The integration of precise landing capabilities into UAVs is crucial for enabling autonomous operations, particularly in challenging environments such as the offshore scenarios. This work proposes a heterogeneous perception system that incorporates a multimodal fiducial marker, designed to improve the accuracy and robustness of autonomous landing of UAVs in both daytime and nighttime operations. This work presents ViTAL-TAPE, a visual transformer-based model, that enhance the detection reliability of the landing target and overcomes the changes in the illumination conditions and viewpoint positions, where traditional methods fail. VITAL-TAPE is an end-to-end model that combines multimodal perceptual information, including photometric and radiometric data, to detect landing targets defined by a fiducial marker with 6 degrees-of-freedom. Extensive experiments have proved the ability of VITAL-TAPE to detect fiducial markers with an error of 0.01 m. Moreover, experiments using the RAVEN UAV, designed to endure the challenging weather conditions of offshore scenarios, demonstrated that the autonomous landing technology proposed in this work achieved an accuracy up to 0.1 m. This research also presents the first successful autonomous operation of a UAV in a commercial offshore wind farm with floating foundations installed in the Atlantic Ocean. These experiments showcased the system's accuracy, resilience and robustness, resulting in a precise landing technology that extends mission capabilities of UAVs, enabling autonomous and Beyond Visual Line of Sight offshore operations.

Francisco Neves

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An intelligible step-by-step Reinforcement Learning (RL) problem formulation and the availability of an easy-to-use demonstrative toolbox for students at various levels (e.g., undergraduate, bachelor, master, doctorate), researchers and educators. This tool facilitates the familiarization with the key concepts of RL, its problem formulation and implementation. The results demonstrated in this paper are produced by a Python program that is released open-source, along with other lecture materials to reduce the learning barriers in such innovative research topic in robotics. The RL paradigm is showing promising results as a generic purpose framework for solving decision-making problems (e.g., robotics, games, finance). In this work, RL is used for solving a robotics 2D navigational problem where the robot needs to avoid collisions with obstacles while aiming to reach a goal point. A navigational problem is simple and convenient for educational purposes, since the outcome is unambiguous (e.g., the goal is reached or not, a collision happened or not). Thus, the intent is to accelerate the adoption of RL techniques in the field of mobile robotics. Motivate and promote the adoption of RL techniques to solve decision-making problems, specifically in robotics. Due to a lack of accessible educational and demonstrative toolboxes concerning the field of RL, this work combines theoretical exposition with an accessible open-source graphical interactive toolbox to facilitate the apprehension. This study aims to reduce the learning barriers and inspire young students, researchers and educators to use RL as an obvious tool to solve robotics problems.