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Marine robotics is a complex field with a potentially high demanding logistics and high deployment cost. This is a barrier to many research groups. On the other hand, some research groups have substantial equipment and infrastructure that are typically underutilized. The push for sharing infrastructures was recently accentuated due to the COVID-19 pandemic. In particular, remote access experiments became the norm during the lockdown periods. LABUST completed new infrastructure during the COVID-19 pandemic and prepared it for state-of-the-art remote access from anywhere in the globe. This is important both for research and educational purposes. This article describes the infrastructure, equipment, and methods used for implementing the remote access including the calibration procedures. It also reports on real remote access trials for different applications such as Autonomous ships, diver–robot interaction, and Remotely Operated Vehicle (ROV) pilots. These examples include both pool and at-sea remote trials, proving the capabilities of the infrastructure. [ABSTRACT FROM AUTHOR]

This paper describes an underwater acoustic sensor network consisting of a heterogeneous robotic swarm used for long-term monitoring of underwater environments. The swarm consists of a large number of underwater robots acting as sensor nodes with limited movement capabilities, and a few surface robots aiding them in accomplishing underwater monitoring scenarios. Main interactions between two types of robots include underwater sensor deployment and relocation, energy and data exchange, and acoustic localisation aiding. Hardware capabilities of each vehicle are described in detail. Inter-agent communication is split into two layers: surface and underwater communication. Surface communication utilises wireless communication using WiFi routers configured for decentralised routing. Underwater communication mainly uses acoustic communication which, when used within a large swarm, poses a challenging task because of high probability of interference and data loss. The acoustic communication protocol used to prevent these issues is presented in detail. Finally, more complex functionalities of the robotic swarm are presented, including several results from real-life experiments. [ABSTRACT FROM AUTHOR]

Noise prediction on board Ro-Ro passenger ship with a capacity of 145 cars and 600 passengers has been performed by means of the hybrid Statistical Energy Analysis (SEA). A general commercial noise analysis software Designer-NOISE is used. Basic issues related to noise on board ships are described, with particular emphasis to regulatory framework. An outline of the used software is presented together with ship technical data and noise source overview. Noise model is described in details and results are presented for selected compartments both without and with sound insulation. In addition to standard noise prediction output, a sensitivity analysis of noise levels with respect to some design parameters (wall thickness, insulation type and thickness, etc.) has been performed. Finally, conclusions on noise performance of a ship are drawn. [ABSTRACT FROM AUTHOR]

For metrizable continua, there exists the well-known notion of a Whitney map. If X is a nonempty, compact, and metric space, then any Whitney map for any closed subset of 2X can be extended to a Whitney map for 2X [3, 16.10 Theorem]. The main purpose of this paper is to prove some generalizations of this theorem. [ABSTRACT FROM AUTHOR]

For metrizable continua, there exists the well-known notion of a Whitney map. Garcia-Velazquez extends the definition of Whitney map for C(X), where X is an arbitrary continuum (not necessarily metrizable). He also shows that the examples he considers do not admit such generalized Whitney maps. In this paper we shall investigate the properties of continua which admit such generalized Whitney maps. [ABSTRACT FROM AUTHOR]

This paper presents a novel autonomous environmental monitoring methodology based on collaboration and collective decision-making among robotic agents in a heterogeneous swarm developed within the project subCULTron, tested in a realistic marine environment. The swarm serves as an underwater mobile sensor network for exploration and monitoring of large areas. Different robotic units enable outlier and fault detection, verification of measurements and recognition of environmental anomalies, and relocation of the swarm throughout the environment. The motion capabilities of the robots and the reconfigurability of the swarm are exploited to collect data and verify suspected anomalies, or detect potential sensor faults among the swarm agents. The proposed methodology was tested in an experimental setup in the field in two marine testbeds: the Lagoon of Venice, Italy, and Biograd an Moru, Croatia. Achieved experimental results described in this paper validate and show the potential of the proposed approach. [ABSTRACT FROM AUTHOR]