Marine Robotics

—We present a classification framework to detect underwater terrain deformations commonly caused by marine species in real time during AUV surveys. The method uses two classifiers in a hierarchical manner to overcome the fact that there are no substantial datasets in the literature about underwater terrain and the creation of one would involve a great consumption of human and technological resources. The first classifier based on Haar cascades, scans the image from an AUV stereo camera and detects all possible candidates of interest. Then, a Multi-Descriptor Random Forest is used to classify these candidates according to which species is more likely to have caused the associated terrain deformation. This classifier is able to integrate multiple descriptors to ensure the robustness of the system despite the vast amount of image distortions that happen underwater. The performance of the method is shown during a multiple AUV survey mission, where the Camera Vehicles follow the underwater ground up close. A comparison of the framework's output with the one from marine biologists exemplifies the accuracy of the system and its usefulness while supporting activities such as marine population monitoring to preserve nursery areas.

—This letter presents the design and potential impact of the developed Research Oriented Underwater Glider for Hands-on Investigative Engineering (ROUGHIE). The ROUGHIE is an open-source, highly-maneuverable, and low-cost vehicle that enables rapid development and testing of new hardware and software. ROUGHIE is an internally actuated glider capable of performing steady sawtooth glides in shallow water down to 3 meters, tight turns with a minimum radius of 3 meters, and a minimum endurance of 60 hours. The novelty of the work is twofold: 1) a rail-based design to facilitate modularity and ease of assembly and 2) an effective internal rotary mass mechanism to increase maneuverability and perform tight turns. The ROUGHIE design strategically uses 3D printed plastic parts in low stress situations which allows extreme design flexibility and enables tightly packed modules that can be easily customized.

O presente livro – O Mar no Futuro de Portugal: Ciência e Visão Estratégica – é um
dos resultados do projecto de investigação “A Extensão da Plataforma Continental
Portuguesa: Implicações Estratégicas para a Tomada de Decisão”, realizado no quadro do
Centro de Administração e Políticas Públicas do Instituto Superior de Ciências Sociais e
Políticas da Universidade de Lisboa, em parceria com a Marinha Portuguesa e a Esri-
Portugal, Sistemas de Informação Geográfica, S.A., financiado pela Fundação para a Ciência
e Tecnologia.

O Mar configurou Portugal. Na nossa História manteve presença constante como factor
de desenvolvimento nacional, como via de acesso a novas terras, novas gentes, novos produtos, novos negócios. Há quarenta anos, o 25 de Abril causou uma mudança estrutural na
posição geopolítica de Portugal e consequentemente no nosso conceito estratégico nacional.
Este conceito, desestruturado e indefinido durante cerca de uma geração, tem vindo a reconfigurar-se desde os anos 90 do século passado no sentido de uma reorientação nacional para o Mar, tendo a Expo 98 sido um marco desse movimento.

Hoje há ainda muito mais discurso que acção, mais palavras que realizações. Mas
estamos a ser convocados, desafiados para uma resposta digna da nossa História de nove
séculos e do nosso extraordinário feito dos Descobrimentos.

O processo de extensão da plataforma continental portuguesa, submetido formalmente
em 11 de Maio de 2009 à Comissão de Limites da Plataforma Continental das Nações
Unidas, veio de certo modo agitar a consciência marítima dos portugueses, e a Universidade
não deixou de ser alvo dessa agitação na interacção quotidiana que congrega professores e
estudantes preocupados com o presente e futuro de Portugal.

O Mar no Futuro de Portugal: Ciência e Visão Estratégica é pois um trabalho multidisciplinar
em que se cruzam história, economia, geografia, ecologia, biologia, gestão, relações internacionais, intelligence, prospectiva, sistemas de informação geográfica, cibersegurança, estudos estratégicos e robótica subaquática, numa composição de tempo tríbio: o
futuro de Portugal vislumbrado e projectado no presente em função do passado e da conjuntura.

In this paper we present a photogrammetry-based approach for deep-sea underwater
surveys conducted from a submarine and guided by knowledge-representation combined with a
logical approach (ontology). Two major issues are discussed in this paper. The first concerns
deep-sea surveys using photogrammetry from a submarine. Here the goal was to obtain a set
of images that completely covered the selected site. Subsequently and based on these images,
a low-resolution 3D model is obtained in real-time, followed by a very high-resolution model
produced back in the laboratory. The second issue involves the extraction of known artefacts present
on the site. This aspect of the research is based on an a priori representation of the knowledge
involved using systematic reasoning. Two parallel processes were developed to represent the
photogrammetric process used for surveying as well as for identifying archaeological artefacts
visible on the sea floor. Mapping involved the use of the CIDOC-CRM system (International
Committee for Documentation (CIDOC)—Conceptual Reference Model)—This is a system that has
been previously utilised to in the heritage sector and is largely available to the established scientific
community. The proposed theoretical representation is based on procedural attachment; moreover, a
strong link is maintained between the ontological description of the modelled concepts and the Java
programming language which permitted 3D structure estimation and modelling based on a set of
oriented images. A very recently discovered shipwreck acted as a testing ground for this project; the
Xelendi Phoenician shipwreck, found off the Maltese coast, is probably the oldest known shipwreck
in the western Mediterranean. The approach presented in this paper was developed in the scope
of the GROPLAN project (Généralisation du Relevé, avec Ontologies et Photogrammétrie, pour
l'Archéologie Navale et Sous-marine). Financed by the French National Research Agency (ANR)
for four years, this project associates two French research laboratories, an industrial partner, the
University of Malta, and Texas A & M University.

This paper presents a novel roll mechanism and an efficient control strategy for the roll and pitch of internally actuated autonomous underwater vehicles (AUVs) including most underwater gliders (UGs). The proposed design and approach increases maneuverability which is essential for operating in shallow water or crowded harbors. The design is implemented on Michigan Tech's research UG ROUGHIE (Research Oriented Underwater Glider for Hands-on Investigative Engineering) and the performance is validated. The experimental results demonstrate that ROUGHIE is capable of tight turn radii down to approximately twice the vehicle length in shallow water.

This article describes the technical challenges of stabilizing and conserving 25,000 lb. (12.5 tons) of Apollo-era (1969–1972) Saturn V rocket engine parts that were recovered off the coast of Florida in 2013. After more than 40 years on the floor of the Atlantic Ocean, the engines had suffered extreme levels of deterioration and corrosion. Treatment was accomplished by taking a deliberate, archaeological object–based treatment approach for these composite objects that are both modern technological marvels and marine archaeological artifacts. The article describes the archaeological treatment approach adopted and the results of selected analytical work undertaken to understand the materials of construction and the deterioration processes.

This paper presents a decentralized coordinated strategy for multi-robot patrolling missions. Patrolling is here interpreted
within the framework of the sampling problem. To be applied in practice, several realistic constraints and the time/spatial variance
of the information are explicitly taken into account. The proposed approach is well rooted in the concepts of Voronoi tessellations
and Gaussian Processes. Each robot, based only on local information, computes the next point to visit according to a given
performance criteria. Numerical simulations and experiments involving three autonomous marine surface robots in a harbour
scenario at the Parque Expo site in Lisbon, Portugal, are presented.

Accurate prediction of acoustic communication performance is an important capability for marine robots. In this paper, we propose a model-based learning methodology for the prediction of underwater acoustic communication performance. The learning algorithm consists of two steps: i) estimation of the covariance matrix by evaluating candidate functions with estimated parameters; and ii) prediction of communication performance. Covariance estimation is addressed with a multi-stage iterative training method that produces unbiased and robust results with nested models. The efficiency of the framework is validated with simulations and experimental data from field trials. The field trials involved a manned surface vehicle and an autonomous underwater vehicle.

This paper provides a study on the development and the use of a small autonomous surface vehicle (ASV) that automatically follows programmed mission transects, while measuring sensor outputs along the tracks. It discusses the mechanical construction of the ASV, the distributed architecture of controller area network (CAN)-based nodes for science and vehicle payloads, highspeed radio-frequency (RF) communications, the performance of the heading autopilot, global positioning system (GPS)-based guidance algorithm, and the mission programming technique. The field trials of the ASV, performed off the coast of Goa, India, are focused on retrieving the 2-D spatial distribution of surface chlorophyll, which is one of the useful parameters in characterizing the nature of calibration-validation (CALVAL) sites for ocean remote sensing needs. A further benefit of ASVs is that they can be built at a low cost and used in monitoring applications of diverse coastal ecosystems.