MOQESM'2020
Robotics for Ocean Observation

Simon Rohou

Enseignant-chercheur, ENSTA-Bretagne

Il travaille principalement sur le calcul par intervalles de trajectoire.

Frédéric Plumet

Enseignant-chercheur, ISIR, Paris

Il travaille principalement sur la commande des robots voiliers.

Vincent Creuze

Enseignant-chercheur en robotique sous-marine au LIRMM (CNRS/Univ. Montpellier)

Il travaille sur la perception et la commande, appliquées aux robots sous-marins dans le domaine de l'archéologie et de la biologie

Luc Jaulin

Professeur en robotique

Professeur in ocean robotics. He works on interval computation with applications to autonomous underwater navigation.

Annick Billon-Coat

Secrétaire de laboratoire

Elle organise MOQESM pour la quatrième fois. Elle organise de nombreuses conférences qui se tiennent à Brest comme SWIM, ICOURS, etc.

Stéphane Imbert

Doctorant

With : Christophe Laot, Abdel-Ouahab Boudraa, Jean-Jacques Szkolnik

Affiliation: IMT Atlantique et Ecole Navale

AIS Relay for Autonomous Underwater Vehicle using an Adaptive Bit Rate Multi-Carrier Spread Spectrum Modem

Autonomous Underwater Vehicles (AUV) are commonly used in research and military sea applications. Therefore, AUVs are becoming part of the ocean navigation systems. To calibrate their navigational system by GPS, AUVs must regularly surfaced, operation during which collisions with vessels can occur. For security purpose, communicating the locations of boats to AUVs is required.
In this presentation, a communication system is developed to gather vessels positions using the AIS system and relay this information to AUVs. By having a buoy or a boat at the surface, it is possible to collect data about the surrounding ships and forward these data to the AUV fleet. Since the bit rate of underwater communication is way lower than the AIS one especially at large distances, reducing the payload for relay purpose is required. By removing irrelevant AIS data and compressing positional ones, the AIS payload can be reduced saving 182 bits on each 256 bits message.
The proposed communication system is a multi-carrier spread spectrum (MC-SS) downlink modem broadcasting the positions of vessels towards the AUVs fleet. MC-SS combines spreading and multi-carrier signal. Using variable length spreading sequences and OFDM, this communication system creates a flexible and robust solution thanks to the frequency diversity and processing gain to transmit at various distances.
The modem was experimented with the Watermark channel simulator considered as a realistic test benchmark for underwater communications. Results show the effectiveness of the spreading factor to improve the error rate at low SNR.

Luc Jaulin

Roboticien

Ocean exploration with underwater robots

Man carries out many long and perilous missions in the ocean, such as the transport of goods, the construction of offshore infrastructures, the search for wrecks, etc. Because of the difficulty, cost and dangerousness of these missions, marine robots are increasingly used. Nowadays, they are mainly used for taking measurements, constructing underwater maps, searching for mines or studying marine currents. In order to avoid collisions with surface traffic, robots are generally asked to stay underwater and never to resurface. Localization becomes difficult and often even impossible due to the absence of landmarks and the non-functioning of GNSS. By mimicking the techniques of ancient navigators, or marine animals (such as sea turtles), we will show that a submarine robot can explore a very vast environment and return to its initial position without being able to geolocalize itself.

Simon Rohou

Roboticien

Underwater Localization with Indistinguishable Landmarks

A realistic situation encountered in underwater robotics is the one of a robot evolving in an environment made of indistinguishable landmarks. The rocks that can be observed on the seafloor represent strong positioning data if we provide the robot with a prior map of the environment. The difficulty however is to identify the landmarks in the map, which cannot be done only by image processing. Indeed, the observations of rocks are view-point dependent and the sonar images are noisy, which makes it difficult to distinguish one rock from another only from image processing.
Furthermore, the position of the robot may be lost during a diving phase, which obliges us to consider unknown initial position.
We propose a constraint propagation approach to solve simultaneously the problems of identifying the rocks and estimating the position of the robot.
The efficiency of the method is shown on an actual experiment involving an autonomous underwater robot and data from a side scan sonar.

Quentin Delplanque

ELWAVE (Nantes, France)

6th Sense for Underwater Vehicle

Nowadays, real-time 360° “all-around” perception is a non-achieved key capability for safe and efficient operations of underwater remote (ROV) or autonomous underwater vehicles (AUV). The navigation in low or non-visibility, the obstacle avoidance in cluttered field, the close approach of infrastructure, the tracking of buried object are very complex and challenging tasks that an innovative sensor may simply overcome.
ELWAVE, a company located in Nantes, France, is the first and unique company to develop and commercialize revolutionary real-time 360° subsea sensors based on ‘active electrolocation'. ELWAVE valorizes more than 10 years of research works from the biorobotics laboratory of Atlantic Mines-Telecom Institute (Nantes, France).
‘Active electrolocation' is the sensory mode used by some fishes able to generate electric field and living in tropical muddy and congested waters. Inspired from this unique biomimetic technology, ELWAVE's sensors mounted on underwater vehicles generate a weak electromagnetic field and measure its modulations. Algorithmics and artificial intelligence processing then enable the detection, the location and the characterization (size, shape, type of material) of the objects.
ELWAVE technology is efficient in simple and any degraded operating situations, allows the detection in water and into sediments of metallic and non-metallic objects and living organisms.
This capability developed by ELWAVE is a major breakthrough for underwater robotics adding a « 6th Sense » to underwater vehicles.

Joris Tillet

Doctorant en robotique, ENSTA-LabSTICC

Guaranteed underwater localization with scanning sonar

To localize a robot in a well known environment containing walls, like pools or harbors, seems to be relatively easy with a scanning sonar. However, most of the time, the data given by the sonar contains several echoes corresponding to the walls as expected, but also to the surface or the ground, to multi echoes and other perturbations. So the convergence, the precision, and the reliability of the localization highly depend on which information is used from sonar data.
The method proposed here consists in using only reliable information deduced from sonar data in the form of constraints. The area of possible localization for the robot is then contracted in order to always fit with the desired constraints. With this method, we can guarantee that, provided that some realistic assumptions are fulfilled, the robot is never outside the computed area.

Pierre-Yves Morvan

Localisation, iXblue, Brest

Delph Subsea Positioning Software - iXblue's innovative software solutions for subsea positioning

Improving operational efficiency is a recurring challenge for subsea operations. Throughout the life of a field, from construction up to decommissioning, several subsea vehicles will be deployed to cover various tasks such as pipeline and structure installation, maintenance or repair. An ROV or AUV assigned to a specific task will require multiple positioning sensors (LBL, USBL, INS…) to complete its mission. Defining the “good enough” subsea positioning strategy, i.e. to ensure a minimum accuracy without compromise on safety, can be a complex exercise. For instance, an overestimation of the LBL transponders required will directly induce vessel time and finally costly operations. On the other hand, a certain level of positioning redundancy may be requested for a vehicle operating close to a subsea asset in production.
To ease the design and monitoring of a subsea vehicle navigation, iXblue has developed an integrated solution. Not only has the company broadened its product range with the new intelligent Canopus LBL Transponder and the new generation Ramses transceiver, but with Delph Subsea Positioning Software, iXblue now provides a complete integrated solution for subsea positioning that goes a step further by bringing significant efficiency. Divided in 4 modules (LBL Array Planning, Navigation Simulation, Operations, DelphINS) with an intuitive user interface, Delph Subsea Positioning (DSP) is an integrated software suite for the preparation, the operation and the post-processing of iXblue positioning devices (USBL, LBL and INS).

João Borges de Sousa

Assistant professor

With: Daniel Alcaraz, Gianluca Antonelli, João Borges de Sousa, Massimo Caccia, Gerard Dooly, Niamh Flavin, Achim Kopf, Martin Ludvigsen, Jan Opderbecke, António Pascoal, Matthew Palmer, Roberto Petroccia, Pere Ridao, Antonio Vasilijević, Sen Wang

Affiliation: LSTS - Porto University (Porto, Portugal)

EUMarine Robots, a Marine robotics research infrastructure network: Mid-term report

The H2020 Marine robotics research infrastructure network (EUMR) mobilizes a comprehensive consortium of key European institutions involved in the area of marine robotics to open up key facilities to researchers worldwide by fostering joint R&D and providing end-users access to an integrated world-class marine robotics infrastructure (RI). This paper reports on the three types of activities carried out in EUMR: Transnational Access (TNA), Joint Research (JRA) and Networking Activities (NA). TNA offers access to infrastructures of the 15 project partners. These include a variety of autonomous underwater, surface and air vehicles, ships and testbeds. Access is granted through competitive calls. The first two calls in October 2018 and August 2019 elicited a total of 57 eligible applications from Europe, Asia, and North America, with 50 projects being approved. JRA focuses on developing advanced marine robotic systems and technologies and improving existing infrastructures. This involves 6 tasks:
i) Advanced vision, acoustic, and manipulation systems for automated inspection and intervention operations,
ii) Cooperative navigation and control of networked vehicles for increased autonomy at sea,
iii) Hybrid acoustic-optical underwater communication networks for next-generation cooperative systems,
iv) Advanced Systems for Under-Ice operations,
v) Enhanced underwater LARS system and
vi) Cooperative human-marine robot systems.
NA included the organization of the 2018 and 2019 editions of the Breaking the Surface workshop, the PLOCAN glider school and the EMRA annual conference.

Delphine Mallet

Directrice-fondatrice chez VISIOON

With : Marion Olivry, Sophia Ighiouer, Laurent Wantiez

Affiliation: VISIOON – 2 rue Marcel Creugnet 98800 Noumea, New Caledonia.

Non-destructive monitoring of soft-bottom fishes and habitats using a standardized remote un-baited 360° video sampling method.

Soft-bottoms habitats are used as a nursery, a feeding ground or a transit area by fish. However, these fish assemblages are poorly known because of the lack of a standardized and non-destructive sampling method. We developed a remote un-baited 360° video sampling method to monitor the diversity, abundance and structure of soft-bottom fish and their habitat. The technique uses a low-cost high definition camera enclosed in a waterproof housing, fixed on a tripod and set on the bottom from a boat. To assess the efficiency of this method, 534 videos were recorded in the Southwest Lagoon of New Caledonia (60 km²). The technique can sample bare, vegetated or mixed soft-bottoms. 172 fish species (37 families) were recorded. Turtles, dolphin, sea snakes were also observed. The results are consistent with the known characteristics of the lagoon soft-bottom of New Caledonia. The method is efficient to identify the different habitats and the structure of fish assemblages. We provide general recommendations to use this method and abacus giving the proportion of the theoretical total specific richness sampled according to the number of stations or the duration of the recording.

Markus Lindh

Marine biologist

With: Johan Stål

Affiliation: Swedish Meteorological and Hydrological Institute (Gothenburg, Sweden)

A picture is worth a thousand data points: Making videos and images from marine environmental monitoring available to all

A picture is worth a thousand words” is a common proverb to describe the advantage of using a picture over words in advertisement. In marine environmental monitoring, video and images are often the foundation of data, where one video or image can be worth thousands of data points. Yet, there is a fundamental gap between data sampling and data access where video and image data from the marine environmental monitoring community needs to be made publicly accessible with good metadata descriptions. SMHI have developed a state-of-the-art system for archiving and publishing image and video data from marine environmental monitoring. Here, we will present our solution for a system that is capable of receiving, archiving, quality controlling and packaging data. Video and image data collected at SMHI include monitoring of epibenthos, phytoplankton and megafauna (seals and harbour porpoise). We are using a metadata description applied from the INSPIRE directive and include the use of digital object identifiers (DOI) for published data packages so that data is findable. All data, including metadata, goes through a high-throughput quality control and administration system developed in-house at SMHI with open source code (MIT license). The data will also be made available to ongoing international projects such as JERICO-RI and for data aggregators such as EMODnet, SeaDataCloud and ICES. We anticipate that the data will be used by the regional sea conventions and potentially also the European Environmental Agency

Franck Florin

Engineer

With: François Effa et Damien Goaper

Affiliation: THALES (Brest, France)

High Frequency Acoustic Channel Modeling and Experiment in Shallow Waters

Acoustic communication is essential for Autonomous Underwater Vehicles (AUV) in order to exchange data with the sea surface for command and control. Communicating with an AUV in shallow water may however be challenging because of the channel distortion introduced by sound propagation. Underwater acoustic channel models provide a tool for predicting the performance of communication systems, and are essential for system simulation. In this paper, we describe a channel model of the 10-50 kHz frequency band which incorporates physical laws of acoustic propagation (attenuation, absorption, bottom/surface reflections), as well as the effects of random local variations (diffusion and reverberation).
The model is validated using real data obtained from an experiment in North-Atlantic shallow waters. The experiment is based on the LMAIR (Laboratoire Marin d’Acoustique et d’Imagerie de la Rade) equipment. This equipment was supported by the European Union regional development funds and financial contributions of Région Bretagne, Département du Finistère, and Brest Métropole, under Grant Contrat de Plan Etat Région (CPER) IROMI. We introduce the sound propagation model in shallow waters and we describe the experimental equipment. Then the presentation details the methods used to measure the parameters of the model. The experimental results are addressed with a focus on the limitations.

Dorothée James et Antoine Mury

Ingénieure d'étude

With: Antoine Collin, Thomas Houet, Nolwenn Le Poulain

Affiliation: EPHE, PSL Université Paris, LETG (Dinard, France)

Coupling UAV multispectral imagery and neural network to model the seagrass coastal protection service

Seagrasses are sensitive to global changes. Lying on subtidal and intertidal areas, seagrasses provide ecosystem services as a support for biodiversity, recreation or coastal protection. Highlighted at the international scale by Intergovernmental Oceanographic Commission and International Platform on Biodiversity and Ecosystem Services and also by national institution, the study and monitoring of these specific ecosystems is crucial in the current global changes. Seagrass habitat mapping is carried out using active SoNAR, LiDAR technology, or passive satellite imagery. The low temporal resolution of these remote sensing methods can be overcome, today, by low-cost unmanned aerial vehicle (UAV), provided with ultra high spatial but also very high temporal resolution (UHSR and UHTR, respectively).
The aim of this study is to propose an innovative methodology to model the ecosystem protection service induced by seagrasses, in 2D, and with UHSR, by coupling the UAV multispectral (MS) imagery, its by-products, and neural network (NN) learner. This consists of a 4-step method:
1) in situ wave measurement through pressure sensors recording at UHSR and UHTR, and calculation of wave attenuation values between measurement stations,
2) UAV MS imagery acquisition at UHSR,
3) quantification of the UAV predictors’ (MS imagery data and by-products) contribution to the observed wave attenuations, and
4) spatially-explicit modeling using an artificial NN. The best 4 predictors from the MS imagery are used for the final modeling of the protection service offered by seagrasses.

Julien Damers

Doctorant, Kopadia

With : Corentin Jegat

Affiliation: Kopadia S.A.S, Lab-STICC, France

AUV navigation using isobath

This presentation is about AUV navigation using isobath. Several techniques have been developed to address the problem of localisation and navigation underwater with the emergence of Autonomous Underwater Vehicle (AUV) technology. Some use state-of-the-art thus costly Inertial Navigation System (INS) and Doppler Velocity Log (DVL) to limit drifting errors. Others utilize an embedded bathymetry map and sonars to perform Terrain Relative Navigation (TRN) algorithms to correct drifting errors. Alternating Landmark Navigation (ALN) has been investigated to remove the need of an embedded map for navigation but requires several AUVs to be used. At Kopadia we performed AUV navigation using isobath. An isobath is a set of connected points which all have the same depth below the water surface, may it be ocean, sea or lake. It is easily measurable with low-cost sensors such as a simple depth sensor, an echo-sounder and an INS to control the attitude of the vehicle. This allows the design of a low-cost AUV which is suitable for the case of a swarm of identical AUVs. We also present future work to perform localization using isobath and adapt this navigation method for a swarm of AUVs aiming at exploring a wide area.

Guillaume Labbé-Morissette

Researcher

Affiliation: CIDCO, Rimouski, Canada

Unsupervised detection of underwater objects in sidescan sonar imagery

The problem of finding underwater objects is a recurring issue in many fields, such as hydrography, search and rescue (SAR), underwater archaeology, marine sciences, and many more. Unfortunately, the hostile nature of the underwater environment for human beings, the weak penetration of light and the difficulty of acquiring high-quality images, along with the high mobilizing costs of SCUBA or remotely-operated solutions only makes this endeavour harder to fulfill. The shift towards autonomous vehicles equipped with acoustic imaging technology as force multipliers during such operations brings along new problems with the multiplication of data sources, such as an exponential increase in required resources for post-processing the data. Thus, this presentation details a new method to recognize and detect underwater objects in real-time sidescan sonar data imagery streams, with case-studies of applications for underwater archeology, and ghost fishing gear retrieval.

Nathalie Olivier

Engineer

Affiliation: iXblue, Saint-Germain-en-Laye, France

Test results before the deployment of a subsea geodetic monitoring system

Geodetic networks at sea are necessary to monitor active faults and the long term displacement of tectonic plates. iXblue has developed a new integrated subsea monitoring system: Canopus The Canopus transponders are enable to regularly measure precisely the distance between the transponders that are in acoustic line of sight. The measurement are stored in a memory inside each beacon and can be collected from surface using acoustic modem. In collaboration with the IUEM, and in the framework of ERC Focus project, 8 Canopus beacons are going to be deployed at each side of the North Alfeo Fault in Sicilia for a 4 years monitoring program. To prepare the deployment, a first experiment took place in Brest Bay in July 2019. Thanks to Delph subsea positioning software, simulations enable to confirm acoustic line of sight between beacons considering the local bathymetry, the sound velocity profile and the height of the transponders above the seabed.

Pierre-Jean Bouvet

Lecturer

Affiliation: ISEN Yncréa Ouest, Brest, France

With : Philippe Forjonel, Yves Auffret

IROMI-LMAIR : an innovative network of instrumented platforms for marine and underwater technologies

The “Laboratoire Marin d’Acoustique et d’Imagerie de la Rade (LMAIR)”, in English “Maritime laboratory for acoustics and imaging of the roadstead of Brest” is an innovative research infrastructure, leaded by ISEN Brest Yncréa Ouest and funded within the frame of the state-region plan (CPER) called “Infrastructure de Recherche pour Observatoires Marins Innovants (IROMI) by the European Regional Development Fund (ERDF), the Brittany region, the Finistere department and Brest city. The LMAIR infrastructure consist of 3 relocatable marine platforms and a fixed pontoon situated in the roadstead of Brest within the Sea Test Base – Celadon premises, a non-profit organization that provides Land based and marine facilities for ocean science and technology. Produced by RTSYS company according to ISEN Yncréa Ouest specifications, each platform is energy self-sufficient owing to wind turbine and solar panels and is connected to the ISEN Yncréa Ouest labs (or other location) by using a 4G radio link through a Virtual Private Network (VPN) tunnel. The instrumentation includes an acoustic gondola with 5 hydrophones (including 1 wideband sensor) and one acoustic projector, electronics for underwater acoustic signals recording and amplifier for transmission signals, a weather station, GPS and a 360° camera.
The LMAIR system can be considered as an experimental laboratory at sea, available 24/7/365 for many research applications like maritime surveillance, passive acoustic monitoring, underwater acoustic communication, positioning and tomography.

Henrique Fagundes Gasparoto

Postdoc

Affiliation: France, ENIB, ENSTA-Bretagne

Modelling, Optimisation, and Design of a New Reconfigurable Magnetic Coupling Thruster for Underwater Robots

The use of reconfigurable thrusters on the development of new AUV architecture has grown up in the last years. With this type of thruster, it is possible to design underwater robots with changeable thruster architectures. This work shows the development process of a new propulsion system for submarine vehicles (robots), which can guarantee complete water-tightness, greater manoeuvrability, and better efficiency. The perfect water-tightness is ensured using magnetic couplings, which allow the torque transmission to the outside of the robot, without having holes and mechanical seals on its hull. Greater manoeuvrability is achieved through the reconfigurable propulsion system, which allows the propeller reorientation, thus ensuring more degrees of freedom per each thruster, which reduces the total number of required thrusters to drive and steer the vehicle, thereby increasing its efficiency. This system is called reconfigurable magnetic coupling thruster (RMCT). To make it possible, innovative design is proposed with appropriate actuators, then it is modelled, optimised, detailed, fabricated and assembled. The new design is modelled parametrically considering its mechanical and magnetic behaviour, composing a digital prototype that is optimised. The parametric magnetic model uses the method that can be evaluated most quickly among the finite element method and the finite volume integration method. The optimisation process considers an evolutionary method, i.e. Genetic Algorithms. Finally, an optimal RMCT is achieved for the considered parameters. The executive project is carried out, fabricated (3D printed), and assembled.

Ornella Tortorici

PHD student

Affiliation: Université de Toulon, COSMER-IM2NP

Using Vortex Simulator to validate the control of a tethered ROV

Underwater cables are often used to link ROV to a control unit on the surface. They transmit data in both directions, they can power supply the ROV and they provide a safety link to retrieve the ROV in case of failures.
However, when not managed properly, underwater cables have drawbacks: They induce drag force, their inertia can slow down the ROV, they limit its workspace, they can get caught on something or drag on the seabed. All of these reduce ROV maneuverability.
Our main objective is to actively manage the cable of a ROV in real time to limit hazards related to the environment. The knowledge of the cable shape will then help us to estimate the ROV position. This presentation will introduce a way to instrument the cable to observe its behavior and control it. It will also describe in details the use of Vortex software to simulate the complete system and to analyze its behavior under different controls.