Underwater Communications and the Level of Autonomy of AUVs

A Tale of Two Technologies
Autonomous underwater vehicles (AUVs) are a recurrent theme in maritime and offshore applications, and in particular those involving long and costly data-gathering operations such as hydrographic surveys. Challenging surveys like those required for search operations following an aircraft crash in the oceans and for mapping oil spills below the ice during Arctic operations demonstrate the need for flexible solutions that enable mapping in deep, remote and congested locations. AUVs provide flexibility by cutting the umbilical cord to the mother vessel. This implies the necessity for underwater communications and a high level of autonomy for the vehicle as well as interoperability... (read more)
2015-08-06 03:10:32

Staring at Waves – Knowing What’s Below

Optimisation of a Bathymetry Module within a Rip Current Prediction System
The dynamic appearance of offshore directed currents, mainly rip currents, during the summer season has led to several fatal incidents at the beach of Egmond aan Zee (The Netherlands) in the past. A rip current prediction system has been set up in order to avoid such incidents in the future. The occurrence and characteristics of rip currents depend strongly on subtidal bathymetries, hence detailed survey data is required for accurate predictions. ARGUS, the video monitoring system, was considered to provide the prediction system with precise, regularly updated bathymetry data. This is why the applicability and reliability of the ARGUS system... (read more)
2018-10-30 10:14:09

How to Simplify Survey Reporting

Wouldn’t it be great to work on a hydrographic project without spending a lot of time looking for all the elements needed for a professional report? This was what Sanyal Sunil had in mind when he developed SURge, a digital tool to simplify survey reporting. Wouldn’t it be great to work on a hydrographic project without spending a lot of time looking for all the elements needed for a professional report? This was what Sanyal Sunil had in mind when he developed SURge, a digital tool to simplify survey reporting. Hydrographic survey reporting has always been a headache for surveyors in the field, as they have to spend a lot of time formatting the reports, finding the correct logos and diagrams, displaying observations schematically, and carrying out irrelevant calculations, all of which have to be neatly represented in the report but have nothing to do... (read more)
2020-02-24 02:03:38

Hydrographic Mapping is Critical for the Caribbean

It is a Service Provided Inconsistently by the Developed Nations
Considered paradise by the legions of tourists who visit each year, the Caribbean islands are developing states that struggle to maintain a delicate balance between economic expansion and environmental preservation. Hydrographic mapping, a critical element in achieving this equilibrium, has been a service provided inconsistently by the developed nations upon which many of the islands are still dependent. Affordable new geospatial technologies, however, offer Caribbean islands the opportunity to reduce their traditional reliance and assume greater control over their economies and natural resources. Considered paradise by the legions of tourists who visit each year, the Caribbean islands are developing states that struggle to maintain a delicate balance between economic expansion and environmental preservation. Hydrographic mapping, a critical element in achieving this equilibrium, has been a service provided inconsistently by the developed nations upon which many of the islands are still dependent. Affordable new geospatial technologies, however, offer Caribbean islands the opportunity to reduce their traditional reliance and assume greater control over their economies and natural resources. The islands of the Caribbean, collectively known as the West Indies, were colonized for centuries by seafaring... (read more)
2020-03-18 10:08:24

The Importance of Hydrography Establishing the Outer Limit of the Continental Shelf

Commander Alexander Tagore Medeiros de Albuquerque (retd) of the Brazilian?Navy is one of the outstanding hydrographers of the Directorate of Hydrography and Navigation (DHN) of the Brazilian Navy. DHN tasks include the delimitation of the national continental shelf in accordance with UNCLOS. Brazil and its hydrographers have contributed to the text of the UNCLOS since its first draft. It therefore seems appropriate that a Brazilian hydrographer now chairs the Commission. Hydro international was able to interview Mr Albuquerque and it is hoped that the readers shall appreciate not only the importance of the task of the Commission but also the... (read more)
2009-01-05 12:00:00

Integrated Mapping of Seabed Features

Dual use Hydrographic Surveys for Seabed Nature and Morphological Research
The Italian Navy, using survey vessel Ammiraglio Magnaghi and personnel from the “Istituto Idrografico della Marina” (IIM), in cooperation with ENEA Marine Environment Research Centre, surveyed the Levante Canyon system, located in the offshore area of “Cinque Terre”, eastern Ligurian Sea, NW Mediterranean. The purpose of the operation in the area depicted in figure 1 was on the one hand to collect the data necessary for the updating of nautical documentation and on the other hand to carry out scientific research on the seabed nature and specifically on deep coral banks. Italian Navy Ships are equipped with state-of-the-art equipment and... (read more)
2014-10-06 02:21:18

Mapping the Seafloor with Remote Sensing and Satellite Imagery

An Analysis of the Techniques and Benefits of These Methods
70% of the Earth is covered by water, but so far just 7% of it has been surveyed (Mars, Venus and the Moon are better surveyed). Hydrography as a science has changed dramatically since the first measurements were made by Alexander Dalrymple and James Cook with lead lines and sextants. Singlebeam echosounders were invented in the 1920s – a technology still used today for mapping the seafloor. This method of using echosounders can produce very high-resolution bathymetric data but the high operational costs and the slow working process make it economically unsuitable for covering large areas. However, with the ongoing expenses of... (read more)
2018-06-19 09:23:54

3D Sonar Technology

The journey from oil and gas to homeland security and back again
Since its introduction many years ago, survey sonar has evolved steadily, but is still a difficult and non-intuitive survey tool, requiring large amounts of processing to arrive at the most basic end product. Initially, anyone wanting to survey or inspect the underwater environment was limited to single beam echo-sounders, in simple terms one-dimensional sonar, yielding very little quantifiable data. These in turn were developed into mechanically scanned sonars, and subsequently into today’s high performance multi-beam and forward looking sonars which are the back-bone of the survey industry. Even the very best commercially available multi-beam sonar delivers only 2 dimensional data... (read more)
2008-01-01 01:00:00

Autonomous Vessel Delivers in Challenging Environment

Track Record Built During Shallow Water Survey
The hydrographic survey industry is changing and moving away from manned operations in an effort to reduce costs and increase safety. During the Shallow Water Survey 2015 conference this new approach and the associated challenges were assessed by Swath Services during the collection of ‘The Common Dataset’ associated with the conference. The aim of participating with an Unmanned Survey Vessel (USV) was to determine if it was actually possible to undertake such a high specification challenge with a USV. The common dataset provides a benchmark against which the performance of the USV can be measured. For 2015, The Common Dataset... (read more)
2016-07-26 12:01:22

Project SHOA, Waves in Chile

40-year wave climate model for the Chilean coastline
A detailed study of swell wave conditions in the southern Pacific Ocean has been performed, with particular emphasis on the western Southern American coastline. This study was one part of an overall wave hindcasting investigation undertaken for the Servicio Hidrografico y Oceanográfico de la Armada de Chile (SHOA) to define the inshore wave climate at various locations along the Chilean coastline. Chile is a long, relatively thin country that stretches along the western edge of the Southern American continent, as may be seen in Figure 1. It experiences large meteorological variability along this length. The climate varies from arid desert... (read more)
2008-01-01 01:00:00
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