Remembering The Battle Of The Atlantic: Dynamic Underwater Laser Scanning Of A WWII Battlefield
By: Kelci Martinsen, 2G Robotics Inc.
3D Model of German U-576. Photo credit: NOAA and 2G Robotics.
When thinking about the naval battles of the Second World War, the eastern coast of North America is not often the first battlefield to come to mind. However, crucial struggles over supplies were regularly taking place in the Atlantic. Sustained resources were critical to ensure an allied victory, without them, the allied forces in Europe would become increasingly ineffective, succumbing to a war of attrition.
One such conflict took place on 14 July 1942 approximately 35 miles offshore from Cape Hatteras, North Carolina. The German submarine, U-576, was returning home after sustaining damage to the main ballast tank from enemy depth charges. However, U-576 encountered convoy KS-520 consisting of 19 merchant vessels and five military escorts travelling from Norfolk, Virginia to Key West, Florida for an extremely vital resource—fuel.
ULS-500 PRO underwater laser scanner and submersible ready for deployment. Photo credit: NOAA and 2G Robotics.
The German submarine fired four torpedoes into the convoy, damaging a steam merchant and a tanker and sinking the freighter Bluefields. As the U-boat surfaced, Unicoi opened fire on the submarine, landing a successful blow. Meanwhile, Bluefields crew members quickly evacuated the steadily sinking ship. Minutes later, depth charges were released from two U.S. Navy aircraft, sending U-576 to its final resting place on the ocean bed. The entire submarine crew, consisting of 45 men, was lost and four allied crew members were badly injured.
Decades later, U-576 and Bluefields lay forgotten off the coast of North Carolina in approximately 800 feet of water—that is until the battlefield was rediscovered by NOAA. Due to the depth, NOAA was only able to document the sites via a Triton 1000/2 two-person submersible and so turned to a trusted collaborator, 2G Robotics, for an effective way to understand the newly identified battlefield. The submersible was equipped with Sonardyne’s SPRINT INS and 2G Robotics’ most advanced underwater laser scanner, the ULS-500 PRO, to dynamically capture true-scale 3D models of the sites. Even in adverse weather, NOAA’s team was able to complete multiple passes over the 65- and 80-meter baselines. The team diligently photographed U-576 and Bluefields as they passed over, capturing the magnitude of the battle’s carnage. The gaping void in Bluefields’ port side further emphasized the violence of the conflict. Meanwhile, raw laser point cloud data and navigational data were recorded and processed through EIVA navigational software, providing real-time display of data without the use of stitching. As the data for U-576 waterfalled in, it was plain to see the submarine had sustained little exterior damage and the hatches were still sealed tightly, giving additional insight into the last moments of the ill-fated crew members.
The data and 3D models captured by 2G’s ULS-500 PRO provided NOAA with a complete millimetric record of the artifacts and site integrity, allowing for precise measurements and improved analysis. NOAA will now be able to monitor site changes over time, particularly those transformations caused by human impact.
The project represents a significant step forward, not only for cultural resource management and in understanding the implications of WWII naval conflicts but also for public outreach. Maritime history is now more accessible, enabling anyone to experience 3D models of U-576 and Bluefields using a virtual reality system, further establishing underwater laser scanners as the new standard for underwater archaeological surveying.
3D model of Bluefields showing extensive damage. Photo credit: NOAA and 2G Robotics.
Blackfish: Three Decades In The Making Redefining Low-Cost Autonomous Underwater Vehicles
Lockheed Martin’s Marion, Massachusetts facility has been developing and building small A-size (4 7/8- in. Diameter, 36-in. Length) autonomous underwater vehicles (AUVs) for over 35 years. The A-size form factor has been and will continue to be extremely utilitarian, as it dramatically increases the number of potential deployment mechanisms available to the end-user beyond simple hand delivery. As the size is identical to standard sonobuoy devices, vehicles can be launched from standard sonobuoy launchers on board a wide array of fixed wing and rotary wing aircraft as well as submarines and surface vessels.
Expendable Mobile ASW Training Target.
Since the early 1980s, Lockheed Martin has been the primary supplier of Expendable Mobile Anti-Submarine Warfare (ASW) Training Targets (EMATTs) to over 20 nations, delivering over 40,000 systems to date for air-launch, surface-launch, and subsurface-launch applications. Understanding that the true value to the customer is in the quality of data acquired, the design of the EMATT has been optimized for training purposes, resulting in a vehicle that is inherently expendable and does not require the user to spend valuable time and resources executing recovery efforts. This optimization was enabled through initial efforts to drive unit price down through a combination of Design for Manufacturing (DFM) techniques and lean production flow.
To accomplish this, Lockheed Martin has implemented a manufacturing capability that provides our customers with the highest quality product at the lowest possible cost. We maintain a highly trained and flexible work force that allows Lockheed Martin to provide a diverse portfolio of products to our customers, maintaining flexible support systems that allow for product tailoring based on customer feedback and mission requirements.
Lockheed Martin has developed all of the production processes and tooling required to produce large numbers of A-size vehicles and is currently in full-rate production, producing vehicles for two dozen nations. These standardized processes include assembly, test, and inspection from material receipt to final product acceptance. As would be expected for any product suitable for military use, all processes and procedures are fully documented with well-defined step-by-step procedures to fabricate the vehicles in accordance with the engineering drawings, associated quality controls in place to define the process for inspection where required, and test instructions to define the necessary factory test process. All manufacturing documentation is controlled through a rigorous configuration management process that ensures consistent production of each individual vehicle. Through years of optimization and production flow modifications, the resulting production line is scalable with production throughput capability currently in excess of 2,500 vehicles per year.
Although Lockheed Martin has been building A-size AUVs continuously for over 35 years, we had been focused on a single mission, continuously refining the vehicle to reduce cost, but at the expense of mission flexibility and modularity. Several years ago, however, that approach was modified, taking into account the high volume production line, standardized manufacturing processes, and mature supply chain. The result was a new concept for a multi-purpose vehicle that leverages the lessons learned and experience gained from 40,000 fielded systems.
The idea of a multi-purpose underwater vehicle is certainly nothing new, especially with the proliferation of vehicle types over the past decade and the exponential increase in undersea mission requirements over that same period. Unfortunately, in most cases, the complexity and size of the required sensor packages has also resulted in AUVs becoming synonymous with being expensive or cost prohibitive. There must, therefore, be a place for a smaller platform that can accomplish a variety mission components at a fraction of the cost.
Production EMATTs and First BlackFish Prototype.
The BlackFish is Lockheed Martin’s latest iteration of a mission-reconfigurable vehicle based on generations of field-hardened products combined with state-of-the-art technologies. From concept inception, the BlackFish Design Team had several key underlying requirements from which they could not deviate:
• Vehicle must remain A-size, capable to being shipped and launched from standard Sonobuoy Launch Containers (SLCs);
• Vehicle must be suitable for air-launch, surface-launch, and subsurface-launch applications;
• Vehicle must be user reconfigurable; and
• Vehicle must be comparable in price to existing EMATT vehicles when configured for ASW training missions.
These four simple requirements ensured that throughout the systems engineering and design phases, key characteristics of the vehicle would be constant while other design attributes and capabilities would be variable, allowing for a wide range of innovative configurations while still staying true to the overall end goal.
Comprising two major sections, the BlackFish leverages capabilities from across Lockheed Martin, including the Missiles and Fire Control (MFC), Advanced Technology Labs (ATL), and C4ISR and Undersea Systems (C4USS) organizations.
The standard aft section of the vehicle includes three “pop-out” control fins, independently controlled by linear actuators; a ducted propulsion system; a multipurpose ceramic ring transducer paired with WHOI’s ìModem drive and processing electronics for acoustic communications; bathymetric sensors (temperature and sound velocity); base battery pack; guidance, navigation, and control suite; GPS receiver; and WiFi capability (Satellite Communications are available as an option). The navigation system leverages generations of proven low-cost navigators on Lockheed Martin missile programs and provides a flexible INS/GPS/ USBL/Terrain-aided navigation system with extensions to collaborative and relative navigation. Maintaining this array of sensors as a core set of components facilitates production flow efficiency while simultaneously reducing the resultant unit cost.
Mission execution capabilities are provided by an open architecture, extensible, MOOS-IvP-based autonomous controller with standard interfaces to the BlackFish lowlevel controllers. This flexible architecture allows for autonomy that is tailored to mission CONOPS, including the ability to override the base autonomous control with a payload-borne backseat driver operating over the same standard interface. An operator interface is provided for mission planning and mission monitoring, but plugins are available/planned for standard U.S. Navy user interfaces such as topside. Whereas the aft section of BlackFish is standardized and optimized for low cost, the forward payload section is reconfigurable by Lockheed Martin or the end user, utilizing a standard interface to the aft section for communication, data transfer, and power transfer. Various implementations of this section include side-scan sonar, thrusters for improved slow/zero speed maneuvers, additional battery modules for increased endurance, or any number of other sensors required for a given concept of operations.
Developed on the back of three decades of advanced development, low-cost production, and fielded test data, Lockheed Martin has extended the boundaries of the A-size vehicle. Whether the tasking centers on bathymetric surveys, infrastructure inspections, ASW training, or collaborative swarms of vehicles, BlackFish enables users to customize their product to fit their needs, increasing or decreasing inherent capabilities as required while utilizing a robust, quality-driven, costeffective product to complete their mission.
Micro-UUV Technology is Flexible and Fast In 2015, several veterans of the conventional Unmanned Undersea Vehicle (UUV) sector set out to change the dynamics of the industry, founding Riptide Autonomous Solutions. Riptide's first product was the micro-UUV, a new, highly flexible, open-source autonomous undersea vehicle that provides a state-of-the-art, low-cost solution ideally suited for developers of autonomy and behaviors, power systems, subsea sensors, and other new payloads. The micro-UUV features open hardware and software interfaces, giving users a reliable and robust platform to advance technology development. The vehicle design is optimized for high efficiency, with the best hydrodynamic signature in its class. The base micro-UUV is 4 . In. In diameter, 40 in. In length, and weighs 22 lb. The standard system is rated to a depth of 300 m.
A micro-UUV. The antenna is embedded in the fin for improved hydrodynamics.
Riptide's micro-UUV features three individually actuated control fins providing active roll stabilization. An active GPS antenna, WiFi communications, and vehicle recovery strobe LEDs are integrated into the vertical control fin, reducing the vehicle's hydrodynamic signature for maximum efficiency. Its open system design allows for easy user modification and customization, making this an ideal platform for a wide variety of development needs. Multiple energy source options allow maximum flexibility for endurance, safety, shipping, and mission optimization.
In contrast to typical proprietary architectures, the micro- UUV features a flexible software architecture leveraging a large amount of open-source software. The goal is to foster an active and vibrant user community who will be provided with source code under a standard opensource license. The micro-UUV architecture maximizes the use of existing open-source software, both to provide a mature platform and to tap into existing energetic user communities. In the initial release of micro-UUV software, Riptide is providing code for the Arduino and Beaglebone Black development platforms as well as support for the MOOS-IvP robot control engine. Future releases are planned to include support for ROS (the Robot Operating System) and streamlined user interfaces.
In addition to embracing current software development trends, the micro-UUV has been developed using a large quantity of 3D printing, which enabled affordable and quick evaluation of numerous design considerations. This rapid manufacturing capability has also enabled Riptide to quickly field production vehicles. This approach is not just for engineering the models—products capable of withstanding the pressures and harsh environment of UUV operations are also being produced this way. The use of modern design and manufacturing techniques has also enabled the development and delivery of numerous micro-UUV configurations. A variety of sensors, as well as wet and dry payload bays, have been rapidly developed and successfully delivered—and all within 15 months of the first conceptualization of the product.
Reducing Expense, Easing Logistics
This new generation of micro-UUVs has drawn on the successes and failures of earlier generations that were large, expensive, logistically cumbersome, and limited in endurance. Drawing on these experiences, UUV developers have evolved vehicle designs that optimize configuration flexibility and utilize rapid manufacturing capabilities to minimize the cost of the vehicle. In fact, given its entry price point of $10,000, the micro-UUV could, in certain applications, be considered expendable and abandoned after completion of the mission.
Earlier generation UUVs reflected the constraints of the requirements, technologies, and environment that fostered their creation. Costs were often based on the need to get the job done the best way possible. Once designed, manufactured, and sold, there was little incentive to reduce the costs. Consequently, a clean departure from earlier UUVs was required to make vehicles more conducive to low-cost manufacture and sale. It is this class of vehicle that has overcome the “expense” limitation and brought to market a step change in logistics that now makes new applications feasible.
Increasing Endurance
Full consideration of the drag/power/endurance relationship along with extensive hydrodynamic computer modeling can produce minimum hull drag and optimize fluid flow for extended endurance. In addition, the use of low-power electronic design permits optimization of propulsion and hotel power loads for minimum power consumption. What this means is that the micro-UUV can operate up to 48 hours at 2 knots on a battery comprised of AA alkaline cells. These endurance figures are quoted without a payload because endurance will be payload specific and endurance without payload provides a metric for direct comparison of vehicle capabilities. A sensor payload will reduce the overall endurance, depending on power requirements.
Batteries utilizing Lithium chemistry have improved endurance. Yet, even the capacity of these advanced chemistry batteries has provided limited improvements in the overall endurance of the UUV field while introducing safety and handling issues aboard ships prior to UUV launch.
Through the use of advanced power source technologies such as the aluminum seawater battery from Open Water Power, the Riptide micro-UUV has the capability to operate for over 500 hours at 2 knots (without payloads), enabling significant range and time on mission.
Riptide has an exclusive agreement with Open Water Power for use of their aluminum seawater battery in micro- UUVs and anticipates fielding the initial installation in late 2017.
Expanding the Family
Building upon the successful micro-UUV, two new vehicles have been developed. The new 1-Man and 2-Man Portable UUVs use the same technical architecture, proven hydrodynamic hull shape, and high-efficiency electronics as the original micro-UUV. Drawing upon advanced manufacturing, modern electronics, and open-source concepts, these larger vehicles will deliver the same flexible solution already favored by Micro-UUV users. The 1-Man Portable UUV offers a 7.5 in. (19 cm) diameter and base weight just over 60 lb (27 kg) with a depth rating of 300 m. The 2-Man Portable UUV has a 9.375 in. (24 cm) diameter and a base weight of roughly 120 lb (55 kg) with a depth rating of 600 m.
These new form factors will support new payloads and expanded mission possibilities. Introduced in April 2017, the expanded family of Riptide UUVs will enable new approaches to undersea operations.
A Big Future For Micro Technology And ecoSUB Robotics
Hand Launch of ecoSUB-ì. Photo credit: Planet Ocean Ltd and National Oceanography Centre.
As the data gatherers of the sea, autonomous underwater vehicles (AUV) are the go-to technology for those seeking knowledge from under the waves. Many vehicles are now able to travel vast distances across the world’s oceans, collecting valuable data for users in science, military, and commercial sectors. The technology has advanced substantially over the last decade as sensors become smaller, autonomy becomes smarter, and vehicles become more powerful, widening the net for more applications and opening doors to multi-use missions. And now, the latest trend in micro AUV platforms means this new cutting-edge technology and smarter systems will be more accessible than ever before. EcoSUB Robotics Limited is a brand-new company delivering advanced, low-cost micro AUVs. The innovative ecoSUB range will not only help provide access to superior data sets but could also lead the marine sector into a new age of advanced ocean knowledge.
The innovative system was born from an idea within the National Oceanography Centre (NOC) and nurtured in the head office of Planet Ocean Limited, a UK-based marine science technology specialist. After extensive collaboration with the UK’s Marine Autonomous Robotics Systems (MARS) group at NOC, the ecoSUB micro AUV range was launched.
Terry Sloane, CEO of Planet Ocean Ltd and ecoSUB Robotics Ltd, is confident that these low-cost platforms will help many more users across research, academia, and teaching access marine autonomous systems (MAS) and apply the benefits of collecting wide spatial and temporal data. “We wanted to create a capable vehicle that would draw upon the latest sensor, energy, and materials technology to democratise the use of AUVs. It was important to us that the system was easy to use, performed worthwhile missions without compromise of specifications, and, above all, it had to be affordable.”
The ecoSUB programme officially began in 2015 after a successful Planet Ocean bid won funding by Innovate UK and DSTL. The project aimed to develop the launch and recovery of multiple AUVs from an Unmanned Surface Vessel (USV). In turn, this stimulated the development of the micro AUVs based on an original NOC concept vehicle.
By November 2016, the micro AUV platform was finally revealed and launched as “ecoSUB-ì” at the NOC MARS Innovation Showcase. Early in the project, BP showed significant interest and funded the parallel development of a second AUV—a vehicle that can dive deeper with a larger payload capability. The 8-month project resulted in the slightly larger, but still one-man deployable “ecoSUB-m,” which was also uncovered at the MARS Showcase event last year.
Sloane said, “Micro AUVs have several benefits that stand out over larger AUVs. Cost is an important one, which by default leads to several others. The small size means that manufacturing costs can be less, but perhaps more importantly, the cost of ownership is less. There are no expensive mechanical handling systems required to support launch and recovery, and they can be transported cheaply. Furthermore, maintenance and support costs are lower, and there is less time needed for training and familiarisation compared to larger systems.”
The benefit of a low-cost system means that several vehicles can be deployed on a single mission to produce far higher temporal and spatial data sets than would be obtained with a single, more expensive AUV or glider. While the small size means that users are not yet able to carry large suites of sensors on a single vehicle, users can equip multiple vehicles with different sensor combinations to achieve the same results.
“The future for ecoSUB is very exciting.”– Terry Sloane, CEO of Planet Ocean Ltd
“Because the vehicles are small, we have had to work smarter to achieve meaningful mission capability in the absence of expensive components such as DVLs or USBL positioning systems. The small size means that the ì version is capable of being air launched from small, fixed-wing autonomous aircraft (UAV) or indeed multi-rotor platforms. The University of Southampton are actively engaged in a programme to demonstrate this.”
The ongoing programme is a collaboration with Planet Ocean Ltd, NOC, ASV Ltd, and the University of Southampton. ASV Ltd have developed an automated launch and recovery system, while a team of engineers from Planet Ocean and the NOC MARS group worked together to build a micro AUV platform capable of serving a broad range of sectors. The resulting systems have the capability to deploy advanced sensors such as high accuracy CTDs, dissolved oxygen, and fluorometers.
“Our academic partner, the University of Southampton, have provided their new wave tank for initial response testing. Of course, being located in the NOC innovation centre has also allowed us to benefit from the considerable test facilities located there—we have been testing and developing behaviours and refining control systems in closed, freshwater facilities that allow us to undertake these tests in controlled conditions,” explained Sloane.
During the ecoSUB programme, engineers have had to overcome several challenges, including lack of available high-performance sensors compatible with the needs of a micro platform. Power supply chemistry was also a critical issue so that they can achieve the desired speed and endurance as was incorporating the required intelligence to achieve high levels of autonomy in such a small body. Use of advanced 3D printing technology has accelerated the design process and allowed the teams to evaluate several solutions quickly and economically.
Now, ecoSUB is currently entering the open-water test phase where the vehicles and sensors will be put through their paces in real mission scenarios.
Introducing Micro Platforms to the Industry
Around the world, there are a huge number of potential users of AUV technology in the areas of science, defence, oil and gas, and commercial sectors. But, not everyone could access the technology. The ability to afford or even to evaluate AUVs as a useful addition created an obstacle that, until now, prevented many users from incorporating the technology within their work.
“We engaged with potential end users in the first year of the project and their input, encouragement, and backing has been extremely useful—it has helped shape the project. Since the launch, feedback has been exceptional. We have received orders for five advanced prototypes and additional funding to supplement the Innovate UK investment. There is also considerable interest from collaborators in future R&D activity to expand the capabilities of the vehicles. So, already we can say that the future for ecoSUB is very exciting,” said Sloane.
There are several key applications ecoSUB Robotics envisages for the new micro AUV range. Whilst micro AUVs are not seen as replacements for the larger, more capable platforms, it is likely these systems will be able to complete missions that a traditional AUV or glider cannot. And, because of size and cost, there will be new options in terms of how missions are structured using “shoals” of vehicles instead of just one or two large platforms.
Testing of ecoSUB-ì in University of Southampton wave tank facility. Photo credit: University of Southampton.
Sloane said, “Of course, we have had a lot of applications suggested to us by potential users, some of which we had considered, but many which we had not. This provides us with a healthy development path going forward—the challenge is deciding which to tackle first. Many like-minded groups are operating in the UK and elsewhere that are developing technology which will enhance the capabilities of ecoSUB in the coming months and years. We find this very exciting, if not a little challenging.”
The defence sector already recognises the potential for autonomous system use in their situational awareness and tactical operations. EcoSUB hopes to dramatically reduce barriers to MAS use in this sector by significantly diminishing logistical challenges of launch, recovery, and operations. There is also scope for integrated mission control and useful, focused data products to deliver key information when and where it is needed.
Dr Alex Phillips, lead designer, with ecoSUB-ì against some of the NOC Glider fleet. Photo credit: Planet Ocean Ltd and National Oceanography Centre.
“All of the team believe in great design and challenging the status quo.”– Terry Sloane, CEO of Planet Ocean Ltd
Commercial operators, especially in the oil and gas sector, see enormous potential in the affordable use of MAS for a whole range of activity, including a rapid environmental assessment, subsea inspection, and asset monitoring and support.
Most importantly, the initial low-cost investment will also help users test the system capabilities in a variety of conditions and scenarios without the financial burden and risks associated with the larger alternatives. This will not only help to build the trust required in the technology before use in live missions, but also gives rise to new opportunities to use these systems in applications where AUV use was not possible, or even considered, until now.
A Big Future for Micro AUVs
As technology in this sector continues to advance at an astonishing rate, the industry will likely see smaller, lower power, and more accurate sensors arriving. This will not only improve what micro AUV platforms can offer, but enable users to measure more parameters in the future. And, so that more complex missions can be undertaken, vehicle-to-vehicle and vehicle-to-surface communications should develop quickly along with improvements in navigation.
“In the next 5 years, we will see much more integration of micro-AUVs with larger AUVs, ASVs, and UUVs in everyday data-gathering activities and hopefully advances in energy technology—given the levels of investment being put into this area currently. At the moment, satellite communication bandwidth can be a limiting factor in some instances so there needs to be some improvement in this area if the technology is going to advance any further,” commented Sloane.
“It is great to see a few new players in this emerging sector, each taking slightly different approaches, but, overall, this validates our thinking. This process has been challenging, but also exciting, fast, slow, thought provoking, and creative. All of the team believe in great design and challenging the status quo. ‘Disruptive technology’ is an overused term, but not in this context! But, what can the industry expect to see for ecoSUB in the coming years? I’m not saying just yet.”
Acknowledgements
Terry Sloane, CEO of Planet Ocean Ltd and ecoSUB Robotics Ltd, UK.
More than 30 years ago, Tecnadyne delivered its first thrusters to Mitsui Engineering and Shipbuilding in Tokyo. Since then, the company has manufactured and delivered over 8,000 thrusters. The primary focus of the company has been underwater propulsion, motion control, and related technologies for remotely operated vehicles (ROV). Headquartered in San Diego, California, Tecnadyne’s manufacturing facility is involved in design, fabrication, assembly, and development of customized subsea systems. The company more recently has increased its focus to include propulsion systems for for AUVs. ON&T talked with founder and president o f Tecnadyne, Andrew Bazeley.
ON&T: Could you give us some background on your AUV propulsion systems?
Bazeley: We have a fairly new application, which is building thrusters for AUVs. When I started the company 34 years ago, we were building thrusters for just ROVs. The thruster for an ROV is more of a general thing. You’re just concerned with how much push you can get out of that thruster—you really want the most bang for your buck. When you make a thruster for an ROV, it’s a more compact thing, it produces a lot of thrust but isn’t very efficient.
ON&T: Now you are designing thrusters for AUVs. How is that different?
Bazeley: Every single AUV is different in its requirements for the propulsion, and it is different in how they move through the water at a forward speed or velocity. Sometimes they move quite fast. They need a thruster or propulsion system that allows them to move through the water at the speed that they need to move. They also need to do so as efficiently as possible. It has to be efficient because, in almost all cases, a battery powers AUVs. In order to stay underwater to complete a mission, you are juggling the amount of power in the battery and the power of the thruster.
ON&T: So, you are dealing with a much different case in AUV thruster design.
Bazeley: Yes, a special or purpose analyzed and design thruster needs to be built for each AUV. We have to look at how much power that AUV can deliver, but we need to look at what speed it needs to move through the water and how much thrust it’s going to take to move that AUV through the water at that speed. We have developed some very good analytical tools to model appropriate propulsion. We can play with a lot of propeller characteristics. This isn’t something that is totally new and unique because modeling propellers for optimum efficiency has been going on in the shipping industry and the ship building industry since the beginning of propeller-driven cargo ships. In their case, they are crossing big oceans and want to do it as efficiently as possible. It is not that they have limited power on the ship, but they want to use as little as they can and as cheaply as they can to maximize their profits. The difference is that an AUV operates submerged, while surface cargo ships have to take into consideration the air/water interface.
We have developed some very good analytical tools that not only allow us to optimize the propeller design, but also optimize the propeller design working in concert with an electric motor and, in most cases, a gear box to reduce the speed from the electric motor for a proper speed for the propeller. We are now able to very accurately model the entire propulsion system for an AUV. We can analyze, design, manufacture, and deliver an AUV propulsion system that meets the performance and mission requirements of that particular AUV.
ON&T: Could you talk a little more about the tools used in your process?
Bazeley: The analytical tools we have are all software. The design of the thruster uses fairly well established hydrodynamic principles. The data have changed over time, but knowing how to use those data, information, and know how is another matter. Especially when applied to the AUV case, which is a little bit different from the established applications. We also have the ability to model the electric motor and gearbox with the propeller and are able to treat that entire propulsion system as a single black box. The client puts in power on one side, and we deliver propulsion or thrust on the output.
DC Brushless Thruster Model 560.
In addition to those analytical tools that we have which are all software based, we have pretty sophisticated testing abilities. We are able to test the performance of these propulsion systems and thrusters that we build. We are able to do that in a pretty timely and cost effective way. Part of the reason we are able to do that is because we rely on many of the building blocks we have designed over the 34 years that we built thrusters for ROVs. We are able to choose from a dozen motor frame sizes that we already have comprehensive performance data on and that we have in stock. We are also able to select from maybe 18 or 20 gearbox configurations that we have already built and tested and generated the performance data. We have the ability to take these different components off the shelf, and that is what we do when we are doing the analytical work. We are just using those building blocks that we have and have developed over 34 years. We have them all on the shelf.
ON&T: So, you are creating new designs for AUV applications built on time-tested components.
Bazeley: Yes, we are able to marry that to new propeller designs so that we can do rapid prototyping. Depending on the size and complexity of the propeller we will, at least at the prototype level, print the propeller in 3D or an investment cast of the propeller out of stainless steel.
ON&T: You’re also providing the client with a one stop- shop experience.
Bazeley: Because of our experience and vast array of building blocks, we are able to build the entire propulsion system in one black box assembly. It is not a matter of a customer going to a company to design a propeller for them and then going to another company for the motor and then another company to bring the two together and then realizing for one reason or another the performance doesn’t meet the needs for the propeller. That happens a lot, believe it or not. We are able to conceptualize, design, develop, and manufacture these propulsion systems and get them in the customers hands in a relatively finite and reasonable amount of time with a pretty high degree of confidence that the performance they see when they get that thruster is the performance they were anticipating.
Kongsberg Maritime’s Marine Robotics (MARO) team is the driving force behind the most extensive portfolio of autonomous underwater vehicle (AUV) technology in the world. The company’s HUGIN AUVs have forged a path for the acceptance of this advanced technology as a viable, optimal survey and inspection platform since 1993, while the MUNIN AUV offers the same advantages, but in a more compact platform.
HUGIN is KONGSBERG’s original AUV and through constant development is still recognised as a state-ofthe- art, highly reliable and effective platform. Combining IHO-quality positioning with low noise and the highest resolution survey sensors available, HUGIN is the most complete platform for seabed mapping, pipeline inspection, and mine countermeasures. Capable of operating at depths to 6,000 m with mission durations of more than 75 hours, HUGIN’s size and flexible configuration options enable it to collect data from diverse sensors, resulting in a complete data set from a single mission.
HUGIN can operate at depths to 6,000 m for over 75 hours at a time.
Launched in 2013, MUNIN is capable of missions of up to 24 hours in water as deep as 1,500 m. Measuring between 3 and 4 m in length with a 34-cm diameter, the 600-m rated MUNIN weighs less than 300 kg, making it one of the most compact and yet highly capable commercial AUVs available today. It features a modular construction, enabling operators to mobilize the system quickly without the need for calibration. It is also compatible with KONGSBERG’s pipe tracking software, using the sidescan sonar to autonomously track alongside a pipe.
While HUGIN, MUNIN, and Kongsberg Hydroid’s Remus AUVs continue to be the first choice in the offshore, research, and naval sectors, the MARO team has diversified KONGSBERG’s AUV offering in recent years, most notably through the Kongsberg Seaglider platform and a collaboration with NTNU and Statoil to develop the unique Eelume solution.
Seaglider is an autonomous underwater glider developed for continuous, long-term measurement of oceanographic parameters. Rather than an electrically driven propeller, the vehicle uses small changes in buoyancy and wings to achieve forward motion. The system’s pitch and roll are controlled by moving the battery mass inside the vehicle.
Eelume features a flexible, modular design that introduces new possibilities underwater.
Eelume is a radical re-imagining of the accepted AUV standards. Featuring a ground-breaking, futuristic design based on a unique flexible and adaptable body, Eelume is designed to live permanently underwater and carry out underwater inspection and intervention tasks that would normally require the mobilisation of expensive ships for divers or the launch and retrieval of other ROVs.
In addition to its superior manoeuvrability, Eelume is a highly stable sensor and actuator platform offering unmatched access to confined areas inside subsea structures enabling diverse operations. The Eelume solution will dramatically reduce costs and the environmental impact associated with having a ship overhead as is normal for traditional underwater intervention operations. It can be installed on both existing and new fields where typical jobs include visual inspection, cleaning, and operating valves and chokes. These tasks account for a large part of the total subsea inspection and intervention spend.
Eelume represents a radical diversion from the standard approach to developing AUVs, ROVs, and other marine robots. It will deliver significant new capabilities when it becomes commercially available in 2018. While Eelume brings a new approach, as a leading AUV developer Kongsberg Maritime continues to offer the largest, most advanced portfolio of tried and tested AUV platforms for all applications.
For over 20 years, U.S. Underwater Services, LLC has provided commercial diving, inspection, repair, and maintenance services to industry sectors such as oil and gas, shipping, municipal works, power generation, construction, engineering, defense, and marine infrastructure.
From its 50,000 sq. ft facility in Mansfield, Texas, U.S. Underwater Services manages all of its business operations, sales, equipment maintenance, and product fabrication. The facility also boasts a 22,500 gallon multi-level training tank that is used for certifying underwater welders, ROV and non-destructive testing training operations, underwater videography techniques, equipment and product testing, emergency drills, and demonstrations. This training tank has also been utilized by other companies for the purposes of R&D, product demonstration, and to familiarize company representatives on safe diving techniques. Visitors and client representatives have the opportunity to view these activities from several vantage points—via large portholes, live feed video, or from the surface.
Safety First
Since 1996, U.S. Underwater Services has been an active member of the Association of Diving Contractors International (ADCI), a professional association that promotes best industry practice with respect to the health and safety of commercial divers and underwater operations worldwide.
Additionally, the company is involved in several industry groups that focus on diver safety and training. One example is the U.S. GoM Diving Safety Workgroup, a non-competitive and non-commercial group of oil and gas operators, transmission companies, commercial diving companies, and industry stake holders that promote safe diving practices in the Gulf of Mexico.
U. S. Underwater Services has been audited by several major oil and gas operators as well as drilling contractors, power generation companies, and government entities to ensure that their operations meet the industry’s most stringent safety standards.
Experience Matters
For over 15 years, U.S. Underwater Services has been the leader in MODU inspection, repair, and maintenance services in the Gulf of Mexico.
However, some of the other services that they provide include certified underwater welding; platform and pipeline inspection and repair; site surveys; site clearance and debris removal; NDT services; vessel husbandry; diver- supported dredging; and the refurbishment of coastal structures such as docks, piles, and piers.
The company continually invests in its equipment, training, and facilities in order to expand its capabilities and maintain its reputation as a leading and trusted provider of commercial diving services, both inland and offshore. Combining state-of-the-art equipment and extensive industry experience, U.S. Underwater Services has the capability to complete projects of any scale.
The Skill To Survive: Survival Systems USA Provides The Ultimate High-Tech Training To Prepare For Real-World Dangers
By:Rhonda Moniz
Survival Systems USA, Inc. is an employee owned company in Groton, Connecticut dedicated to safety and survival education. The family of companies was established in the1980s in Dartmouth, Nova Scotia after Canadian pilot and founder Albert Bohemier survived a plane crash.He credited his survival to the training he received while in the military.
Passive Acoustic Monitoring By USV: Wave-Propelled AutoNaut Comes Of Age
By: Phil Johnston, AutoNaut Ltd.
Recent years have seen an explosion in the number of applications for unmanned surface vessels (USVs), including a game-changing solution for Passive Acoustic Monitoring (PAM) detection of whales or submarines, the AutoNaut.
Low noise, high mobility, and long mission duration are key requirements for acoustic surveys. These are areas where AutoNaut is particularly capable, enabling the measurement of underwater sound and monitoring of marine mammals, which are two tasks in high demand from both the commercial and academic sectors. For defence purposes, the same capabilities mean proficiency in listening for submarines.
