Digital Twins

Individual shipowners may not always have the resources to invest in their own research and development. With intense competitive pressures, rising bunker prices and new compliance costs, their focus is on the bottom line. 

But R&D comes naturally to class societies, which have engineering expertise at the core of their business model and are leading the way in developing new data-driven opportunities for shipping. While the top class societies' much-discussed “digitalization” initiatives may sound futuristic or abstract, they are all driven by a classic value proposition: using technology to reduce cost and improve efficiency.

Condition-Based Class

Using shipboard sensor data on vibration, pressure, temperature and other factors, vessel operators now have the option of moving to condition-based rather than calendar-based maintenance for their machinery. The American Bureau of Shipping is currently working with the U.S. Navy's Military Sealift Command (MSC) to take this development one step further. Using new hull-mounted sensors and other data, ABS hopes to pioneer a "condition-based class model" – not just condition-based maintenance, but condition-based surveying, classification and rulemaking.

ABS has already created condition-based rules for equipment inspections with timetables informed in part by the operator's own preventive maintenance plan. DNV GL has made similar advances, notably a data-driven schedule for removing tail shafts for inspection. However, ABS's project with MSC might be the first attempt ever made toward developing a classification program that uses data to drive surveys instead of a date on a calendar.

Working with MSC, ABS is using detailed survey assessments to create "digital twins" for three different vessels. For each ship, ABS will use data from maintenance records, surveys and hull-mounted sensors to update the virtual model, creating a continuous digital database of the ship's condition. The underlying requirement is the availability of high-quality information from all available sources including the sensor network, the shipowner, the class society and third-party vendors.

According to Howard Fireman, ABS's Chief Digital Officer, this data "partnership" offers multiple benefits. The most important is condition-based maintenance – using data to make better maintenance decisions. With advanced analytics, shipowners can better predict when their equipment will need repair, thereby reducing costs, avoiding unplanned downtime and improving safety. If an owner can avoid $2 million in engine repairs by installing $500,000 in sensors, the business case for the system is already made.

A second benefit, condition-based inspection, will allow ABS surveyors to direct their attention to areas that the "digital twin" data model highlights. If the sensor data shows questionable values for a particular piece of equipment, the surveyor may spend more time examining that element.

A third major benefit pertains to ABS's fleet as a whole, not just the individual shipowner. "Our portfolio includes more than 12,000 assets, and the lessons we learn and trends we identify as a result of this partnership will enable us to update our rules for the benefit of not only our fleet but the industry as a whole,” says Fireman.

A fourth benefit, contingent upon regulatory approval, would be a fully condition-based survey program, potentially including condition-driven drydocking dates. For now this is in the conceptual stage since it would require change at the IMO level. 

"We're in a time of early transition between the calendar-based class model and the condition-based model," Fireman says. "Look at the aviation industry and the amount of data that's captured from every flight. If you look back at their progress over the past 30 years, you'd say 'Wow, these guys are all over it.' And we’re just beginning our journey."

3D Maintenance 

Bureau Veritas is also investing in data-driven, condition-based maintenance, particularly in software and the use of data for predictive purposes. The BV Veristar AIM3D platform integrates a digital model of the vessel with a lifelong database of inspection results, equipment data, modifications, classification requirements and other key factors, giving the operator a visual representation of an asset's status.

AIM3D is based on the 3DExperience platform, a collaborative design, analysis and simulation suite developed by French aerospace company Dassault Systèmes. Before steel is cut, naval architects, yards, class and owners can use the AIM3D platform to communicate about a new vessel's design, using a common visual representation of the ship. 

This model-based process saves considerable time for BV engineers during the design review phase and can streamline work for shipyards as well – not just as a way to accelerate the process of perfecting a design but also as a way to visualize how the ship will be built, block by block. China’s Jiangnan Shipyard uses this AIM3D feature to foresee and avoid problems during construction.

When the vessel enters service, the existing records in AIM3D can be continuously updated as a digital twin, allowing the operator to assess an asset's condition and predict when maintenance will be required. Accessing data on a piece of equipment is as simple as zooming in to the virtual "location" of the object and selecting it. 

Maintenance managers can then flag areas of interest for inspection. Malaysian offshore operator MISC Berhad is deploying AIM3D for the FPSO MaMPU 1, FPSO Cendor and the newly-converted FSO Benchamas 2 to monitor conditions, plan maintenance and share a common picture with contractors on board.

New Rulemaking Initiative

Like its peers, DNV GL is investing in digital opportunities, but it’s also leading a global rulemaking effort to open the industry to new technology. DNV GL Maritime CEO Knut Ørbeck-Nilssen is the current head of the International Association of Class Societies (IACS), which sets unified requirements for its 12 industry-leading members, and he has put digitalization at the top of its priority list this year. 

This entails leading an effort to review IACS' existing requirements and identify barriers to increased vessel autonomy. It also means facilitating the use of modern inspection technologies like drone surveys and remote inspections. "The surveyor has always gone to the item of interest [on board] to look at it,” Ørbeck-Nilssen says. “Now we can bring the item of interest to the surveyor using drones, cameras and other modern technology." 

Internally, DNV GL is working on a wide variety of digitalization initiatives ranging from e-certificates to “smart algorithms” for routing inquiries. It’s also launched a new cloud-based data storage, data sharing and analytics marketplace for shipping, which it calls Veracity. With Veracity, DNV GL Group CEO Remi Eriksen says his firm is "not looking to own data" but rather to serve as an independent adviser, just as it always has as a provider of classification services.

Proprietary data has real value to maritime companies, and DNV puts trust and security at the center of Veracity's design. "The data that we have available, that's our gold, that's what we have to use in the future to [make] the right decisions," says Rolf Thore Roppestad, CEO of marine insurer Gard, which has partnered with DNV GL to put its data to use. 

Vessel Autonomy

Many class societies welcome the potential of vessel autonomy, but Lloyd's Register is one of the few to work directly on the technology itself. In 2016, researchers from LR partnered with Queen's University Belfast, Atlas Elektronik, Warsash Maritime Academy and Rolls-Royce to develop an advanced autonomous navigation software system.

The “Machine Executable Collision Regulations for Marine Autonomous Systems," or MAXCMAS, is a collision-avoidance system that pulls together data from a range of shipboard sensors and uses it to safely navigate the vessel. Like Leidos' ACTUV project for the U.S. Navy, MAXCMAS is intended to maximize compliance with COLREGs and conventional practices of good seamanship.

MAXCMAS is intended to handle meeting, crossing and overtaking situations, but its algorithms are also written to navigate more complex encounters including targets that fail to comply with COLREGs, crossings involving more than two vessels and situations involving multiple COLREGs rules. If necessary, MAXCMAS defaults to Rule 2 and takes all necessary action to avoid a collision. 

Rolls-Royce reports that simulation testing has proved the system's worth. “Through MAXCMAS, we have demonstrated autonomous collision avoidance that is indistinguishable from good seafarer behavior," claims Rolls-Royce engineer Eshan Rajabally, who led the project. His team used Warsash Academy's full mission bridge simulators to test MAXCMAS, applying the same evaluations normally given to human mariners. Rajabally says the system received high marks.

MAXCMAS will continue its testing in the real world. In April, the Royal Navy took delivery of Atlas Elektronik's prototype autonomous minesweeper, RNMB Hussar, which uses the same MAXCMAS algorithms to navigate. Hussar is now undergoing further trials at the British Underwater Test and Evaluation Centre in Scotland. Pending successful results, the Royal Navy will begin testing its mine-hunting mission package next year. – MarEx 

Paul Benecki is the magazine’s Americas/Europe Editor.