3D Laser Scanning: An Innovative Aid for Marine Applications--Repair, Retrofit, Replace, Refurbish, Renovate, Repurpose, Restore

Today’s marine technologies encompass work in the fields of transportation, merchant markets, and the military, as well as underwater exploration, offshore drilling platforms, and high-speed and pleasure crafts.  Under their umbrella are the most complex mobile structures in the world, and millions of people’s lives and livelihoods depend on them.

Against this vast canvas exists a common problem: many marine vessels and offshore platforms in service today do not have digital documentation or CAD models, so when they are due for any kind of repair work, updating, or refurbishing, the process is hit-or-miss as to whether new parts will fit and function correctly.  The inherent inaccuracy of the physical vessel’s dimensions when compared to its existing 2D plans means that there are always mismatches between design data and reality.  The actual as-built shape of the vessel, from the hull to the layout of internal features such as piping, does not accurately reflect design prints.  Long-range laser scanning’s true-to-life modeling results offer naval architects and marine engineers spot-on data of their vessels and platforms to ensure that they are updated correctly and safely the first time, saving both time and money. 

GKS Global Services, an international provider of scanning services since 1981, has pioneered laser scanning and other techniques for overcoming the issue of the as-built structures not conforming to their design prints in the aircraft industry, and these techniques are now common practice in that industry.  In the last decade, laser scanners have acquired the range and accuracy to capture marine-sized structures to an accuracy equal to their manufacturing tolerances.  Software applications that develop 3D models of plans such as piping and valves by recognizing the components that make up the system now exist to cut down the scanning and modeling time dramatically.  GKS has expanded its area of scanning proficiency to include the marine industry through GKS Marine Services. 

The breadth of expertise and responsibilities involved in naval architecture and marine engineering fields includes design, construction, and installation of the systems related to marine structures and vehicles as well as their operation, repair, maintenance, and support.  3D laser scanning provides modern marine professionals an extremely versatile tool for precisely documenting structures, electronics, engines and turbines, navigation systems, electrical systems, hull fluid dynamics, and even nuclear systems elements. 

What is long-range 3D scanning?

Long-range scanning for marine applications is a ground-based technique for collecting high-density 3D data to create digital models of complex entities such as hull models, entire seagoing vessels, shipyards, engine rooms, ships’ systems, and other big structures and locations, both inside and out. Using the highly accurate 3D scan data generated with long-range laser scanning, engineers and designers can create CAD models of actual site conditions by processing the scan data into universally usable CAD models.

GKS Marine Services has performed many long-range marine scanning projects, from reverse engineering ship hulls to documenting engine rooms and calculating volumes of fuel tanks and is able to perform on-site 3D scanning of objects that are virtually unlimited in size since the size of the specimen being scanned is no longer limited to the directional travel of a machine, or the reach of an arm.  The laser scanning unit records all objects within the range and sight of the scanner. Long-range scanning functions in virtually any environment including broad daylight, the dark of night, indoors, and outdoors. 

Since grayscale values are applied to the X, Y, and Z coordinates, the data has the appearance of a black and white photograph. Scans can also be done in color, where each measured X,Y,Z coordinate is assigned an RGB color value. The specialized scanning software used offers a variety of additional options such as overlaying digital images on the top of the point cloud for enhanced realism.  Special software applications are also available to develop 3D models of plans such as piping and valves by recognizing the components that make up the systems.  Laser scanning technology is timesaving, clocking in at 100 times faster than conventional scanners, collecting 8 megapixels of data in less than one minute, so even the largest scan scenario is time-efficient. Non-contact laser scanning means that no detail is omitted or disturbed.

Retrofit, refurbish, replace, repair, and upgrade equipment and systems

With the constant strains imposed on vessels and ocean platforms by the forces of water, keeping things in “ship shape” is imperative to seaworthiness and safety.  A major factor that prevents implementation of design upgrades is a lack of as-built dimensional data. Continuous upgrades, repairs, and replacement of many systems can be efficiently accomplished when up-to-date CAD data of the systems’ configurations exist. 

Long-range laser scanning accurately and efficiently scans an entire system or room, such as an engine room, to document geometry, placement, and space constraints. Scanning can aid in the upkeep and improvements to:  

Special software applications are available to develop 3D models of plans such as piping, wiring, and valves by recognizing the components that make up the systems.  These advanced software packages greatly expedite the scanning and modeling process. 

If a ship is out at sea when a repair is needed, having accurate system data to share can help a shore-based engineer in advising sailors how to best go about fixing the problem. 

Repurpose marine vessels

3D scan data of a vessel’s hull or platform structure can also be used for marine simulations and testing.  Laser scanning provides the high resolution data very quickly, so digital models can be made and used to create 3D virtual spaces and simulations on an in-service vessel.  

If a vessel is to be repurposed, for example a cargo carrier converting to a passenger ship, simulations can be run with the scan data CAD model to test the stability, which of course, is a critical factor. Simulations provide data on how a vessel will behave in rough seas and about its maneuverability. Being able to do testing on the precise 3D measurements saves time, and craft safety can be certified without lengthy dry-docking. Alternately, design modifications can be made and the CAD model re-tested if the as-built craft is not suited to the new function.

In addition, analytical software for Computational Fluid Dynamics (CFD) can take the scan data gathered by GKS and use mathematical formulas to study and analyze water flow problems, leading to improved hull and structure architecture, fuel efficiency, power transfer, craft stability, and safety. 

Restore a vintage or damaged boat

As noted previously, many vessels are not documented with 3D CAD models, which is a major roadblock to performing any major restoration on a vintage or damaged boat.  With the increased availability of long-range laser scanning from reputable service companies like GKS Marine however, this lack of 3D data can be easily remedied. 

GKS has laser scanned many vintage boats, both seaworthy and damaged, for collectors who wanted to restore their prized possessions to mint condition.  The free-form, complex shape of the hulls is difficult if not impossible to recreate by any other method because of the irregular geometry and small details. Of course, non-contact laser scanning does not damage the article being scanned, so the boat is not be harmed in the scanning process and all the intricate design work is captured. 

With laser scanning, the as-built, 3D digital data is collected quickly and accurately.  Once the entire surface geometries of the exterior and the interior are captured, the pre-processed raw data contains millions of data points which adequately define the boat for reverse engineering. Without non-contact 3D laser scanning, capturing enough data coordinates to accurately define the boat’s shapes would take at least 10 times longer, and would result in a much less complete data set. 

After GKS scans the vessel, the scanning software automatically connects the point cloud data from multiple views into a common coordinate system in a single scan file.  The modelers then create a CAD model of the boat “as-is” for exact replication, or if modifications or repairs are needed, the original design intent of the prismatic shapes can be extracted even if the as-built part is warped, misaligned, or broken.  A boat designer can make the desired modifications or digital “repairs” in the CAD model to faithfully replicate the original or incorporate updates. 

The future of 3D laser scanning in marine applications

The ubiquitous problem of nonexistent CAD models of marine vessels and offshore platforms is a significant lapse which affects not only the ability to repair, retrofit, remodel, and repurpose marine structures, but also has serious safety ramifications for marine workers and passengers alike. The fact that extant 2D plans are inaccurate when compared to the 3D reality is also a concern.  Long-range laser scanning is an innovative aid to naval architects and marine engineers in their wide-reaching work of redesigning, repairing, repurposing, and restoring marine vessels, structures, and systems to be up-to-date, safe, and structurally sound.  Experienced service providers such as GKS Marine Services are a boon to the field, providing accurate CAD models to increase confidence and safety while saving time and money.

Stay tuned for the next Marine application story...
 

About GKS

GKS Marine Services, a part of GKS Global Services, has been a leading provider of 3D laser scanning, dimensional inspection, long-range scanning, and CT scanning services for over 25 years, with specialized experience in marine applications.  Also GKS now offers development and design services, rapid prototyping, complete contract manufacturing services, and equipment rentals.

For more information, request an online quote.