Case Study: CAD/CAM for Naval Refit

 

The ANZAC Class is a ship class of 10 frigates: eight operated by the Royal Australian Navy and two operated by the Royal New Zealand Navy (RNZN). They have an overall length of 118 meters and a displacement of around 3,800 tons.

 

In 2014, New Zealand ordered extensive modernizations to its frigates’ core combat and related systems. This would require the integration of the Lockheed Martin CMS 330, integrated with radar improvements, MBDA’s independently-guided Sea Ceptor missiles and an extensive array of other modern equipment.

 

As part of this project, naval designer thyssenkrupp Marine Systems Australia Pty Ltd. (tkMSA) was contracted to provide the overall ship designer function across the wide ranging upper deck and internal impacts. These impacts included the design of two mast modules.

 

tkMSA needed a CAD/CAM software solution to coordinate work in all engineering disciplines, be able to seamlessly handle both 2D and 3D input and output, and a way to easily communicate with the various stakeholders.  The company therefore chose to expand its suite of ShipConstructor and Autodesk software products to complete this upgrade job.

 

As a starting point for the new designs, the company had raster drawings and AutoCAD 2D drawings of the existing ship. It used the raster drawings as an underlay then utilized Autodesk Raster Design to convert the raster images into vectors and then clean up the drawings.

 

During the process, tkMS used laser scanning as a way to capture ship configuration, to check the measurements and to pick up any discrepancies from what the original drawings showed.

 

Since the starting point for the new design was now a set of 2D AutoCAD drawings, it was easier to begin 3D design in ShipConstructor. SSI’s ShipConstructor is based on an AutoCAD foundation and is seamlessly integrated into the Autodesk platform. The fact that there was a smooth transition from 2D to 3D, and then later, from 3D back to 2D, is an advantage empowered by the unified Autodesk environment and the underlying sophistication of the ShipConstructor/Autodesk technology, according to SSI.

 

During the design of the masts themselves, tkMSA used ShipConstructor for all facets of engineering, from structure to outfitting. Because all the work leveraged a common underlying product model, this prevented clashes and aided coordination. The company also harnessed the power of catalogs and libraries of stocks that were consistent across the project, e.g. tkMSA in Melbourne, Australia, found out what shipbuilding bulk material was going to be used by the shipyard in Canada and incorporated that into the library.

 

The numerous efficiency promoting features within ShipConstructor increased the number of items modeled and enabled enhanced detailing, all of which led to a “huge improvement” in output documentation. This was well received by all stakeholders including the Navy as well as the shipyard. An added bonus was that the 2D drawings generated from the 3D ShipConstructor model remained associatively linked so that any changes requested by the stakeholders could be easily accommodated.

 

The improved communication and coordination capabilities of ShipConstructor were easy to learn and were a natural evolution for tkMSA since the majority of design work in Australia is already done using AutoCAD and other Autodesk software products. tkMSA considered the fact that ShipConstructor is AutoCAD based to be a “big advantage.”

 

Following the frigate upgrade project the company now uses the ShipConstructor/Autodesk software for almost all projects including all pipework, HVAC and major foundation design.

 

tkMSA Chief Drafting Officer Simon Crook said that an added benefit of working with SSI is the supportive community and downloadable technical information found on SSI’s online information sharing and collaboration portal SSI Nexus.