Marine Technology Notes: Virtual Vessels

Dazzling computer-generated special effects in movies like Titanic, the Star Wars series and the recently released Matrix Reloaded are the flagship examples of the place computers have in generating images. Less obvious is their use in broadcast TV, where they are regularly used to stretch production budgets, like generating digital snow for Los Angeles-based shows that are set in colder climates. What about the marine world? Is the power of computers to create stunning yet believable images having any effect in the world of yacht design?

For naval architects, computer-aided design (CAD) has been around for a long time; most yacht designers have long since taken advantage of its power to define the basic outline of a boat hull on screen. “Hardly anybody draws by hand anymore,” said Bob Perry, a designer in Seattle. In fact, “The yards don’t want any hand drawings.”

Of the computers in his office, Newport, R.I.-based naval architect Eric Sponberg said, “They are a godsend and a curse. I spend 95 percent of my time at a computer. I’m distressed that I have to spend so much time at the machine.” Yet, in the next breath, he’s quick to admit: “I don’t know what I’d do without cut and paste.” Sponberg will often reuse elements of line drawings, rather than drawing them again from scratch. “The thinking has already been done.” If he has to make a change in a drawing, he’ll copy, say, a frame detail from a previously completed image and paste it into the drawing that needs the change.

Sponberg said that one builder he works with didn’t have a computer lines-drawing program, like AutoCAD, until last year. That builder would only accept blueprints. When a change was necessary, Sponberg would have to make the modification in the drawing, output a new blueprint and mail it. The process took a week. Now that the builder has computerized, Sponberg sends the changes via email in a matter of seconds. “The tools make decision-making very fast for the customer and the builder.”

But two-dimensional lines-drawing programs have been around for a decade or more. Where things really have changed for designers and design firms is in the area of three-dimensional modeling or rendering. Software programs that create 3-D images of hulls or interiors or whole boats have become an important element in the yacht design process. “For us it has become a huge aid in design,” said Bruce Johnson, chief designer at Sparkman & Stephens in New York. “We have a man full time just dealing with interior and exterior renderings.”

The 3-D images produced by rendering programs look so great you might think they are used solely for their promotional value. But, in fact, a program like Rhinoceros not only provides the model that allows a realistic 3-D rendering of a boat to be produced, but it can be incredibly helpful to a designer in completing the nitty-gritty detail work required of a good design. Three-D modeling programs produce pictures in a format called nonuniform rational B-splines (NURBS). According Robert McNeel & Associates in Seattle, the firm that developed Rhino, NURBS are “mathematical representations of 3-D geometry that can accurately describe any shape from a simple 2-D line, circle, arc or curve to the most complex 3-D organic free-form surface or solid.” In other words, when you are finished modeling a vessel in a program like Rhino, you’ve got a 3-D image that looks like a real boat.

While you might think that designers would draw a lines plan first and then work on a 3-D rendering, many of them start with a 3-D program. “We’ll model it in Rhino,” Johnson said, “to make sure things like deck cambers make sense.” After the 3-D model is completed, Johnson and his team then import a design into a lines program like AutoCAD for further refinement. When Johnson wants to maximize the look of a 3-D rendering, he will then import the image into Adobe Photoshop or Adobe Illustrator and improve colors, blends and lighting.

Designer Perry will even use a 3-D model to provide the raw material for making 2-D lines drawings. “You create a model in 3-D, and you saw it up into 2-D shapes,” Perry said. “Almost all these computer technologies take more time, but they give you a better design product.” According to Perry, all the time and computer work is an improvement, “because you can focus on the details better.”

Another area where 3-D modeling is used is giving owners a feel for how something will look. Sometimes during the design process, owners will want to see how a certain aspect of the design works, often an interior. “An owner had a question about his pilothouse design,” Johnson said. “How open is it going to be between the pilothouse and the main salon? He couldn’t visualize it.” One way to answer those types of questions is to draw a perspective of the interior. Before 3-D modeling, such a drawing was not a quick task. “Laying out a perspective drawing by hand was a time-consuming process,” Johnson said. Now, Johnson’s team will print a 3-D interior drawing and then hand-color it with markers, the whole process taking far less time than was needed previously.

Another aspect of designing with 3-D software is the ability to model a piece of gear or a part or even the molds for fiberglass-boat manufacturing and then go directly to a computerized milling machine. According to Daryl Wilbur, president of Virtual Marine Concepts of Bristol, R.I., “We can take a 2-D drawing and then turn it into 3-D file format that milling machine can read. It becomes a full-blown engineering drawing.” The 3-D drawing can then be used to set up the pieces for building boats. “A company like North End Composites can make a plug and molds. Everything you need for production tooling,” Wilbur said.

As for the future, Perry has his own idea of what he’d like to see. “I’ve always envisioned a computer which would project a hologram of a boat design.” Once the design was where you wanted it, Perry said, you would “spray a light-sensitive spray that solidifies on contact.” The spray would harden, and the result would be a model, or maybe even a full-sized boat, ready for finishing. As technology moves forward, who knows, maybe some day Perry’s spray-a-hologram concept will be the way boats are designed and built!

By Ocean Navigator