Visualization takes monstrous amounts of analysis data and lets you properly interpret those results by depicting them as reality—from car crashes to conveyors moving products, and more. In the process, product visualization speeds design and analysis time, enables more design alternatives to be viewed, and leads to higher quality products and processes. And it reduces design development costs—an expensive proposition where, for example, a prototype of a car seat typically costs $80,000.
Depicting reality is why engineers are turning to product visualization, also known as computer-aided industrial design (CAID) throughout the product development cycle. By doing so, engineers are taking advantage of the confluence of several fields, including art, image processing, vision research, computer graphics, and mathematics.
What is Product Visualization?
CAID is a broad term for the hardware and software technologies that combine numerous graphical display and imaging techniques for viewing voluminous amounts of engineering data in an understandable way. In short, the goal is to "turn engineering data into information," says Bill Boswell, director of Software Products Development for Engineering Animation, Inc. (EAI; Ames, IA). The resulting images can be viewed from several perspectives, viewed from within, altered, and animated.
|EAI's VisFly product visualizer lets M&L engineers interact with the entire Predator supercar assembly in real time. (Source: Engineering Animation, Inc.)|
|Using VisMockUp, the M&L Predator team can discover design flaws early in the development cycle before the supercar is rendered into physical prototypes. At the click of a mouse button, designers can examine parts and assemblies or "fly through" the entire visual model.Source: Engineering Animation, Inc.)|
CAID's product visualization differs from computer-aided design (CAD) solid modeling in three important respects.
First, CAD systems depict data exactly and generate usable images, but the images are not "real." To make the image photorealistic, the computer has to mathematically mimic the department cues our eyes see in real life, including perspective, shadow, overlapping objects, and haziness and loss of detail over distance. The result is a 2½D image, not true 3D and certainly not virtual reality.
Second, visualization is more a drawing conceptual tool than a dimensioning engineering tool. The user has to be pretty technical to work with a CAD package and focus on the actual parametric data, according to Boswell. Whereas, product visualization takes full advantage of the 3D data in the solid modeling environment, but makes it easier to view, analyze, and understand those data. "There are many more consumers of 3D data than there are creators," points out Boswell. "I see solids modeling tools as being in the creation end of the product development process, while product visualization tools make that information easily accessible to people."
Third, continues Boswell, "CAD systems have traditionally been part-centric; you can load parts and small and even moderate-sized assemblies, but not entire cars or airplanes." Contrast that with product visualization. EAI's VisMockUp, for example, is a digital prototyping software application that lets engineers interact with complete assemblies and "fly through" models to view components in detail. It also lets engineers check assemblies for part interferences.
Those "complete assemblies" can be entire vehicles. M&L Auto Specialists, Inc. (Two Rivers, WI) is designing and building America's newest, high-performance super car: The Predator. Using EAI's VisFly and VisMockUp, M&L can show visual animations and fly through a virtualization of this $150,000 car, capable of speeds above 200 mph. It can have the entire car "ride" on a virtual road, and with the wheels still turning, M&L can point-and-click on the display to remove car parts to see what's going on inside. Click the car body off and you will see the front suspension floating in air, hung by its suspension points. With kinematics and motion in full swing, M&L can see if the suspension arm interferes with the shock absorber. "We can make an assessment before making a decision," says Mark Gerisch, M&L's president and CEO.
Visualization also differs from simulation. While both can be dynamic—both for instance, can show animation sequences of parts coming together—simulation implies real-time operation and some amount of user control over the dynamics of the simulated environment.
Uses for Product Visualization
|Studio 8.5 from Alias/Wavefront is a CAID software product consisting of such capabilities as creating 3D geometry from scan "cloud" data collected from a physical model; displaying, manipulating, and cutting sections through very large cloud data sets; curve creation and editing tools; history mechanisms that let designers launch specific tools to create particular geometric elements; layers for displaying groups of data in different colors and with different attributes; draft angle/flange conformance tools; NURBS modeling that supports Booleans; 3D concept modeling from 2D concept sketches; and data exchange technology, including STEP translators and translators for direct transfer to third-party CAD systems (Source: Alias/Wavefront)|
Visualization is "redefining the product development process," says Al Lopez, business manager for Alias|Wavefront (Toronto, Ontario). "3D models, renderings, animation, and accurate manufacturing data now flow through the entire product development process of design, engineering, manufacturing, and to marketing, who can sell products before final tool production is done." Lopez sees four basic categories of visualization.
Concept visualization is an electronic way of producing sketches and simple 3D forms. Automotive stylists use visualization tools to put their concepts in a digital form on the screen in much the same way they would use markers, paper, airbrushes, and so on. Using a visualization package, the designer can air brush design details, even textures, with fully customizable, virtual brushes. By using tools based on non-uniform rational B-spline (NURBS) to trace the sketch, the designer can capture the evolving design for conventional 3D modeling tools.
Engineering visualization typically involves low-resolution visual tie-ins to product data management systems. Explains Lopez, "This level of visualization is not so much for getting a vision of what the concept will look like. Instead, it's for flying through engineering databases and being able to pick up a component for an assembly and then getting the bill of materials for that component or assembly. You're typically looking at shaded polygons. It's not very realistic imaging."
Scientific visualization is the compute-intensive visualization performed to evaluate data. For example, the medical industry creates 3D volumetric reconstructions from magnetic resonance imaging scans, NASA creates 3D views of earth's topography, and the automotive industry creates color-coded displays to visualize data related to computational fluid dynamics and crash analysis.
Design or CAD visualization displays a solids or surface model as realistically as possible. Generally, says Lopez, engineers and designers transfer their CAD model data into an animation and rendering environment. There, they can assign different surface properties, such as opacity and reflectivity, to the surfaces of the model, as well as assign color and texture. Shapes, paint, textures, and graphics from the finalized design can go through evaluation tools to check tolerances, curvatures, and continuities, ensuring machinable surfaces. These data can be exported to third-party CAD packages as needed. "This keeps design integrity throughout the product development process right on through manufacturing," explains Lopez.
The conceptual visualization can also be put inside an environment. For example, the industrial design department of Renault has been using Alias|Wavefront AutoStudio to design prototypes of new cars. For Renault's City-Fleet, six different vehicles were designed in AutoStudio in less than four weeks per vehicle. And instead of investing time and money building physical prototypes of the vehicles, Renault used Alias|Wavefront's Explore to blend computer-generated images of the concept vehicles with live action shots of Paris, including people crossing streets, shops, other street traffic, and even the reflections of umbrellas off the virtual cars' surfaces.
In the case of Renault and other OEMs, visualization does not try to eliminate all prototypes or all design models. Just the non-starters. "Visualization is an intricate part of our day-to-day process because our data goes through various stages of scrutinization," explains Tom Bradley, design senior, Surface Development Group, at the Chrysler Technical Center (Auburn Hills, MI). Chrysler is strictly a Dassault Systèmes Catia shop. So are its Tier 1 suppliers.
Bradley's group uses Catia's Image Design, Realistic Rendering, and Visualization Studio modules to, as he says, "eliminate some of the redundancies." He's referring to the redundancies of drawing a part in Catia, milling a model, verifying it, then having everybody scrutinize the model. Now, with all of the verification and analysis tools in the workstation, a physical model is not needed until late in the design development process.
These tools help Bradley and others scrutinize the wire frame, surfacing, proportionality, curve flow, gaps, panel-to-panel relationships, and even light reflections off a car driving down the road. Light reflections can show surface imperfections. "You don't want to see any bumps. You want the reflections to make sense," he points out. Using real-time analysis, Bradley can manipulate that surface to evaluate how the light reflections will change. He does this for the simple reason that "good curves give you a good surface, and a good surface gives you good parts."
Once Bradley is done with the design on the computer, then it's sent to conference rooms set up with Catia and big screens for people to sit and critique the designs.
Handling Too Much Visualization
|An infrared signal triggers the liquid crystal shutters in stereosscopic shutter glasses, such as these CrystalEyes from StereoGraphics. The shutters' opening and closing is synchronized with the right and left perspectives that are alternately displayed on the monitor. Many high-end workstations have a jack built right-in for the CrystalEyes emitter. (Source: StereoGraphics Corporation)|
Ironically, visualization has a problem. "It's counter-intuitive," says Bob Seltzer, director of Sales & Marketing for StereoGraphics Corp. (San Rafael, CA). The additional compute power now available on today's desktops can create too much visual data! The onslaught can be undecipherable. How do car parts fit together? How is the airbag inflating and enveloping the occupant's head? What pieces of a car in a crash are bending, breaking, and moving, and in what direction?
Adding stereoscopic viewing into the mix makes what is happening in the Z-axis perfectly clear. Seeing visualizations stereoscopically can be done in three ways.
Electronic shutter glasses use liquid crystal material to temporarily open and close a shutter in front of each eye in time with the right and left perspectives that are alternately displayed on the monitor. The glasses are wireless; an infrared emitter at the workstation sends synchronization pulses to a receiver on the glasses, which in turn pulses the left and right shutters on and off.
Many mechanical CAD and CAID packages used by the major OEMs support interactive stereoscopic viewing. SDRC I-DEAS Master Series 5, Hewlett-Packard's Visualize fx4 and fx6 OpenGL graphics engines, and applications from Catia, EDS Unigraphics, and Parametric Technology Corporation support StereoGraphics' CrystalEyes eye wear, which list at $995, including infrared emitter.
At the Advanced Research and Engineering Center of Ford Motor Company (Dearborn, MI), engineers use stereoscopic visualization to understand the multidimensional data files created from noise, vibration, and harshness testing. These files can contain from 50,000 to 500,000 visual elements—way too much for 2D viewing. Using CrystalEyes, Ford engineers can see how the steering wheel will vibrate or how a seat will shake by "climbing inside the car." Ford designers not only view suspension systems stereoscopically, but they also visually analyze every compartment and trim item for mechanical interferences.
Head-mounted displays (HMD) using liquid crystal displays are an immersive technology, meaning that the user is mostly cut off from the surrounding environment. They're okay for gamers, says Len Cardillo, product manager for VRex, Inc. (Elmsford, NY), "but working in an engineering environment with one of these on your head seems to be too confining for most people." HMD is what people think of when they hear about virtual reality.
Large-screen displays are reminiscent of those pictures from the 1950s of an audience wearing special glasses in theaters to see 3D movies. Unlike back then, no longer are two projectors needed—one for the left and one for the right perspective image view. Nor are red/blue or red/green anaglyph glasses necessary. Instead, the audience can see true-color stereoscopic scenes with inexpensive passive polarized glasses or electronic shutter glasses.
The VRex VR-2100, for instance, projects images up to about 14-ft wide. Costing just under $10,000, the projector can scale 640 X 480 video sources to 800 X 600 SVGA resolution, using 16.7 million colors, displaying stereoscopic 3D views in normal room illumination. Glasses are extra, ranging from $40 to $80 apiece.
At first, people are amused by 3D technology because it's novel, says Cardillo. "But they seem to remember the content better when it's in 3D."
Adds Dennis Harrington, director of Strategic Marketing for Computer Design, Inc. (Grand Rapids, MI), "People want to replace prototyping. If the visualization is accurate enough so it's believable and people can rely on it, then they can replace the prototype and get a return on investment in both speed-to-market and hard dollars. If the visualization product is not believable, then the product doesn't do you any good. All you've done is add cost to your prototyping process."
When evaluating CAID applications, don't get sucked into applications with fabulous color systems that you can't model with. And realize that as with CAD itself, new visualization tools—features and functions—are being introduced all the time. Alias|Wavefront AutoStudio, for example, includes features required by the automotive industry. One module, EvalViewer, lets designers evaluate and process very large "cloud" data sets, which are a result of reverse engineering from physical models. Surfaces generated from these cloud data can be displayed, manipulated, and cut into sections, then imported into other CAID and CAD tools.
In general, ensure that the CAID applications can be integrated to a variety of existing data sources and that geometry data can be passed to downstream engineering and manufacturing systems. In this day of multiple suppliers working in collaborative automotive design environments, says Boswell, "you want to have the advantage of leveraging your 3D data as an asset throughout your organization." For that, Boswell says you want the product visualization tools to be: