Synchronous technology can move between history-based and direct modeling. The next step in realistic CAD — stereoscopic design? ... And more
Synchronous technology sheds light on surgical laser design
Energist Group in Nyack, N. Y., recently moved from several different CAD packages to standardize on one. The intent was to improve the design and manufacture of its surgical lasers and light-based devices for hair-removal and skin treatments. The company found that using multiple packages tended to bottleneck designs, which raised costs, lowered quality, and increased time to market. Theses issues were critical because Energist was increasingly competing against firms that did not comply with ISO, FDA, or Health Canada standards. The firms’ inexpensive, unapproved products were hurting Energist’s bottom line.
The company turned to Solid Edge 3D CAD from Siemens PLM Software, Plano, Tex., which came as a suite that included part, assembly, and sheet-metal modeling, as well as drafting, simulation, and piping design.
Energist devices contain anywhere from 76 to 3,500 parts, and some components and assemblies are provided by outside suppliers. Energist Chief Technical Officer Andrew Thomas estimates that the company’s designers use Solid Edge’s synchronous technology for about 95% of the design process. (The remaining 5% is piping and wire-harness design). Synchronous technology lets users easily move between constraint-driven and history-free modeling.
“Not only is it easier to design parts and assemblies from scratch using synchronous technology, another important advantage is how quickly we can process engineering change orders (ECOs). And it doesn’t matter whether the design was done using Solid Edge or a third-party CAD package,” says Thomas. “For example, when we needed to reduce the size of a cooler, it took only 2 hours to relocate the internal parts and assemblies using Solid Edge. Drawings and STEP files were distributed to manufacturing the same day. Making a change like that would have taken a few days previously.”
In another example, the company needed to quickly create a prototype of a component that had originally been modeled in another CAD package. “The original file had two design errors — a missing surface and an overlapping edge,” says Thomas. “Without synchronous technology, we would have had to understand the history of how that piece was created. Even then, the changes would have been difficult to make. In fact, some individuals thought we would have to remodel the part. But it only took a few minutes to import the file and fix the errors.”
Energist also uses Solid Edge simulation capabilities to quickly evaluate real-world performance issues such as how a temperature drop from ambient to 37.4°F will affect the material in a hand piece. According to Thomas, answering such questions using software eliminated the need for at least one physical prototype for this design.
“The combination of faster ECOs and fewer physical prototypes lets us get new products to market in only three months. Previously, it took 19 months,” says Thomas.
Stereoscopic designs look like real objects
zSpace uses a proprietary stereoscopic display, trackable eyewear, a new type of direct-interaction stylus, and software that lets designers see “solid” models as if they were in open space. The full color and high-resolution models can be directly manipulated. The technology gives users a natural way to navigate, grab, slice, carve, zoom, and explore models. The immersive zSpace lets users interact with 3D applications just as naturally and intuitively as they would with real physical objects. zSpace can enhance and improve user workflows by letting designers and engineers represent their ideas more effectively and realistically than possible with today’s 2D displays.
The best way to learn 3D modeling? Don’t focus on the software
At least, at first. That’s part of the philosophy at a new instructional site that emphasizes the broader concepts of 3D graphics before delving into the dashboard of a particular CAD application.
“People just starting out in 3D modeling are forced to wrap their brains around a lot of unfamiliar concepts,” says the author of the PolyPlane instructional video series Gabriel Mathews. “At the outset, stepping back and understanding the process of modeling in general actually makes learning an application a lot less frustrating.”
The first series of free videos at PolyPlane.com — called “Preflight” — gives the overall lay of the land (or grid, in this case) for students before they even get into the cockpit of a modeling application. Each 3 to 4-min lesson focuses on a basic concept in the problem of generating 3D geometry.
“We try to build an overall framework of modeling for the newcomer. We don’t want to just define a term but show why it’s important and how it works in the big picture,” says Mathews. “Once users have the big picture, it makes it much easier to take command of the software when they finally approach it, because they know what to look for. A short time on PolyPlane lets users pick up any kind of modeling application.”
Applications can include engineering packages such as SolidWorks or Pro/Engineer, curvilinear Nurbs-based applications like Rhinoceros or Alias, or tools for animators and artists like 3DStudio Max, Blender, or Maya. Knowing more about the basic tenets of 3D can also help students make smart choices about which software is most in line with their interests, Mathews says.
Mathews says there are dozens of other sites with modeling tips as well as tutorials put out by software developers, but he finds that too often they expect the viewer to already have a background familiarity that amateurs usually lack.
“Usually tutorials are about 45 min long and loaded with acronyms and technical jargon,” says Mathews. “An amateur is not going to know what a UVW map is. It’s discouraging to slog through a long tutorial and only grasp 50% of it, And if the instruction is too centered on the software of a particular brand, it also tends to assume the viewer has a working knowledge of modeling already.”
In contrast, each short PolyPlane video explains in simple terms and clear illustrations another piece of the puzzle. Visitors to the Preflight Series are said to be able to accumulate a solid background of the principals in a few spare moments during the week, without opening up a modeler app.
“A lot of modeling is problem solving, more of a mental maneuver, like how to break up the object you want to make into more basic geometry, for instance.” says Mathews. “The modeler is not going to do this for users. It’s something they learn to visualize.”
Each video imparts more know-how such as why Nurbs are important or why it matters how you set up an origin point a particular way. As users get into modeling the rules of thumb eventually become second nature. In starting out, these rules often become the roadblocks to understanding the software.”
Learning by doing eventually is part of the ride, too. PolyPlane has longer 2-hr Series, called “Sketch-to-Model,” which put the basics to work in a practical, step-by-step modeling project. Here it helps to follow along in a modeling application, Mathews says, but it doesn’t much matter which application.
PolyPlane plans new free videos every week throughout 2012 including more advanced projects and other design resources for the beginner. Check out other video lessons at www.polyplane.com.
Simulation software helps build amphibious vehicle for Arctic-oil facilities
Arktos Developments Ltd. (ADL), Surrey, B. C., Canada, the designer and manufacturer of an amphibious vehicle known as the Arktos Craft, uses simulation software to prepare its vehicles to operate in some of the world’s most environmentally demanding locations. Originally designed as an amphibious evacuation craft for Arctic offshore oil facilities, the Arktos Craft can move from frigid –50°C (–122°F) temperatures through burning flames, and back again, as in the case of evacuating a burning oil rig. Additionally, the Arktos Craft can easily navigate ice-rubble fields, ice ridges and open water — and can even climb up or down vertical steps — making the Arktos a highly capable exploration craft. Autodesk Simulation from Autodesk Inc., San Rafael, Calif., provided the mechanical simulation software.
Valmont West Coast Engineering (Valmont), Delta, B. C., Canada, which provides finite-element-analysis (FEA) services to ADL, was responsible for predicting vehicle performance in severe environments. “We used Autodesk Simulation to predict critical stresses for the Arktos at extreme temperatures and loading conditions,” says engineer Ioan Giosan at Valmont. “After finding an optimal design using FEA methods, we relied on physical testing and field use to validate the accuracy of our results.”
The key to the Arktos Craft’s mobility is an articulated arm between the vessel’s two main compartments. As the craft climbs up onto an ice shelf from the water, the hydraulics in the arm help push the front unit of the craft out of the water so the special track spikes can grab the ice.
Using the multiphysics capabilities of Autodesk Simulation, Valmont could show ADL engineers how thermal stress caused by temperature extremes would combine with mechanical stress in the articulated arm. Additionally, the arm would see repeated compressive and tensile loading so Valmont also analyzed fatigue life using the Autodesk Simulation multiphysics tools.
“We continue to modify the original Arktos design for each of our new customer’s special needs,” says ADL President Bruce Seligman. “Autodesk software makes it easy for us to design new attachments for the craft, and then simulate how those modifications will affect performance. Sharing early concepts and results with stakeholders digitally is a critical part of our development workflow today and it is all powered by Autodesk software.”
Arktos Craft units are currently operating in Alaska, China, and the Caspian Sea in Kazakhstan.
Modeler for organic shapes
Freeform Version 12 adds over 50 new features and enhancements. It lets users efficiently and cost effectively create complex models, with organic and manually sculpted looks that can’t be modeled in Nurbs.
Highlights include faster and more-flexible deformation and roughing-out tools and a bigger toolset for developing engineered production-ready organic models across representational types. For example, uses can break up polygon models for articulation, interactively optimize mold pull direction, fix moldability problems, and develop complex parting surfaces. In addition, Version 12 lets users interoperate between polygon models, Nurbs, and voxels.