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Proper planning is critical in the transition from 2D to 3D solid modeling. In many ways, planning is even more important than when engineers gradually converted from manual methods to 2D computer design in the late 1960's. Today, although less than fifteen percent of CAD work has converted to 3D, the shift is gaining momentum as 3D CAD systems become more powerful, user-friendly, and substantially more affordable.

Why take advantage of 3D design? Solid modeling technology can improve your analysis, design, manufacturing and, above all, productivity. It also significantly reduces the chance that models will require additional interpretation after completion. Furthermore, new systems add value to projects by enabling designers to reuse solid models for future projects.

To take advantage of the benefits of 3D solid modeling, here is a practical guide to help with the transition.

Step One: Understanding Solids

When planning the transition to a 3D design environment, you need to understand the importance of the solid model. In the 2D world, drawings are continually reinterpreted throughout a product's life cycle. With 3D technology, the solid model is the key element. Whereas drawings are just a different way of representing the model, the solid model may be tested directly by using analysis tools. Removal of hidden lines and mass properties are automatic. In short, solid models enable better understanding of look and function before physical models are made.

To transition to 3D you should first consider standardizing specifications for building models, defining dimensions, using parts libraries, features, and naming files. Standard practices increase efficiency by making it easier to reuse models and implement changes.

Step Two: Selecting Hardware and Operating Systems

Solid modeling requires substantially more computer resources than 2D CAD. Memory is often more important than processor speed, and insufficient memory can cause bottlenecking on your system's network. As more complex models are developed, the demand for memory will increase. Thankfully, memory upgrades are relatively inexpensive.

Will software support hardware features? Test software on platform alternatives and be sure to use your own data for testing. Don't overlook the ability of a system to be easily upgraded (you should expect the doubling of computer performance every 18 months). Also, be sure to check for the availability of third party software in your environment.

Your system should be able to integrate with other enterprise activities. Generally, CAD systems have few, if any, date-related calculations, but Y2K compliance should nevertheless be verified. (Data management, backup utilities and operating systems are the most likely areas for date problems.)

Step Three: Implementing Complementary Software

CAD tools are becoming easier to integrate with other CAD related components. This technology is evolving rapidly, and many ancillary products provided by CAD vendors may not keep pace with more general products for communications, data management and viewing. Be sure to verify systems before you buy.

It is also important to understand your data flow. Are translations between processes required? If so, how are they done? Changing all pieces of your process at once will create implementation challenges, but by developing pilot projects you will learn as you go.

Recognize that different parts of the process have different needs. The best design system may not be the best tool for a mold or tooling shop; changing all systems need not be done at the same time. Solid modeling, EDM, PDM, and internet applications (e.g., downloading parts from on-line libraries) can be planned and launched independently.

Step Four: Training & Technical Support

Training is one of the most important issues when transitioning to 3D design, and it should receive top priority. Although the investment in time and money may seem substantial, it will pay huge dividends in the long run by helping to ensure a smooth transition to different tools and processes. Experience has shown that inadequate or insufficient training can often lead to productivity problems that are ultimately far more costly.

Fortunately, an increasing number of 3D training options are available to CAD users. On-line and computer-based tutorials, for example, are resources that should be utilized. CAD software vendors are also building simulated learning environments directly into the software. Such an environment allows engineers to learn 3D design without worrying about "getting lost" in the software's system. Alternate training resources include vendors, dealers, consultants and in-house experts. The local Value Added Reseller (VAR) can play a critical role in the training and implementation of a new software.

Good technical support is also a wise investment. Consider your options - software vendor, dealer, independent consultant, or in-house support. Avoid the desire to be different just to be different, unless you understand the payoff.

Step Five: Handling Legacy Data

Legacy data can be an asset or a liability, and managing it properly is important. The approach you should take depends on the source of solids software and form of your legacy system. It is hugely beneficial to use solid modeling software that supports the conversion of existing drawings to solids.

Simple 2D drawings may be no more than a cartoon. If the user has "faked" data and not drawn auxiliary views accurately, the value is marginal. Depending on the software, automatic constraining tools may be able to fix problems for drawings created using single precision. Using parametric functions to align edges and features across views will be a great help.

Conversion of 2.50D drawings present many of the same challenges. The advantage of 2.50D is that drawings have been defined using 3D matrices to position the projection planes of each view. With these transformations, production of the solid model is straightforward.

Complex 3D wireframe and surface models will cause new challenges. The data is 3D, but the wireframe may be ambiguous and incomplete. Older wireframe systems may use curves and surfaces not supported by today's systems. You may need to sew or stitch surfaces to complete the conversion to a solid. Most likely, the old surfaces were not trimmed to a tolerance suitable for solid modeling and will need to be adjusted to finish the model.

Converting from solid modeling systems that do not support industry standard translators can be more challenging than other forms of legacy designs. The cost, time and effort to transition to solid modeling are important factors to consider before converting. Product revisions, product liability issues, and new product development all require a system that can be supported for years. The alternatives for dealing with legacy data are: a) convert everything, b) convert only as needed, c) convert only certain components, and, d) maintain your existing systems. Before converting, consider the correct mix of the these alternatives for your business.

Step Six: Defining Management's Role

Management must take a leading role to plan, coordinate, and direct the design interaction throughout the enterprise. Once the transition to solid modeling is made, design and manufacturing can expect a significant increase in productivity.

3D solid modeling provides new opportunities to customize products and expand product lines. Reusing models will benefit everyone from sales to logistics. 3D design also offers the potential to change working relationships with suppliers, making it easier to leverage for system advances.

Solid modeling and other engineering software can be your most important tools to explore new design solutions while improving your productivity and reducing costs.

But, plan carefully!

ABOUT LEE WHITNEY

R. Lee Whitney, MICROCADAM's Vice President, Planning, started at Lockheed-California in 1965 as an Associate Engineer in Project Design. Lockheed's initial development effort to provide interactive computer graphics for engineering and manufacturing, Project Design was later renamed CADAM. During the period that he managed CADAM development at Lockheed, the system grew from a single site in California to an international product with hundreds of customer sites.

When Lockheed formed CADAM, Inc. in 1982, Whitney became the Technical Director, where he performed product planning tasks and served as technical expert on all areas of CADAM products and CAD/CAM/CAE. During that time, he directed projects that led to Mainframe 3D Interactive, PROFESSIONAL CADAM, MICRO CADAM and many other CADAM products.

Before coming to MICROCADAM, Inc., Whitney was Director-Technical and Industry Affairs for Lockheed Information Systems Group (ISG). He provided consulting to Lockheed companies in CAD/CAM, Raster/Image Processing, product quality, software productivity, and information systems technology.

R. Lee Whitney holds a B.S. in Mathematics from Portland State College, an M.S. in Computer Science from the University of Southern California, and an M.B.A. from Pepperdine University.

ABOUT MICROCADAM, INC.

MICROCADAM, Inc., a wholly owned subsidiary of CADAM Systems Company (CSC) of Tokyo, Japan, develops and markets mechanical design automation software for the Windows environment. MICROCADAM, Inc. was founded in 1993 with a mission to make its customers more efficient, productive, and competitive by providing cost effective solutions for design and manufacturing. These tools help customers reduce product development costs and lead-time, while simultaneously improving quality, flexibility and responsiveness to market needs. MICROCADAM is customer-driven and has a long tradition in providing the best customer service and end user satisfaction.

CSC, founded in 1984, is a joint venture between IBM and Kawasaki Heavy Industries. CSC is the leading supplier of desktop mechanical systems in Japan.

MICROCADAM, Inc. has offices worldwide and distributes its products through a network of Value Added Resellers. Over 90,000 engineering professionals use MICROCADAM products worldwide. For more information or a product demonstration, contact your local Helix reseller today. Information is available on the MICROCADAM, Inc. web site (www.microcadam.com), or contact Beth Leitner, Manager, Marketing Communications, at (818) 253-2274, E-mail: [email protected].

PHOTOS AND CAPTIONS

A solid model can be created from three orthographic views in Helix99.

Traditionally 2D drawings have been prone to errors as illustrated in the optical illusion above.

Camera assembly created in Helix Modeling