Product Design

How Open are Open 3D Data Formats?

12 Jan, 2006 By: Jeffrey Rowe

Examining the pros and cons of each option, Part 1: JT


Amidst all the hubbub, hoopla and hype surrounding so-called open data formats, I've wondered just how open are these formats, really? In the next few installments of MCAD Tech News, I'll take a closer look at this issue. This time around, I'll examine UGS' JT format. Next time I'll cover Dassault Systemes' 3D XML. And in the third installment, I'll report the results of testing to determine which really is the most open.

The JT Initiative
It's no secret that interoperability issues within and between organizations using different software applications to conceive, develop, engineer, manufacture and maintain products cost tens of billions of dollars annually. Initiatives to improve interoperability in these heterogeneous application environments have been bandied about for years. Although it is very doubtful we'll see a universal solution, groups have tried to tackle this huge problem, and JT is but one attempt. Supporters describe JT as the world's most widely used format for sharing lightweight 3D product images and manufacturing information.

In the wake of the seemingly endless stream of big and small so-called open 3D data formats, the JT format has enjoyed surprisingly wide acceptance. That's not to say that JT doesn't have its detractors, but that's a topic for another column.

For those not familiar with it, JT is an extension of JT Open, a group of software vendors, users, universities and other parties spanning the PLM chain. Any interested individual or organization can join JT Open. Software developers in the group want to develop JT-enabled applications for sale to other member companies; other companies want to make JT a standard part of their business processes. These various entities, through an "open distribution" of technology and business model on a relatively level playing field, are able to share 3D data through the medium of the JT file format for visualization and collaboration throughout the product lifecycle.

Growing Use
JT is becoming a mature, lightweight data format that already enjoys relatively widespread use in the automobile and aerospace industries, but seems equally suitable for other mechanical design, engineering and manufacturing CAD applications because JT files can be exported from just about all major CAD systems.

Software product developers have created translators from many MCAD systems to JT. Though not perfect, when properly implemented, JT can function as the only format common to the major applications that might be used in an enterprise. JT data can be very lightweight, holding little more than facet data, or the data can be richer and hold associations with the original CAD information, assemblies, product structure, geometry, attributes and metadata. It also supports multiple tessellations and level-of-detail generation.

The whole JT movement got a big boost last year with the announcement of an alliance to ensure interoperability between Autodesk's DWF (design Web format) and UGS' JT file format and their associated viewers. This alliance found two long-time competitors joining one another's open viewer initiatives -- UGS' JT Open Program and Autodesk's DWF Developer Program. It's still a mystery about the degree to which each company will integrate and interact with the other's data format and viewer. Today, it's not clear whether the companies are simply adding import/export functions or are going further and actually integrating one another's viewer formats.

JT2Go Viewer
JT2Go is the free, lightweight, CAD-neutral tool for viewing 3D JT files up and down the supply chain. Introduced in late 2004, it was developed by JT Open members who had a mutual desire to extend JT use throughout PLM. The JT Open community supports JT as an industry interoperability standard format for geometry-centric business processes (workflows) and for enabling viewing and interacting with design data. Before JT2Go, only UGS customers or JT Open members could tap into JT. The intent of JT2Go was to enable a potentially much larger user base.

With some degree of fanfare at its annual user conference last May, UGS announced JT2Go PLM World Edition. The new edition brought additional functionality beyond standard JT2Go by adding JT document-publishing capability for authoring a variety of Microsoft documents with embedded JT2Go viewers.

The new -- and free -- edition makes the visualization and collaboration capabilities of JT2Go available to a much wider group, such as executives, managers, business partners and suppliers who probably would not typically use 3D viewing tools. JT2Go does have limitations. For example, it does not support markups - a capability that is essential for comprehensive design communication.

Basic 3D measurement and 3D cross-sectioning are included in the no-charge download for a 90-day period to demonstrate some examples of the added capabilities available with Teamcenter Visualization. Following the 90-day period, these features are disabled. So, to keep the added functionality, you'll either have to join JT Open or upgrade to Teamcenter Visualization.

JT2Go is somewhat shrewdly designed as an introduction to the capabilities of JT and is a bridge to its big brother, Teamcenter Visualization. Teamcenter Visualization is a much more comprehensive suite of process-oriented visualization products tightly integrated into other UGS Teamcenter PLM products. Teamcenter Visualization offers tools for specialists who need to work closely with design data but have special process needs, such as conceptual design and clearance/interference analysis.

We've not yet seen the response to this from the competing technology, 3DXML, and its proponents, Dassault Syst

AutoCAD Tips!

Lynn Allen

Autodesk Technical Evangelist Lynn Allen guides you through a different AutoCAD feature in every edition of her popular "Circles and Lines" tutorial series. For even more AutoCAD how-to, check out Lynn's quick tips in the Cadalyst Video Gallery. Subscribe to Cadalyst's free Tips & Tools Weekly e-newsletter and we'll notify you every time a new video tip is published. All exclusively from Cadalyst!
Follow Lynn on Twitter Follow Lynn on Twitter



Poll
Which file format do you use most often for CAD drawing/model exchange?
Native format
PDF
3D PDF
DWF
STEP or IGES
JT
IFC
Other
Submit Vote