Pro/JR. is geared toward designers of mechanical parts and assemblies who may be migrating from 2-D to 3-D software but need to stay in the $4,000 to $8,000 price range. Pro/JR. 2.0 is based on Pro/ENGINEER version 16.0, the most recent edition of PTC’s CAD/CAM software.

Several functions in Pro/JR. 2.0 improve how users work with features in 3-D design applications. For example, the software’s copying, mirroring, and patterning abilities make it easier to duplicate and reuse existing geometries within and between parts. The function can be applied to features individually or in a group.

These capabilities enable users to set up a standard library of features or components, according to product-line manager John Robbins. Engineers who work in the same company can then reference and apply those geometries in various designs in accordance with company standards.

Pro/JR. includes enhanced sketching abilities. Smart Drag, which is part of the sketching function, can help users modify a sketch, perform variational analyses, and evaluate design options. The software also provides Pro/ENGINEER’s full redefinition capabilities. Pro/JR. is suitable for companies in midrange markets, Robbins said, such as contractors employed by Pro/ ENGINEER users. The entry-level software, he added, also allows designers to use their models in Pro/ ENGINEER and upgrade later to the higher-end software when needed. Pro/JR. is available for Unix-based workstations as well as computers supporting Windows NT and Windows 95.

Kinetix has already introduced several new authoring tools. One product, 3D Studio Max, is a new version of Autodesk’s 3D Studio modeling and animation software that has been reconfigured for Windows NT platforms. The software enables users to create 3-D animations and multimedia content. Components called Space Warps aid in special-effects animation, while TrackView offers a time-line-based management environment for producing animations. In addition, 3D Studio Max has an extensible platform architecture that can install third-party plug-in applications automatically.

Kinetix also unveiled Hyperwire, an authoring tool for 2-D and 3-D Web titles. All Web applications created with Hyperwire are in JavaÑSun Microsystems Inc.’s Internet programming languageÑwhich enables them to run on Windows, Apple Macintosh, and Unix systems. Hyperwire also supports Virtual Reality Modeling Language (VRML) 1.0. Hyperwire-built titles are fully interactive in both 2-D and 3-D. Users can add features such as sales demonstrations, financial analyses, and support for interactive learning to their Web sites. Plug-ins developed in the Hyperwire environment enable users to link applications to relational databases, increasing the information available at a site. Although the commercial version of Hyperwire will not be available until later this year, users can preview the software on Kinetix’s Web site at http://www.ktx.com.

A third product being released under the Kinetix banner is Topper, a VRML player plug-in for Netscape browsers. Topper also can be downloaded from Kinetix’s Web site. Separately, Autodesk introduced Whip!, a plug-in browser with which users can view and share 2-D vector data via the Web. Designed for the Netscape Navigator and Microsoft Internet Explorer browsers, Whip! supports panning, zooming, and embedded universal resource locators (URLs). The plug-in can read Drawing Web Format (DWF) files, which are highly compressed 2-D data files. Through DWF files, CAD/CAM models, presentation graphics, and other types of images can be transmitted and viewed via the Internet. A preview version of Whip! can be downloaded from Autodesk’s home page at http:// www.autodesk.com.

Probe-lobing errors are a leading source of measurement uncertainty for CMMs equipped with such devices. The errors result from variations in the tiny displacement that occurs between when the probe’s stylus initially touches the part surface and when the probe is triggered to record the stylus’s position. During this interval, the force exerted on the probe bends the stylus. Because the magnitude of the force depends on the direction of the probe’s approach to the part, the amount of bending, displacement, and error varies accordingly.

Touch-trigger probes are used in about 98 percent of the approximately 30,000 CMMs installed in U.S. factories and research laboratories, according to NIST. CMM users can purchase CMMs with specialized probes to avoid probe-lobing errors, but they cost as much as 10 times more than touch-trigger devices. NIST researchers worked with scientists from George Washington University in Washington, D.C., to understand the mechanical workings of touch-trigger probes and the forces that displace the probe stylus. They discovered that lobing errors are caused by regularly repeated mechanical interactions that are strongly influenced by the direction from which a probe approaches a part to be measured. The resulting interactions generate highly repeatable systematic errors.

On the basis of this investigation, the researchers developed a detailed mathematical model of touch-trigger probes’ mechanics. The model enabled them to determine the probe’s variable movements and to compensate for the resulting measurement errors. NIST and CMM industry representatives are determining how the model could be made available to CMM users. The development of the model roughly coincides with the expiration of major patents on touch-trigger technology. When patent protection ends later this year, new suppliers are expected to enter the market and thereby reduce the cost of touch-trigger devices. If suppliers adopt the NIST model—which according to NIST representatives still needs fine-tuning—their probes could be far more accurate, too.

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