Easy-to-use software converts 2-D art to 3-D relief.

Producers of plastic bottles and many other products can now incorporate decorative relief patterns far more quickly and less expensively than is possible with conventional methods. Instead of requiring a skilled craftsman to painstakingly engrave a relief pattern onto a mold, the entire process, from design to machining, can be performed electronically with new CAD/CAM software from Delcam, Inc., Eastlake, Ohio.

Delcam is the U.S. office of Delcam International in England, creator of DUCT5 CAD/CAM software for surface modeling and NC machining. Delcam's most recent product release is ArtCAM, which appeared commercially in February after six months of beta testing. Like DUCT5, with which it is compatible, ArtCAM runs on Unix workstations. By the end of this year, however, Delcam expects to make it available for PCs.

2-D TO 3-D IN EASY STEPS

Delcam spokesmen say the process takes only a couple of hours to learn. The first step in using ArtCAM is to enter the 2-D artwork into the computer using a standard document scanner connected either directly to the ArtCAM workstation or to a PC. (Standard network protocols can be used to transfer the scanned art file from PC to workstation.)

The art does not have to be highly refined. ArtCAM can convert thick and thin lines to a uniform weight, and other imperfections can be rectified by "cleaning up the pixels," as a company source puts it.

The first step in generating the relief is to color-code various areas of the artwork that are to be represented in relief. This can be done by electronically "painting in" different areas, using different "brush" sizes manipulated via the mouse. Or you can use the automatic "flood-fill" function by clicking on an area of the art, which automatically becomes fully colored within its boundaries.

The next step is to assign a shape profile to each color. A color may represent a flat area at a specified height, a square profiled area with rounded sides and specified height, or a rounded profile (convex or concave), with specified maximum height and angles. In addition, a scale factor is assigned to govern the fullness of the profile. These specifications of heights, angles, etc. may be edited later on for esthetic effect.

After ArtCAM processes the data, the generated art profile can be viewed as a shaded 3-D image, which can be panned, zoomed, and rotated in real time to examine the relief in detail and from any angle. Individual colors can even be processed and displayed separately, allowing minor changes to be made and checked without needing to process the whole design.

The final relief is then transported into DUCT5, where the relief can be "wrapped" around the product contours and seamlessly integrated into the product surface. Last, the DUCT5 machining module can be used to generate NC codes for cutting the mold cavity, including both the overall shape and artwork detail. (Eventually it will be possible to output machining instructions directly from ArtCAM.)

ArtCAM software costs around $11,000. DUCT5 costs $25,000-40,000 and includes modules for finite-element meshing and for 2-D drafting (DUCTMold) of runners and mold-cooling channels. Delcam has also been working of late on integrating DUCT5 with rapid-prototyping systems such as stereolithography and laminated-object manufacturing.

Delcam will be featuring ArtCAM at upcoming trade shows, including Mold Expo in Detroit in September, AutoFact in Chicago in November, and Interplas '93 in Birmingham, England, also in November. (CIRCLE 11)