HarnVis

We design, develop and support all the HarnWare and HarnVis software for Raychem (now a part of Tyco Electronics). HarnVis is a 3D modelling system for visualising harness designs generated by HarnWare - a comprehensive electrical wiring harness design system used by over 1,000 engineers in more than 300 companies in 30 countries around the world. See the Tyco Electronics HarnWare www.harnware.com web site for further details.

Click the above thumbnail images to view two sample 3D models from HarnVis. The free OpenHSF viewer will be downloaded when you first click one of these links. While the OpenHSF viewer install file is 1.6Mbytes, the two sample OpenHSF files are less than 50 Kbytes each. Therefore, it may take sometime to view the first OpenHSF file, but then other files can be downloaded and viewed in less time than many simple Web pages.

HarnVis automatically generates to-scale 3D models which provide “virtual prototypes” of harnesses designed by HarnWare using 2D non-scale drawings. With HarnVis the user can see what a harness will look like with all parts shown to-scale. This reduces the potential for errors. Sometimes alternative Raychem products suggested by HarnWare have different overall dimensions which can affect the fit within the equipment. When the alternatives are checked in HarnVis, certain options may be found to be too large for the available space envelope.

HarnVis gives a good representation of most moulded parts when fitted to any suitable size of adaptor and harness leg. When two or more alternative Raychem boots are available to fit the mating parts, HarnVis makes the reason for the choice much clearer. For example, a small boot may seem a reasonable choice until it is seen straining to fit onto a large adaptor in HarnVis. By clicking a part in HarnVis, the key part dimensions can be displayed along with such data as Raychem part numbers, materials, finishes, adhesives, etc.

HarnVis 3D models can be viewed from any angle and centred on any part. Views are rendered in colour with lighting effects, which are very realistic. The smoothness of the model can be adjusted, as can the position of the light source and the perspective angle.

3D views are ideal for quotation drawings, presentations, exhibitions, etc. They have a more immediate impact than 2D schematic drawings, especially for those who are not trained in reading engineering drawings. 3D views can be saved to file on disc or copied to the Windows clipboard for pasting into Visio and other Windows programs such as Microsoft Word.

HarnVis can also save 3D geometry to IGES files which can be imported into most CAD systems including Pro/Eng, Catia, Unigraphics and SolidWorks. This enables wiring harnesses to be included in 3D models of mechanical assemblies, allowing space envelope checking or clash detection. Previously most users resorted to modelling simplified moulded parts at a "typical size" in their 3D CAD systems whereas the models of moulded parts generated by HarnVis are to the actual installed size for the particular mating adaptor and cable diameters.

The 3D modelling methods used in HarnVis are finely tuned for this particular type of geometry. These methods are much more restrictive than those used in general purpose 3D CAD systems such as SolidWorks, SolidEdge, Inventor, ProEngineer and Medusa. But HarnVis is very much easier to use; the user works in a simple 2D Visio/HarnWare environment and 3D models can be produced fully automatically in only a few seconds whenever the user wishes. The 3D complexities do not get in the way or slow the user down as it is an optional output, rather than a working environment imposed upon him in the manner of most general purpose 3D CAD systems. 3D geometry is inherently difficult to work with, especially in a parametric form and, therefore, ease of use is still a serious constraint that limits the use of general purpose 3D CAD systems.