3D - 2 Ways!

By Polhemus

Creating 3D digital models from physical objects has typically involved the choice between a laser scanner or a manual touch probe digitizer.  These choices include trade-offs between price, accuracy and ease of use.  Now, Polhemus offers a product option in each of these categories that is not only affordable but gives the engineer or graphic designer a fast and free-form method of digitizing.

  Touch probe digitizers (also called contact digitizers) mounted on the end of a CMM or articulating arm have been very popular for digitizing simple objects.  They are relatively easy to use, can be very accurate, and many have plug-ins to popular CAD and 3D modeling programs allowing them to be operated from within the software application itself.  On the downside,  they can be expensive and with the articulating arm’s limited range of movement, some surfaces can be difficult if not impossible to reach.  Polhemus recently introduced the PATRIOT™  Digitizer based on their 6DOF (6 Degrees-of-Freedom) position and orientation tracking technology.  The digitizing pen (stylus) can be moved freely in 3D space – around, under and behind objects small and large.  And at about $3,000, it is the most affordable digitizer on the market.

  Complex or large objects are usually not good candidates for touch probe digitizing.  It can be simply too time-consuming to collect the required number of data points to generate a good 3D model.  For these types of objects, 3D scanners (usually laser line scanners) are typically used.  Trade-offs exist here, too.  The majority of models are mounted on the end of a CMM or articulating arm and, as with the touch probe digitizer, can be very accurate.  They can also be very expensive and have the same limitations with lack of free-form movement due to the mechanical arm.  The Polhemus FastSCAN™ 3D laser scanner (again using the Polhemus 6DOF tracking technology)  is hand-held and completely free to move in 3D space.  And because it is not constricted mechanically, the FastSCAN is capable of scanning large objects easily.  In a recent example, a six foot long surf board was scanned, both sides, in less than ten minut es.  It is also about 1/5th the price of a typical CMM type scanner.

  The Polhemus 6DOF tracking technology, which has been used for military and medical applications for over 35 years, is now opening up new options in digitizing for the rapid prototyping and design markets.   For applications requiring extremely high accuracy or scanning certain types of metal, the CMM type scanners and touch probe digitizers will remain good choices.   But for companies involved in manufacturing of shoes, toys, consumer goods and other non-high precision products, the FastSCAN and PATRIOT Digitizer are affordable, easy to use digitizing options.   For complete details on the specifications for the PATRIOT Digitizer and the FastSCAN, contact Polhemus.

Polhemus
40 Hercules Drive, PO Box 560
Colchester, VT  05446
polhemus.com