patrick@longs.LANCE.ColoState.EDU (patrick fitzhorn) (06/29/90)
We are looking for info on automatic digitizers capable of digitizing objects with holes and voids. These objects typically have volumes no larger than 200x200x200 mm. It would be nice to have both an accuracy and resolution of about 0.5mm. We really do not care how much time the digitizer requires; several hours would be more than acceptable. We are concerned however, that the digitizer be able to "probe" into holes (we understand the mechanics and trigonometry involved and know how difficult this is). As a test case, we would like to digitize a human skull with enough accuracy to capture the sutures, dentition, and orbits. If you know of such a digitizer, we would certainly appreciate hearing from you. Patrick Fitzhorn Department of Mechanical Engineering Colorado State University Fort Collins, CO 80523
xanthian@zorch.SF-Bay.ORG (Kent Paul Dolan) (06/30/90)
In article <7746@ccncsu.ColoState.EDU> patrick@longs.LANCE.ColoState.EDU (patrick fitzhorn) writes: >We are looking for info on automatic digitizers capable of digitizing >objects with holes and voids. These objects typically have volumes >no larger than 200x200x200 mm. It would be nice to have both an accuracy >and resolution of about 0.5mm. We really do not care how much time the >digitizer requires; several hours would be more than acceptable. We >are concerned however, that the digitizer be able to "probe" into >holes (we understand the mechanics and trigonometry involved and know >how difficult this is). > >As a test case, we would like to digitize a human skull with enough >accuracy to capture the sutures, dentition, and orbits. If you >know of such a digitizer, we would certainly appreciate hearing from >you. > >Patrick Fitzhorn >Department of Mechanical Engineering >Colorado State University >Fort Collins, CO 80523 Probably by far the easiest way to do this would be to hire time on a local hospital's cat scanner. They have the scanning = digitizing tools and most have software to return a fairly nice solid model representation that can be viewed from lots of angles. The tough part will be capturing their file structure into yours. Since cat scanners solve this problem so well (for anything that can accept the radiation), and the math and so on is quite sophisticated, this is probably a wheel not worth reinventing. For objects that can't take the radiation, but can withstand immersion, using an NMR scanner on your object in a container of water might give you a negative image of suitable quality. Same caveats as above. Just a suggestion, but it might save you a lot of headache. Kent, the man from xanth. <xanthian@Zorch.SF-Bay.ORG> <xanthian@well.sf.ca.us> -- Yes! Nicely explained, even I understood it! Thanks. -- Charlie Sorsby
james@fungus.bsd.uchicago.edu (James Balter) (07/03/90)
While using CT scanning may be possible, it still may not meet the specs you requested (eg. seeing the "sutures", 0.5 mm. resolution). Most commercial CT scanners achieve a pixel of 0.7*0.7 mm., with slice separation varying (but probably not better than +/- 0.5 mm. accuracy). James Balter james@rover.bsd.uchicago.edu "If the hat fits, slice it!"