Distortion Correction of Magnetic Fields for Position Tracking
You can download the
Postscript version (432 kB)
You can also download the
PDF version (471 kB).
Electro-magnetic tracking systems are in wide-spread use for measuring 6D
positions. However, their accuracy is impaired seriously by distortions of
the magnetic fields caused by many types of metal which are omnipresent at
real sites. We present a fast and robust method for "equalizing" those
distortions win order to yield accurate tracking. The algorithm is based on
global scattered data interpolation using a "snap-shot" of the magnetic
field's distortion measured once in advance. The algorithm is fast (it
does not introduce any further lag in the data flow),
robust, the samples of the field's "snap-shot" can be arranged in any way,
and it is easy to implement.
The distortion is visualized in an intuitive way to provide insight into
its nature, and the correction algorithm is evaluated in terms of accuracy and
Finally, a qualitative comparison of the suceptibility of
a Polhemus and an Ascension tracking system is carried out.
Proc. Computer Graphics International (CGI'97), June 23-27 1997,
Hasselt and Diepenbeek, Belgium.
In case of problems
In case of problems, please don't hesitate to contact
(For instance, if your host is not registered by the world-wide Domain
Name Service (DNS), then you will not be able to ftp ...)
Sat Sep 10 15:54:08 MDT 2005