From: jace@robots.ox.ac.uk 
Subject: RE: TECH: tetherless trackers (art. no. 6767)
Date: October 16, 1995


From: jace@robots.ox.ac.uk 

I have developed a "no wires" 6 DOF tracker.  The system uses a CCD
camera to image a set of six infrared LEDs on the user's head.  The
image positions of these points are used to recover the pose (position
and orientation) of the user's head.

The algorithm I use requires a minimum of three points, but can use
any number of points for better noise rejection, and takes about 3ms
per image.  The present system has a bandwidth of 25 HZ and can track
head rotations of up to 400 degrees per second with the user one meter
from the camera.  Both of these figures are limited only by the camera
field rate of 50 Hz.  The system runs on a single C40 based
framegrabber.

I am currently working on extending the tracker to use natural
features in its tracking.  This system could easily cover a very large
working volume by using an active camera or multiple cameras.  It also
offers an excellent way to track multiple operators.

An example of a basic visual telepresence application using this
tracker can be seen on my WWW home page:

http://www.robots.ox.ac.uk:5000/~jace/

I will add the paper describing the work as soon as it is published.
Please e-mail me with any questions or remarks.
____________
Jason Heuring                   jace@robots.ox.ac.uk
Robotics Research Group         http://www.robots.ox.ac.uk:5000/~jace/
Oxford University               phone: +44 1865 273168
Oxford OX1 3PJ                  fax:   +44 1865 273908