Important video to view and listen: https://alvanon.com all the best, Don -- Don Brutzman Naval Postgraduate School, Code USW/Br brutzman at nps.edu Watkins 270, MOVES Institute, Monterey CA 93943-5000 USA +1.831.656.2149 X3D graphics, virtual worlds, navy robotics http://faculty.nps.edu/brutzman