So in the time I have been away I managed to rebuild the robot that started this whole mess -- Harve.  We are now on iteration three and some big changes have been made.

So gone are my homemade wheels and on go some snazzy anodized beadlock wheels from the world of off road RC racing.  Had to make my own axle adapters but that was pretty simple.  The side plates are now 3/8" thick 6061 aluminum cut on a waterjet (thanks to Albuquerque Waterjet! -- http://www.waterjetcuttinginc.com/home.html).  The top plate is now carbon fiber from RockWest Composites.  (They mostly do tubing but they have peel-ply plates and a 12x12 square was $20! -- http://www.rockwestcomposites.com/browse/carbon-fiber-plate)  Again cut thanks to waterjet technology.

These are the wheels.  Really well made and great for holding these off road tires in place.  Not free unfortunately... (http://www.vanquishproducts.com/slw-v1.html)

Also added a screw terminals to all of the connections not made with traditional Arduino Uno shields (which is now the motor control/half-bridge and the shield for an XBee radio -- http://www.sparkfun.com/)  If anyone is interested I will post something later about how I built it and the part numbers for the screw terminals.

Last but not least was the addition of carbon fiber angles to support the ultrasonic sensors.  Mounted with a single screw for small angular adjustments, if necessary.

And something to note when working with carbon fiber - its light, strong and conductive (very conductive!)  I had a rather nasty short that took a while to track down and finally found it with a ground touching the carbon fiber plate.  Now there are nylon standoffs between all electronics and the carbon.