A moon buggy showing how to use the directional transmission.
This chassis was the
original
directional
transmission. I wanted
to use one motor for forward motion
and steering. 
This chassis is slow
but powerful.

I used chain links to
connect
all of the wheels.

Here is a close-up of
the gearbox.

The rubber band
helped stop the gears
from slipping.
Here is a movie
(MPEG) of the buggy using
the directional transmission.