Cletrac differential steering - SolidWorks animation 

Here is an animation of the Cletrac "controlled differential steering".
Red - output shafts
Yellow - steering brakes
Dark blue (translucent) - differential housing
Light blue - idler wheels
0-11 sec: straight forward motion;
12-23 sec: left brake applied - left output turns slower, right output turns faster;
24-35 sec: right brake applied - right output turns slower, left output turns faster.
This steering system is very basic and robust.
More reading:
www.scmec.us/pd...
www.livesteammo...
The steering system has been used on many vehicles, such as dozers, tanks and also the Kleines Kettenkraftrad HK 101 (German half track vehicle). And on the M113 Armored Personnel Carrier.