Robot Mechanisms and Mechanical Devices Illustrated - Profe Saul

Chapter 5 Tracked Vehicle Suspensions and Drivetrains 169
Figure 5-1 Basic steel link layout
showing pinch point
Figure 5-2 Effective hinge location
of all-steel track
Figure 5-3 shows the lowered pivot link with an added pocket for the
urethane road wheel.
The way to completely remove the pinch point is to make the track all
one piece. This is what a urethane track does. There are no pinch points
at all; the track is a continuous loop with or without treads. Molding the
treads into the urethane works for most surface types. It is very tough,
relatively high friction compared to steel, and inexpensive. It also does
not damage prepared roads. Ironically, if higher traction is needed, steel
cleats can be bolted to the urethane. Just like urethane road pads on steel
tracks, the steel links are usually designed to be removable.
Urethane by itself is too stretchy for most track applications. This
weakness is overcome by molding the urethane over steel cables. The
steel is completely covered by the urethane so there is no corrosion prob-