Today’s invention is a tanktrack link which has a roller embedded in it.
This roller (red) contains a lock which can be activated wirelessly, so that as the track is lifted off the ground, the roller falls into a different position vertically (and is again locked). Normally the rollers would all be locked in the up, or fully withdrawn, position (right).
This allows rollers in the ground contact position (left) to act as rollerskate wheels, so that shallow declines can be moved down under gravity, with fixed tracks. They also allow differential motion of one track relative to another, lessening damage to both the tracks and the ground.
Rollers can also be braked, so that, in the fully down position, extra traction is provided.