B62D 11/16

Steering non-deflectable wheels; Steering endless tracks or the like by differentially driving ground-engaging elements on opposite vehicle sides by means of a single main power source using gearings with differential power outputs on opposite sides, e.g. with twin-differential or epicyclic gears differential power outputs being effected by additional power supply to one side, e.g. power originating from secondary power source the additional power supply being supplied mechanically