A HUMAN NECESSITIES
A01 AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
A01B SOIL WORKING IN AGRICULTURE OR FORESTRY; PARTS, DETAILS, OR ACCESSORIES OF AGRICULTURAL MACHINES OR IMPLEMENTS, IN GENERAL
69/00 Steering of agricultural machines or implements; Guiding agricultural machines or implements on a desired track
A01B69/007 Steering or guiding of agricultural vehicles, e.g. steering of the tractor to keep the plough in the furrow