Abstract: A centerline sight apparatus includes a housing mounted on the forward end of a tractor with a sight arm operably mounted in the housing for transverse movement with respect to the longitudinal axis of the tractor. A second sight arm is operably mounted below the first sight arm and moves parallel to the first sight arm at a speed approximately twice as fast and in the same direction as the first sight arm. Both sight arms are connected to a motor which is responsive to movement of a pendulum, so as to move the sight arms in one direction of the other. The pendulum is mounted to sense the lateral cant of the tractor with respect to the tractor's longitudinal axis.

Abstract: A centerline sight device is mounted on a tractor to enable the driver to automatically steer the tractor along a center row or longitudinal mark to align the tractor with respect to furrows of crops in a field. The sight device includes a slight arm housing mounted on the forward end of the tractor, with a sight arm operably mounted on the housing to move transversely with respect to the longitudinal axis of the tractor. A motor is mounted on the sight arm housing to move the sight arm in response to selective activation by the tractor driver. A lamp assembly housing is mounted on the tractor forwardly of the seat and rearwardly of the sight arm, and has a plurality of lamps spaced transversely across the top perpendicular to the longitudinal axis of the tractor. The lamps are electrically connected to the motor and sight arm so as to light a particular lamp in response to the position of the sight arm.

Abstract: A tractor guidance apparatus includes a laterally adjustable sight equipped with a reverse pendulum whereby an upright pivotal sight needle is moved in the same transverse direction as the depending pendulum in response to pivotal movement of the pendulum.

Abstract: A vision correction device for enabling a tractor to be maintained in centered relation over a guide furrow or the like includes a sighting device and a mounting strip for supporting the sighting device on a tractor forwardly of the operator seat and with freedom of transverse movement relative to the longitudinal center line of the tractor. A lock mechanism is provided for securing the sighting device in a selected transverse position whereby upon adjusting the sighting device to intersect a line of sight from the dominant eye of an operator on the operator seat to a ground furrow situated forwardly and centrally of the tractor, the tractor may be maintained in centered relation over the ground furrow by steering the tractor to maintain the sighting device in alignment with the ground furrow.