Automatic steering control mechanism using sensor

Abstract

For use in an agricultural machine which is automatically steered by sensing along a row of plants, a component of the automatic steering system, namely, a comparator system is disclosed herein which utilizes hydraulic signals from independent sensors and mechanically Compares such signals with each other and with a mechanical feedback responsive to the degree of angularity of the steered wheels of the vehicle. The net result of the combination and construction of the comparator system is to provide automatic steering control for a small variation of steering of left and right steering courses, for example 2 to 5 degrees, wherein any large amount of deflection of the steering wheels that may be caused by the vehicle operator taking Over the steering function will not affect the automatic operation of the comparator mechanism or will the comparator mechanism have any response thereto? Further the hydraulic system of the comparator sensors which "feel" the presence of corn stalks or vines ahead of the vehicle is hydraulically isolated from the hydraulic circuitry of the comparator interior. The invention is susceptible for use for directory guidance by a single row of plants, for example corn stalks, or by guidance between directories, e.g., parallel rows of plants. Due to the fact that two sensors are utilized which function independently of each Other should interruption of the directory, for example, a row of corn stalks, occur due to a cross path, there would be no sudden sharp steering deflection and the vehicle would continue in straight steering.