Patent ID: 7588089

Claim:
A method for controlling a ground-engaging implement coupled to an agricultural tractor, the method comprising the steps of: providing a ground-supported agricultural tractor having a three-point hitch movable in upward and downward directions by at least one hydraulic actuating cylinder; providing a ground-engaging implement attached to the hitch of the tractor; providing a hitch control apparatus for managing the upward/downward position of the hitch to maintain a desired draft load or position on the tractor, the hitch control apparatus having programming implementing theory and equations to derive implement weight and center of gravity location; providing an actuating cylinder pressure sensor for measuring hydraulic pressure in the actuating cylinder and communicating a pressure value to the hitch control apparatus; providing a hitch position sensor for measuring upward/downward position of the hitch and communicating a position value to the hitch control apparatus; positioning the implement in a first position with no portion of its weight supported by the ground; generating a first pressure value by the actuating cylinder pressure sensor; generating a first position value by the hitch position sensor; communicating the first pressure value and the first position value to the hitch control apparatus; positioning the implement in a second position; generating a second pressure value by the actuating cylinder pressure sensor; generating a second position value by the hitch position sensor; communicating the second pressure value and the second position value to the hitch control apparatus; and deriving from the first and second pressure and position values of the hitch, in accordance with the programming of the hitch control apparatus, an implement weight and a location of an implement center of gravity by the hitch control apparatus; wherein said center of gravity of said implement is derived from the ratio of said first and second generated pressure values.