Patent ID: 8915308

Claim:
An apparatus for controlling in a closed loop the height of a front mounted blade on earth moving equipment, comprising: said front mounted blade forming an aggregate with a pair of supporting arms connected to a body of the earth moving equipment at pivot points and rotated in planes perpendicular to a connecting line between said pivot points by means of hydraulic cylinders supplied via valves; said front mounted blade carrying at least one absolute height sensor in the closed loop; said aggregate carrying one inertial sensor in the closed loop; outputs of said absolute height sensor and single inertial sensor being combined in a calculating unit, the outputs being devoid of body angle or body rotation of the body of the earth moving equipment; output of said calculating unit and a set height being compared in a comparator, the comparator being in the controlled loop; output of said comparator providing the input for a regulator for controlling said valves; and wherein said one inertial sensor has a single degree of freedom, the output of which is angular velocity in a plane perpendicular to the connecting line between said pivot points, which for use in said calculating unit is converted to angular increment of said supporting arms in said plane.