US Patent 7040552 Suspended boom with gauge members

An applicator boom apparatus comprises an applicator boom extending laterally from a vehicle, and pivotally attached to the vehicle such that the boom can pivot up and down with respect to the vehicle. A kit provides a gauge member adapted to ride along a surface of the ground and support an outer portion of the boom such that the boom moves up and down with the gauge member as the gauge member rides along the ground, and also provides an active hydraulic source powering the shoulder hydraulic cylinder of the apparatus such that the shoulder hydraulic cylinder exerts an upward force on the boom such that a downward force exerted on the gauge member by the boom is reduced.