Intelligent boom control with a hydraulic straight-line system for a feller buncher

An intelligent boom control hydraulic system for a feller buncher having a hoist boom and a stick boom coupled to the hoist boom, the intelligent boom control hydraulic system comprising:

• a hoist hydraulic cylinder for raising and lowering the hoist boom, the hoist hydraulic cylinder having a rod end and a base end;
• a stick hydraulic cylinder for raising and lowering the stick boom, the stick hydraulic cylinder having a rod end and base end;
• a hoist boom position sensor providing hoist boom position readings;
• a stick boom position sensor providing stick boom position readings;
• a hydraulic fluid pump;
• a hydraulic reservoir including hydraulic fluid;
• a hoist control valve controlling flow from the hydraulic pump to the base end of the hoist hydraulic cylinder, and controlling flow from the rod end of the hoist hydraulic cylinder to the hydraulic reservoir;
• a stick control valve controlling flow from the hydraulic pump to the base end of the stick hydraulic cylinder, and controlling flow from the rod end of the stick hydraulic cylinder to the hydraulic reservoir;
• a straight-line control valve for coupling the rod end of the hoist hydraulic cylinder and the rod end of the stick hydraulic cylinder;
• an operator input device for input of an operator commands;
• and
• a controller comprising a microprocessor and memory, the controller being in communication with the operator input device, the hoist boom position sensor, and the stick boom position sensor, the controller being operable to:
• determine a target hoist boom velocity and a target stick boom velocity based on the operator commands, the hoist boom position readings, and the stick boom position readings;
• access a look up chart stored in the memory, the lookup chart mapping valve combinations of the target hoist boom velocity and the target stick boom velocity to discrete valve-activation combinations corresponding to the hoist control valve, the stick control valve, and the straight-line control valve;
• and
• control the hoist control valve, the stick control valve, and the straight-line control valve in accordance with the selected valve-activation combination from the lookup chart,
• wherein the controller controls the valves such that no more than two of the hoist control valve, the stick control valve, and the straight-line control valve are simultaneously active during any operation, and
• wherein the selected valve-activation combinations move a boom tip along a substantially straight path relative to a machine frame of the feller buncher.