Method for controlling power-transmission gear, system, and forest machine

A method for controlling a power-transmission gear in a forest machine comprising a harvester head, the method comprising:

• measuring a selected property of at least first and second trees with aid of observation means using electromagnetic radiation at a distance from the at least first and second trees to create measurement data for the at least first and second trees;
• storing the measurement data of the at least first and second trees in a register of the trees' measurement data belonging to a memory for controlling the power-transmission gear;
• controlling the power-transmission gear with aid of software means, on a basis of the measurement data of the first tree, to create a change in a state of the power-transmission gear before the harvester head contacts the first tree so that the power-transmission gear transfers to a first operating device belonging to the forest machine an amount of energy optimized on the basis of the measurement data in terms of performing a selected operation;
• performing the selected operation of the first operating device using the amount of energy transferred by the power-transmission gear after the change in state of the power-transmission gear, in which the operation of the first operating device creates a change in the attitude, location, or state of the harvester head, or a combination of the aforesaid;
• controlling the power-transmission gear at the second tree in the register on a basis of the measurement data of the second tree in the register;
• and
• repeating the foregoing steps on subsequent trees, wherein the second tree becomes a new first tree and a tree subsequent to the second tree becomes a new second tree for performing the foregoing steps.

A system for controlling a power-transmission gear in a forest machine, which forest machine includes a chassis, a harvester head for processing trees, a crane pivoted to the chassis for suspending the harvester head, a first operating device for creating a change in the harvester head's attitude, location, or state, and a power-transmission gear for transmitting energy to a first operating device, the system including:

• observation means for detecting electromagnetic radiation and measuring a selected property of at least first and second trees on a basis of the electromagnetic radiation at a distance from the trees being measured, to create measurement data;
• and
• software means arranged to:
• record the measurement data of the observation means in a memory to create a register,
• control the power-transmission gear on a basis of the measurement data of at least the first tree to create a change of state in the power-transmission gear before the harvester head contacts the first tree thus permitting sufficient energy to be sent to the first operating device to optimize and perform an operation of the first operating device,
• control the power-transmission gear at the second tree in the register on basis of the measurement data of the second tree before the harvester head contacts the second tree in the register, and
• repeat the operations of the observation means and the software means on trees subsequent to the second tree, wherein the second tree becomes a new first tree and a tree subsequent to the second tree becomes a new second tree on which the observation means and software mean operate.