Patent ID: 11858784
Assignee: TADANO LTD.
Field: Handling (Mechanical engineering)
Classification: CPC B | IPC B

Claim 0:
1. A crane in which an actuator is controlled based on a target speed signal relating to a moving direction and a speed of a load suspended by a wire rope supported by a boom, the crane comprising:
a manipulation tool with which the speed and the moving direction of the load for the target speed signal are input; and
control circuitry including a feedback control section that is configured to compute a target course signal for the load by integrating the target speed signal and generates a first correction target course signal by subtracting a signal relating to the current position of the load from the target course signal, and a feedforward control section that is configured to adjust a weight coefficient of a transfer function representing a characteristic of the crane based on the first correction target course signal,
wherein the control circuitry is configured to
generate a second correction target course signal by correcting the first correction target course signal with the output of the feedforward control section,
compute a current position of a tip of the boom relative to the reference position based on a swivel angle of the boom, a luffing angle of the boom and an extension/retraction length of the boom,
compute a let-out amount of the wire rope based on the current position of the load and the current position of the tip of the boom,
compute a direction vector of the wire rope based on the current position of the load and a target position of the load computed based on the second correction target course signal,
compute a target position of the tip of the boom for the target position of the load based on the let-out amount of the wire rope and the direction vector of the wire rope, and
generate an operation signal for the actuator based on the target position of the tip of the boom.