Crane

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 that is configured to generate an operation signal for the actuator based on the target speed signal;
• wherein the control circuitry is configured to
• compute a target course signal by integrating the target speed signal input from the manipulation tool and attenuating a frequency component in a predetermined frequency range via a filter expressed by Expression 1,
• compute a target position of the load relative to the reference position based on the target course signal,
• compute a current position of a boom tip 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 boom tip,
• compute a direction vector of the wire rope based on the current position of the load and the target position of the load,
• compute a target position of the boom tip 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 boom tip,
• (
• Expression
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• =
• a
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• where each of a and b is a coefficient, c is an index and s is a differentiation element.