| 摘要 |
A method for reducing resonant vibrations and dynamic loads of cranes (1), whose horizontal and vertical motion of the pay load (38) are controlled by a boom winch (24) controlling the luffing motion of a pivoting boom (16) and a hoist winch (36) controlling the vertical distance between a boom tip (30) and the load (38), and where the method includes the steps of: - determining the resonance frequencies of the coupled crane boom (16) and load (38) system, either experimentally or theoretically at least from data on inertia of the boom (16) and stiffness of at least a boom rope (18), a hoist rope (26), a pedestal (6) and an A-frame (19); - automatic generation of a damping motion in at least one of said winches (24, 36), that counteract dynamic oscillations in the crane (1); and - adding this damping motion to the motion determined by a crane operator. |
