Development of an Active Mass Damper for Stabilizing the Load Suspended on a Floating Crane

Abstract

To minimize the necessity to suspend shackling work floating crane on account of vessel rolling, an active mass damper system was developed to attenuate oscillation of the sling frame under which the shackles are suspended. The motion of actual floating crane under sea wave was measured to determine the mechanism of sling frame oscillation, and to verify from theoretical analysis the effectiveness of installing an active mass damper on the sling frame. For further ascertaining damper performance, a 1/40 size model of the crane barge mounted with the damper was tested in tank, which indicated reduction to 1/3 – 1/2 of sling frame oscillation, with good agreement between the theoretically estimated and measured results. Test at sea on actual floating crane equipped with active mass damper system confirmed that actuation of the system would reduce to roughly 1/2 the oscillation of sling frame.

Dynamics and Control of Cranes: A Review

“…However, in some filter designs, suppression of the subcritical bifurcation produced a large resonance-like response around half the natural frequency. Iwasaki et al (1997) and Imazeki et al (1998) designed an active mass-damper system to suppress payload pendulations. The system was installed on the sling of a barge-mounted boom crane.…”

Payload Pendulation Reduction Using a Variable-Geometry-Truss Architecture with LQR and Fuzzy Controls

“…Among the proposed schemes, Chin and Nayfeh (1996), Chin et al (2000), and Abdel- Rahman and Nayfeh (2000) explored the reeling/unreeling of the cable to suppress some of the bifurcations leading to large and complex responses (coupled in-plane and out-of-plane modes). Iwasaki et al (1997) and Imazeki et al (1998) designed an active mass-damper system and installed it on the sling of a barge-mounted boom crane. Lacarbonara et al (2000) designed a fully passive spring-mass double-pendulum system to reduce payload pendulations and showed that it possessed broad-band vibration absorption characteristics.…”