Ishikawajima-Harima Heavy Industries Co., Ltd. (IHI) has developed a new type of anti-rolling device for ships and the first production model with a 100 t moving mass was delivered for an oceanographic research vessel "MIRAI" (8,672 GT).
What is "Hybrid"?
"Hybrid" means combination of the advantages of both passive and active mechanisms.
(1) Passive mechanism：
The moving mass on arc-shaped rails traverses like the swing of the pendulum.
(2) Active mechanism：
Oscillating speed of the mass is adjusted by computer-controlled electric motors by real time sensing of ship rolling to achieve optimum damping effect.
Performance of rolling reduction the moving mass weight equivalent to about 1.0-1.5% of ship's displacement will be required to reduce rolling angle by half.
Excellent features of the new system
(1) Compact and high performance anti-rolling system ever developed
(2) Effective in various ship speeds, full navigation, slow speed, drifting
(3) Sensitive response against various wave conditions
(4) Widely applicable in change of ship's loading condition
