2.2 Seakeeper Assembly

The Seakeeper assembly consists of a flywheel housed in a cast aluminum vacuum-tight enclosure. The flywheel spins about a vertical axis and is supported by upper and lower pairs of bearings. A Permanent Magnet AC motor mounted inside the enclosure spins the flywheel at high speed.

The enclosure is fastened to two gimbal shafts that are supported by gimbal bearings on either side. These shafts establish an athwartship gimbal axis about which the flywheel and enclosure precess or rotate up to +/- 60 degrees during operation. The gimbal bearings are supported by a foundation which is attached to the hull structure. This foundation transfers the loads that the Seakeeper produces to the hull structure.

An active hydraulic brake mechanism is located on the Seakeeper assembly to regulate the Seakeeper’s precession motions about the gimbal shaft. It includes four hydraulic cylinders and a hydraulic manifold.

A coolant pump, heat exchanger with reservoir, and thermostat are located near the manifold. A glycol/water mix is circulated through a closed loop to the motor drive box, hydraulic manifold, and the water jackets of the flywheel enclosure to remove heat.

Figure 3 – Seakeeper Assembly