System Overview Introduction

The Seakeeper 16/18 uses gyroscopic principles to reduce boat roll motions in waves and wakes independent of boat speed. In multiple Seakeeper installations, the Seakeepers operate independently of each other and therefore this manual only discusses operation of a single unit.

A Seakeeper 16/18 consists of a Gyro assembly, a CAN communications cable (P/N 30243 and P/N 30301), and a Display (P/N 30298).  Figure 1 illustrates the interconnection of these components and their interface with the boat.

Figure 1 – Seakeeper 16/18 Stabilization System Components

Technical specifications provided in Section: Specifications and Summary, list the power consumption, total weight, and dimensions of the major components.  Gyroscopic principals that apply to boat roll control are discussed on Seakeeper’s web site at www.seakeeper.com. The Seakeeper website also contains videos of Seakeeper operation and videos of several different boats operating in waves with the Seakeeper on and off.  It is recommended that the reader play these videos prior to reading the remainder of this manual.

The gimbal angle and the rate of rotation about the gimbal axis (termed precession rate) play an important role in its operation.  These parameters are illustrated in Figure 2.  At zero-degree gimbal angle, the sphere is vertical; it can precess a maximum of +/- 70 degrees about this position.  The amount of torque that the Seakeeper exerts on a boat’s hull to counter the wave induced roll is directly proportional to the precession rate because the torque is exerted perpendicular to axis of the flywheel.  The farther the Seakeeper is from vertical (zero degrees) the lower the anti-roll torque.  The vertical arrows in Figure 2 illustrate the direction of the forces that the Seakeeper exerts on the boat’s hull to damp roll motion.

Figure 2 – Seakeeper Precession

Seakeeper precession is actively controlled by an electronic controller and a hydraulic brake throughout each roll cycle so the Seakeeper supplies the maximum anti-roll torque and does not make mechanical contact with hard stops that limit the maximum gimbal angle travel to +/- 70 degrees.

There is a large torque about the gimbal axis when the Seakeeper is precessing.  Seakeeper cover panels are provided to prevent personnel or equipment from contacting the Seakeeper while it is in operation.  These covers should not be stood on or have anything placed on top. The covers should always be in place during operation.  If it is ever necessary to touch the Seakeeper while the flywheel is spinning, the Seakeeper must be locked at the display to stop the Seakeeper from precessing.  Seakeeper maintenance should not be attempted unless the Seakeeper is locked and the flywheel has stopped spinning.