Abstract:
Pedestal motion compensation device 1) for compensating heave, pitch and roll motion of a carrier frame on board of a vessel. The device comprises: a carrier frame (2); a base (3) for supporting the device on the vessel; a z-translation unit (4); and a xy-rotation unit (5). The z-translation unit allows a z-axis translational movement. The xy-rotation unit allows x-axis rotational movement as well as y-axis rotational movement. A z-axis rotational movement is prevented by a linear guide system (12), and a main universal joint (14) including a blocking element (58), so that the carrier frame and the base are moveable with respect to each other in a translational direction along the z-axis, in a rotational direction around the x-axis and in a rotational direction around the y-axis but restrained from mutual movement in a translational direction along the x-axis, in a translational direction along the y-axis and in a rotational direction around the z-axis.
Abstract:
The invention concerns a method for transferring a load between a target position on board a vessel (40) and an outboard position outboard said vessel. The invention further concerns a motion compensation device (1) applying the method. In the method the load is being transferred by a crane (30) carried by a motion compensation device arranged on board the vessel. The motion compensation device comprises a carrier frame (2), a base (3) and an actuator system (8, 9)for moving the carrier frame with respect to the base; the base being fixed to the vessel and the crane being carried by the carrier frame. During picking up a load from the vessel or placing a load on the vessel, the actuator system is being driven in an on board mode such that the carrier frame is being compensated for x-axis rotational movement and y-axis rotational movement of the vessel, and follows, viewed in the vertical direction, the vertical movement of the target location. During picking up a load from the outboard position or placing a load on the outboard position, the actuator system is being driven in an outboard mode such that the carrier frame is being compensated for x-axis rotational movement, y-axis rotational movement and z-axis translational movement of the vessel.