Kongsberg Seapath 320, Technical Manual

Page: 11 / 100

Technical Description
Man_techn_seapath320/rev.1 XI
Terminology
Alignment Is the process of adjusting the current internal navigation frame in
the instrument to the true external frame.
Antenna bracket Is the arrangement for mounting the GPS antennas.
Antenna holder Is the arrangement on board the vessel for mounting the antenna
bracket to.
Attitude The orientation relative to the vertical axis of a vehicle. Heading is
not included. If heading is included the word "orientation" is used
for the vehicle.
Beam The maximum width of the vessel at Main Deck level (B. mld).
GPS Time The time in the GPS system. The GPS time is within UTC time
±180 nsec (95 per cent) plus leap second.
Heading The direction of the main axis (bow direction) of the vehicle as
opposed to course, which is the direction of motion of the vehicle.
Yaw angle as defined here is the same as heading.
Heave The vertical dynamic motion of a vehicle and defined positive
down. Heave position and velocity are dynamic motion variables
oscillating around a mean value, typically zero.
Height The height in the Seapath product is defined as the vertical position
relative to the WGS84 datum (rotational ellipsoid).
Host system In this manual defined as Navigation computers, Dynamic
Positioning Systems, etc., receiving data from Seapath.
Origin The zero point in the coordinate system. The origin is the
intersection point between AP, BL and CL.
P-axis This axis is fixed in the vehicle, and points in the starboard
direction horizontally when the roll angle is zero. Positive rotation
about this axis is bow of the vehicle up.
Pitch A rotation about the pitch axis is positive when the bow moves up.
Normally, pitch means the dynamic pitch angle motions.
R-axis This axis is fixed in the vehicle, and points in the forward direction
horizontally when the pitch angle is zero. Positive rotation about
this axis is starboard side of the vehicle down.
Roll A rotation about the roll axis is positive when starboard side of the
vehicle moves down. Normally, roll means the dynamic roll angle
motion.
Starboard When looking in the bow direction of a vehicle, this is the right
hand side of the vehicle.