Kongsberg SBP 29, Installation Manual

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Measurement of the transducer orientation
The heading of the transducers is measured as the average heading of the two fore-and-aft
oriented sides of each transducer in the horizontal plane of the vessel coordinate system.
Thus, the heading of the transmit transducer is the heading of the long sides, while the
heading of the receiver array is the heading of the short sides. As the latter may be
difficult to measure accurately, it may be better to measure the heading of the long sides,
and then subtract 90° to achieve the correct value.
Roll and pitch measurements are made according to standard conventions with
positivepitch angle if the transmitter array’s forward end is above the aft end (tilts up),
andpositive roll if the starboard side of the receiver array is lower than the port side.
The actual measurement of the installation angles may be done by two different methods.
• The most accurate method is to use land surveying techniques, establish a horizontal
plane and do distance measurements to and in this plane.
• The second method is to use an inclinometer to measure roll and pitch angles
combined with the distance measurements in the horizontal plane for heading. This
method is simpler, but will require a sufficiently accurate inclinometer.
Note that it may be most practical to perform these measurements on the transducer
mounting frames before installation of the transducer modules. This is an acceptable
method.
Mounting frames and structures
No actual measurements of the orientation or location of the transducer mounting
structures are required. However, the mounting structures must not deviate from a flat
surface by more than 2.5 mm This can be checked by placing a ruler along the long side
of the transducer array, and check the opening between the side and the ruler.
Dimensional surveying and alignment