Depth; Dvl And Usbl Combined Systems; Heave; Temperature - Advanced Navigation Spatial OEM Reference Manual

Illustration 27: Spatial USBL Setup
7.12.3

Depth

For Spatial's intelligent filter to operate correctly and provide maximum performance, Spatial
requires continuous updates of depth information. This can be achieved by adding a pressure
depth transducer to Spatial. Spatial supports frequency output pressure depth transducers using
the GPIO pins, please see section 8.3.26. Alternatively if depth is already known, it can be fed into
Spatial using the External Depth Packet. Some Teledyne DVLs feature a built in pressure sensor,
in this case Spatial will automatically use the DVL pressure to determine depth.
7.12.4

DVL and USBL Combined Systems

For systems that require the highest accuracy, Spatial can be combined with both a DVL and
USBL. By using both the DVL velocity and USBL position, Spatial is able to provide very accurate
underwater navigation.
7.13

Heave

Spatial can provide vertical heave position at four different points on a ship. Spatial's heave filter is
always on and fully automatic. After power on, Spatial requires approximately 5 minutes for it's
heave filter to converge upon an accurate solution. Heave works without a GNSS fix, however best
heave performance is achieved when Spatial has a GNSS fix.
By default Spatial provides heave from the point at which the Spatial unit is mounted, however it
can provide heave at four different offset points on the ship. To set the heave offsets, either use the
heave configuration dialog in Spatial Manager or the Heave Offset Packet.
7.14

Temperature

Spatial should not be subjected to temperature's outside of it's operating range. If the temperature
rises above 90 degrees Celsius, Spatial will automatically shut off power to it's sensors and GNSS
in an attempt to prevent damage, this will also send the filters into reset. Subjecting Spatial to
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