Switching Of Sensor And Indication; Filter Status - Furuno FMD-3200 Operator's Manual

18.6

Switching of Sensor and Indication

When a sensor cannot be used because of some problem, the system automatically
switches the sensor. When this occurs the name of the newly selected sensor appears
in yellow.
18.7

Filter Status

The ECDIS incorporates a filter that receives raw sensor data, checks sensor integrity
and processes multiple sensor data to produce a continuous estimate of ship's posi-
tion and motion.
By default, the filtering uses data from all available sensors for filtering and integrity
monitoring. The exception is heading data; only the selected heading device affects
the filter output, but other heading sensors (including magnetic compasses) are used
for integrity monitoring.
Sensors may be excluded manually or automatically. An excluded sensor participates
in neither integrity monitoring or filtering. The filter automatically excludes a sensor
from use if the sensor fails the first level of integrity check (for example, if a sudden
jump is detected). If the actual integrity check fails for some reason and the filter is able
to identify the faulty sensor, the faulty sensor is automatically excluded.
Sensor integrity is determined by: (1) monitoring the
statistical accuracy of each sensor independently
and analyzing the input values and using the informa-
tion of the type of sensor, and (2) monitoring the dif-
ference between pairs of sensors. The system
checks heading, rate of turn, position, COG/SOG and
CTW/STW data for integrity, in accordance with INS
regulations (IEC-61924-2). The result is either
[Doubtful], [Excluded], [Failed], [Not Available] or
[Passed]. The integrity check result appears in the
following locations:
• [Local Sensor Setting] and [System Sensor Set-
ting] menus. The right figure shows the result for
the heading sensor GYRO1.
• [Filter Status] page in the [Other Sensor Setting] menu. See the next page.
Doubtful (yellow): Data is not available for comparison, but data is normal.
Excluded (red): Data value changed significantly.
Failed (red): Data may or may not be available for comparison, and data is abnormal.
Speed sensor
changed
18. NAVIGATION SENSORS
LOG
BT
GYRO1
PRIM: GYRO1
Passed Passed Integrity
check
result
GYRO2
2.1° 2.1°
Passed Passed
18-9