Sensors & Software Inc. NG250 ユーザーズマニュアル
12-Survey & Map Mode
Noggin
76
When the Smart System is used in Free Run mode, it is up to the user to keep track of
positioning by some other method, for example, a measuring tape, using fiducial markers (see
Fiducial Markers on page 72) or GPS (see Section 12.3.5: P.103).
positioning by some other method, for example, a measuring tape, using fiducial markers (see
Fiducial Markers on page 72) or GPS (see Section 12.3.5: P.103).
In this mode, data collection is dependent on two factors,
1)
the speed that the Noggin system is collecting data and
2)
the speed the Noggin system is moving.
12.2.8.1 Controlling Data Collection Speed in Free Run Mode
In Free Run mode the user can control the speed the Noggin collects data by increasing or
decreasing the number of stacks (for more details on Stacking, see Stacks on page 86).
Increasing the number of Stacks has the effect of slowing down the data collection speed of the
Noggin system. Decreasing the number of Stacks has the effect of speeding up the data
collection speed Noggin system. The user can also control the speed of the Noggin data
collection by adjusting a time delay between data collection points. Note that any time delay
more than 0.0 seconds causes the system to emit a beeping sound as the data trace is collected.
decreasing the number of stacks (for more details on Stacking, see Stacks on page 86).
Increasing the number of Stacks has the effect of slowing down the data collection speed of the
Noggin system. Decreasing the number of Stacks has the effect of speeding up the data
collection speed Noggin system. The user can also control the speed of the Noggin data
collection by adjusting a time delay between data collection points. Note that any time delay
more than 0.0 seconds causes the system to emit a beeping sound as the data trace is collected.
12.2.8.2 Noggin Speed in Free Run Mode
In Free Run mode, the speed the Noggin moves determines the distance between sample points
on the ground (station interval). This type of data collection requires experimenting with the
number of stacks and time delay (see Trigger Method on page 89) and practicing to find a
satisfactory speed for the Noggin. Moving too quickly may result in under-sampling the data
making it more difficult to interpret. Moving too slowly may result in over-sampling the data. This
stretches the data image making it more difficult to interpret. As well, maintaining a uniform
speed is important for minimizing image distortion.
on the ground (station interval). This type of data collection requires experimenting with the
number of stacks and time delay (see Trigger Method on page 89) and practicing to find a
satisfactory speed for the Noggin. Moving too quickly may result in under-sampling the data
making it more difficult to interpret. Moving too slowly may result in over-sampling the data. This
stretches the data image making it more difficult to interpret. As well, maintaining a uniform
speed is important for minimizing image distortion.
12.2.8.3 Positions in Free Run Mode
Each data trace is plotted as a vertical strip on the screen (see Plot Interval on page 96). In Free
Run mode the station interval is not fixed so each screen of data can represent any ground
distance. This means that the position values displayed in Section A at the top of the data image
(see Section 12.2.3: P.71) are not correct.
Run mode the station interval is not fixed so each screen of data can represent any ground
distance. This means that the position values displayed in Section A at the top of the data image
(see Section 12.2.3: P.71) are not correct.
When running the system in Free Run mode it is best to set the units (see Position Units on page
88) to metres and the Station Interval (see Section 12.3.3.3: p.93) to a value of 1.0 metre. Then
the position values appearing on the top of the data image can be interpreted as trace numbers
and not an absolute position.
88) to metres and the Station Interval (see Section 12.3.3.3: p.93) to a value of 1.0 metre. Then
the position values appearing on the top of the data image can be interpreted as trace numbers
and not an absolute position.
12.2.9 Collecting Data using the Trigger (or B) Button
It is possible to change the triggering method from the odometer and have the Noggin system
only collect data when the Trigger button (or B button on the DVL) is pressed (see Section
12.2.9: P.76). This option is useful for collecting data when using the odometer wheel is not
practical.
only collect data when the Trigger button (or B button on the DVL) is pressed (see Section
12.2.9: P.76). This option is useful for collecting data when using the odometer wheel is not
practical.
After the user selects this option (see Trigger Method on page 89), a menu appears to select the
number of stacks for each trace. Generally, the more stacks the better the data quality (for more
details on Stacking, see Stacks on page 86).
number of stacks for each trace. Generally, the more stacks the better the data quality (for more
details on Stacking, see Stacks on page 86).