Continuous Kinematic; Stop&Go Kinematic - ashtech Z-Xtreme System Manual

level positions. If you are walking around the project site, a position is calculated
every 2 seconds producing a crumb-trail of where you walked. If you stop and
observe a feature of interest for 10 seconds, five data samples are observed for this
feature, producing a more precise position than those produced while walking. The
ability to determine positions while observing a feature for a period of time and the
ability to determine positions while moving around the project site results in two
modes of positioning features of interest with the rover system. These two modes are
termed Continuous Kinematic and Stop&Go Kinematic.

Continuous Kinematic

The Continuous Kinematic mode of data collection is best used when positioning lin-
ear features such as roads. The idea is to trace the feature to be positioned. As you
are walking along this feature, positions are being determined at a specified interval,
delineating the feature. Here is an example where this would be useful:
You have an as-built survey which includes a road approximately 100 feet in
length. You need to position the centerline of the road and the edge of pave-
ment on both sides. You walk out to the centerline with the rover system.
Using the handheld software, you instruct the system to determine a position
every 2 seconds (a point ID is generated automatically every 2 seconds). You
then walk along the centerline from beginning to end. When this data is pro-
cessed, you will see the centerline of the road delineated with a position every
2 seconds for the time period which you were walking along the centerline.
The Continuous Kinematic method is not as precise as the Stop&Go Kine-
matic method since, with Continous Kinematic, each position is determined
with only one data sample, while with Stop&Go Kinematic, multiple data sam-
ples are combined to produce a position. With Continuous Kinematic, you
can expect positions at the 0.03 – 0.05 meter (0.10 – 0.15 ft) level.
Stop&Go Kinematic
The Stop&Go Kinematic mode of data collection is best used when positioning point
features. It can also be used to position linear features by collecting multiple points to
delineate the feature. Here is an example of how the method works:
In the same as-built survey, you have a number of point features to locate, such
as light poles and manhole covers. You position the rover pole over the point
feature to be located. Using the handheld software, you instruct the system to
collect 8 seconds of data at this location. The handheld software will assign the
same point ID to each data sample collected. When this data is processed, all
data samples collected at this location will be used to compute one position for
the point feature.
The Stop&Go Kinematic method is more precise than the Continuous Kinematic
method since multiple data samples are used to compute one position for a point fea-
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