FastStatic Setup Guide
The following is a concise step-by-step guide to setting up the Trimble
equipment for FastStatic surveying. It does not cover the theory of
operation; these instructions are much more useful after an
introduction to the system.
Base Station Setup - do this first
- GPS Receiver
- Setup GPS antenna tripod and tribrach; insure that the optical
plummet is aligned with the base station benchmark, and that the
tribrach is level.
- Attach GPS satellite antenna ("GPS antenna") to the tribrach via
the brass adapter. Attach GPS antenna cable (yellow 3-shell [large] Lemo
co-ax to right-angle coaxial connector) to the antenna.
- Connect the base station battery (use the attached cable) to port
#2 or #3 of the GPS receiver.
- Connect the GPS antenna cable to the receiver's antenna port
(labelled, and the only port that fits).
- Connect the data collector I/O cable to receiver port #1; the cable
is black, with 0-shell [small] Lemo connectors on each end. One end is
straight, the other a right-angle. Connect the right angle connector
to the receiver.
- Place the receiver inside the transport case (for weatherproofing).
Be sure not the have any sharp bends in the cables, and do not clamp
the lid on any cables.
- Connect the data collector to the other end of the data collector
I/O cable connected to receiver port #1.
- Turn on the data collector and GPS receiver by pressing the green
power button on the data collector.
- Measure the GPS antenna height using the Height Rod. Measure at
3 points (120 degrees apart). Always measure from the benchmark
stamp to the bottom edge of the groundplane, inside a notch. Record
the three measurements; if they are different by more than a few mm,
check level and centering of the GPS antenna. Average the readings
and enter the average into the data collector when prompted; either
enter in meters, or type in the number followed by the unit (e.g. cm
for centimeters). Check that the measurement type is set correctly.
- Start the base station measurements
- Make sure that the correct Job is selected on the data collector.
New Jobs may be defined in the Files mode.
- On the hand controller, choose Survey, and then choose
the appropriate Survey Style; typically Trimble FastStatic or a
custom style. New styles may be defined at this stage, or in the
Survey Styles option in the Configuration mode.
- Choose Start base station. Type in the benchmark name,
and the antenna height. If the station is not in the hand controller
already, there will be a warning about no coordinates; ignore the
warning.
- Press the measure softkey, and disconnect the
data collector when instructed to do so. Do not turn off the
base receiver. Check that the satellite LED (red) is
blinking slowly, and the storage light (yellow) is on. This indicates
everything is working correctly.
Rover setup - do this after the base station is running
- GPS receiver
- Place 2 charged camcorder batteries in the holders at the bottom
of the rover backpack.
- Connect the battery cables to the batteries, and use the Velcro
straps to secure the batteries and cables in place.
- Strap receiver into the backpack, upside down. Use the lower set
of straps, which have 2 black foam pads underneath.
- Connect the battery cables to ports #2 & #3 on the GPS
receiver.
- Attach the GPS antenna cable to the receiver. Connect the 3-shell
Lemo [large] to the GPS receiver, and leave the right-angle co-axial
connector free. Coil most of the antenna cable neatly above the
receiver, and strap it down with the velcro straps.
- Leave ~10 feet free of the straps, and neatly coil it in the
backpack; this will be used to connect to the antenna on the tripod.
- Connect the data collector I/O cable to receiver port #1.
- Thread the data collector I/O cable through the lower
pass-through on the same side as the GPS antenna cable. Connect to
the data collector.
- Tie down loose cables in the pack, and zip it closed.
- Start the rover measurements
- Setup GPS antenna tripod and tribrach; insure that the optical
plummet is aligned with the base station benchmark, and that the
tribrach is level.
- Attach GPS satellite antenna ("GPS antenna") to the tribrach via
the brass adapter. Attach free end of the GPS antenna cable to the antenna.
Be careful not to kink the antenna cable by pulling it out of the
pack; unzip the pack and extract the coil, uncoil it, and then zip
the pack closed.
- Turn on the data collector (and hence the GPS receiver).
- Measure the GPS antenna height using the Height Rod. Measure at
3 points (120 degrees apart). Always measure from the benchmark
stamp to the bottom edge of the groundplane, inside a notch. Record
the three measurements; if they are different by more than a few mm,
check level and centering of the GPS antenna. Average the readings
and enter the average into the data collector when prompted; either
enter in meters, or type in the number followed by the unit (e.g. cm
for centimeters). Check that the measurement type is set correctly.
- Make sure that the correct Job is selected on the data collector.
New Jobs may be defined in the Files mode.
- On the hand controller, choose Survey, and then choose
the appropriate Survey Style; typically Trimble FastStatic or a
custom style. New styles may be defined at this stage, or in the
Survey Styles option in the Configuration mode. Be
sure to choose the same style as for the base station.
- Choose Start survey. [This step is optional]
- Choose Measure Points.
- Type in the benchmark name, and antenna height.
- Press the Measure softkey.
- Wait for sufficient data to be collected; this will take between
30 and 120 minutes.
- While data is being collected, keep the screen of the hand
controller out of direct sunlight. It is generally wisest to place
the controller back into the pack, with the cable sticking out the
top.
- Do not automatically store data when "enough" time has elapsed;
more data is always better.
- Press the Store softkey.
- Press ESC and choose End Survey
- Turn off the receiver from the hand controller.
- Disconnect the antenna cable and recoil in the pack.
- Remove the tribrach adapter from the antenna, and put the
tribrach into the transport case.
- Pack up the backpack (w/controller), antenna, tribrach, and
tripod, and move to the next site.
- For all GPS surveying, try to keep the PDOP < 6.0 - the best
yet seen was 1.7 (8 satellites in open terrain), and PDOP tends to
average about 3.0 with 5 or more satellites.
Written by Paul Gettings
Last modified Thursday, 19-Feb-2004 13:49:23 MST