RTK GPS Survey
... Abridged version of notes from the RTK class.
- Set up Bluetooth communication with the GPS: General Survey -> Instruments -> GNSS functions -> Bluetooth
- identify both the rover and the base GPS here.
- Set the Survey Style: Main Menu -> Settings -> Survey Styles
- rtk int radio = internal radios on both gps
- RTK = use an external radio for the base.
to be continued...
2013 September Update
For visiting a new site and executing a gps survey:
- Pound a rebar into the ground to use as a ground control point
- Set Tripod up over Rebar.
- Mount the Tribarach to the tripod
- Screw the base GPS into a 6" range pole extension, and mount to the hockey puck on the tribarach
- screw the antenna on to the base gps
- connect the base station battery to the gps
- Measure from the Middle of the blue rubber bumper on the base gps to the ground control point.
- Mount the Rover GPS to the Range Pole
- Connect the rover battery and antenna
- The all thread center of the rangepole is extendable. Raise it until the blue rubber bumper on the rover GPS is at 1.55 meters. There is a brass knurled nut that can be spun into place to prevent movement of the all thread center.
- Mount the TSC3 handheld controller to the rover GPS range pole.
- Turn on the TSC3. From the Trimble Software select General Survey
- Next, Select Jobs; New Job
- This will bring up a new window. The coordinate system will need to be selected.
- Side note: If you want to use like the 2009 GEOID it is easiest to set that up using the Trimble Business Center on the toughbook, import this job as noted lower in this page. I think that might be generally the best practice: Set up the job before visiting the survey site actually. Anyway, if you aren't doing it that way...
- Select the Coordinate System
- Select it from the Library:
- System: UTM
- Zone: 7 = Barrow; 6 = Prudhoe... check your handheld GPS if you're not sure what zone you're in.
- Datum: NAD1983 Alaska
- Project Height: 100
- Now the job is setup. With the Rover and Base GPS both turned on:
- Click on the Measure Button
- Click rtk int radio...
- Click Start Base Receiver
- For a site you've never visited before, once you start the base receiver it will prompt you for a point name.
- Select Key In
- Select Here
- Name the point
- Enter Antenna Height, a quantity you measured earlier in the setup process
- Measured to: Center of bumper
- Click Start
- Now we'll start the rover. Again, click Measure then Measure Points
- The handheld will try to establish a link to the rover GPS.
- You will be prompted for the base gps you wish to connect to. Index 27 is ours.
- Now you're nearly ready to survey. First though the Rover GPS parameters will need to be entered.
- Set the Antenna Height to 1.55 meters
- Measured to: Center of Bumper
- Click the Options button at the bottom of the screen
- Change the number of measurements from 20 to 5
- You're now ready to survey.
2013 April Update
Trimble 2009 Geoid http://www.trimble.com/support_trl.asp?pt=&Nav=Collection-66364
Connecting to the Barrow RTK System:
- http://baid.utep.edu/dgps-support ...there is a pdf on here available for download.
http://facility.unavco.org/project_support/polar/barrow/equip.html I have added a new base radio & configuration to the
Following existing points is called 'Stakeout'
So, maybe the TDL450 radio can't tie in to the barrow network, which seems to operate at 418 MHz (which makes sense since we need to receive data not transmit it): http://facility.unavco.org/project_support/polar/barrow/equip.html //In addition, the base station transmits real-time kinematic (RTK) broadcasts at 418 MHz (CMR+ format at 9600 baud). //
Handy document showing how to change the receive frequencies for the R8 so that it can receive Toolik and Barrow freqs:
http://cody.inlandgps.com/pub/Trimble%20Stuff/Instructions%20by%20Inland%20GPS/Installing%20Receive%20Frequencies.pdf
Here is the firmware for reflashing: http://www.trimble.com/trimbler8gnss_ts.asp?Nav=Collection-21462
So, how to get this all going for doing stakeouts:
- Start Trimble Business Center
- Set the Projection information for the project
- File Menu -> Import -> CSV
- Select All of the points (CTRL-A)
- File Menu -> Export
- Select 'Trimble Field Software exporter (jobXML)
- Click Export Button and save
- Copy the resulting file onto the TSC3
- From the TSC3 Start a General Survey
- Click on Job
- Click on Import / Export
- Click on Import Fixed Format Files
- File Format: Trimble Job XML
- Navigate to & import the file.
- Now, back at the General Survey Menu
- Click on Job
- Click on Open Job
- Navigate to and select the recently imported job.
- Now , back at the General Survey Menu
- Click on Stakeout
- Click on the communication path