Trimble RTK & Infill (Land Surveying)
I've run Trimble gear for nearly 10 years but have not needed to run the RTK & Infill option before. We have a small out of town topo to do in the middle of nowhere. Don't have a lot of time budgeted for the field. NGS only has vertical BMs in the area for at least 10-15 miles. No horizontal.
Want to be able to send the PC up one day, get up early the next morning, topo and get out. My understanding of RTK & Infill is that you can set up your base, do a here position, log data to the base and then topo to your hearts content with RTK, then somehow process the data. I need to make sure I can do this right and that it will work before we send him.
Who in a nutshell can tell me what I need to do to process and if I thinking right ?
We have 3 solid control point on our property. I figured this would be a good test since I have known coordinates.
I set up on one as though I've never been on site and did a hear position with the RTK & Infill style and started logging data to the base. I then started the rover, same style, and took shots on the other two control points. I'm going to log data for at least 2 hours (OPUS standard) and take at least another shot on the control.
What do I need to do once I get "back to the office"
Trimble RTK & Infill
You need to make sure that you are logging you infill data at the same rate that your base is logging static position.
If your base is logging static every three seconds, then you need to set up you infill style to collect infill shot at the same rate. So if you logging rate is 1 epic every 3 seconds then your infill topo shot will take 15seconds instead of the usual non-infill time of 5 seconds.
It has been awhile since I processed this type of data in TGO, but I do remember it was fairly easy. Just need to down load the infill data along with the DC file from the collector.
Also note that if you are going to log at 1 sec interval, remember to clear off you base memory, b/c that baby will fill up in a hurry.
Unfortunately I am using TBC now and have not had the pleasure of processing some infill data.
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Trimble RTK & Infill
I goofed around with it a couple years ago. It was like taking a knife to a gun fight. No thanks. You will be returning to the site, in spite of your lack of budget.
Like Joe said, make sure you set your logging rates the same. Your rover shots will take you longer to get everything with any level of confidence. So if you're logging at 3 seconds and want 4 epochs of data, you're at 15 seconds per shot. Thats a long time IMO for a ground shot.
You said a small site in BFE with good local control. Why not just set up a base, run it through OPUS, and shoot everything robotically. Way faster and you know you've got the data you need, plus you can review it on site before you leave.
Another option would be an ATV. Set it for 1 second, drive real slow, and you'll be done in no time. I'm sure you'll still be returning to the site, but it's always fun to ride the ATV
Wayne really does feel fortunate that I can say I still love my job!
Unless there are some rover shots that were taken when you were out of range of the base, You will not need the infill. (or I misunderstood the question)
The "here" shot is stored as a "keyed in coordinates" location. Once you get better coordinates for that location (from opus for example) you can change the coordinates in the data collector and Survey Controller will use the vectors to recalculate the location of each shot taken by the rover. I always save a copy of the job file first just in case I screw something up and I always compare before and after coordinates of 3 - 4 random points around the perimeter of the job just for peace of mind.
If you plan on twisting the job to fit the bearings of the three control points, it gets a little more complicated but it can still be done.
The part about taking a "here" shot then entering coordinates from opus later, I do that quite often.
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Trimble RTK & Infill
as long as you have the radio link you don't need to use the infill, just log data on your base, process that thru opus and manually change the coordinate for the base point. the rover data will adjust to the new base since it is the vectors from the base that are measured, not state plane coordinates. It is a very simple process, I just did this process last week in TBC. Good luck, sounds like a slam dunk.
I'm with JaRo in his response. If you've got radio link throughout the property to use OTF RTK initializations then all that is happening on the rover end is a normal RTK topo surey. At the base all the "infill" setting on the base configuration is doing is allowing the base to collect static data in a .dat file to be downloaded later.
I'm sure I lost track between 5 and 10 years ago how many thousand times I've done this. Your data epoch at the base receiver needs to be one of the multiples that works with OPUS. You also need to understand how much data your base receiver can store (in hours, not Kb) at the interval you have chosen to collect data. Otherwise, you may get the "Low Base Memory" message in the middle of your job.
If I really wanted to have additional confidence in the solutions generated by OPUS at the base, I'd do some rapid static sessions with the rover on your other control points and feed them into OPUS-RS.
If the companies that sell Trimble gear these days cannot explain how to get this all working to their customers, I need to change my focus in this career. I can explain the settings you need to modify to make this work with my eyes closed over the telephone, and your trimble dealer should be able to as well.
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Trimble RTK & Infill
I used this method for years. Make sure your survey style is set to log static data at the base. Do a here position and create a base point, I always used point 1000. Then start your rtk survey and collect data as normal. When you get to the office download the static dat file from the base and either download a couple of nearby cors stations and process on Trimble Office or send the file to opus. After your have the processed position of the base point 1000 set to control point value in TGO then hookup the data collector and download the rtk file. I haven't used this method in several years but I guess TGO is what is used to process Trimble rtk data. If done in this order your rtk points will be processed relative to the opus derived position of the base and your won't need to adjust anything. One tip is to be sure to let the base unit acquire all the svs and have a solution before you start the survey. I would expect your here position to be within 30 feet of your processed position.
Trimble RTK & Infill
by Dave Karoly, Sacramento, CA, Thursday, July 21, 2011, 20:15 (876 days ago)
TGO makes it easy.
My base receiver always logs a file; this is S.O.P. for me.
If you are tie-ing control outside of RTK radio range then just do a faststatic observation on those. Don't bother with the post-processed kinematic on those shots. By the time you drive there (won't be able to maintain lock) then get out and have to be there to initialize an Infill shot you might as well do faststatic for better results.
TGO processes everything together slicker than snot on glass.
I really miss TGO
Topcon Tools is OK but not always very intuitive.
Just like everyone else here has said, you only need to log data at your base unless something is interfering with radio communications between the base and rover.
Submit your base file to OPUS. Once you have your report back, input the control point into TGO, import your RTK .dc file, and all will be good. If you name the control point the exact same name as in your RTK file, your survey will be automatically corrected.
There is also an OPUS importer tool that is super cool. I may have it somewhere if you can't find it. It allows you to save the email as a plain text file and import it straight into TGO, just like an NGS data sheet.
Dave, if you have a copy of TGO, it works really well with RINEX files. I use it all of the time to process Leica static and PPK files. I am more familiar with it than LGO and I have found that editing bad SV data out of a baseline is easier in TGO. We have some very piss-poor "surveyors" working over here. They like to take shots under camo netting, trees, against 3 story buildings, under eaves, etc.
AS everyone has said, it is pretty easy.
If you want to email me, I can send you a document that shows you how to do this step by step.
"Make them enchiladas greasy, make them steaks chicken fried...sure does make a man feel happy to see white gravy on the side..."
Thanks All for the help and guidance.
I should mention that the "property" I was talking about in my first post was the office that I work at. My intent was to (reasonably) recreate the same known values for the control around our office. That way we could have some confidence when the crew heads out of town and avoid going back to the site.
That's where sites like this are the best..
I'm pretty sure we were thinking along the same lines in regards to processing the "infill" part of the data, but I wanted confirmation. OPUS is a good thing.
I'm a little confused on the logging interval, but I'm not really sure that needs to be a concern. If my thinking is right, I'm essentially doing 2 surveying methods at the same time and all I need to do is process them in the right order. Logging interval matching not needed.
Process with OPUS, then business as usual with the RTK side of things.