I'm 15 years out of date on setting up at base station/rover configuration. Looking for current workflow/best practices for setting up a RTK project.
Back then, using Trimble equipment, my steps were:
Set up base station and collect static observations for extended period of time. (Often I had plenty of time, so observed for 12-24 hours.)
Submit observations to OPUS.
With OPUS derived results for base station location, calibrate the job to surrounding control points.
Go to work.
Planning to use Trimble equipment.
Suggestions on different or better?
I picked up a big project in eastern Washington where robotic won't be efficient. For example, first task is layout of 10 miles of silt fence.
Lots has changed. Trimble has some sort of office suite, where things are "brought together". I forget it's name.
Others discuss it here. I'm using another brand. But, I'd suggest go work a couple of days with someone with modern Trimble gear. Even one day field and one day office will help a lot.
Thanks,
N
Ps, here's a thread about it:
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Are You using 15 yo Trimble gear?
@jitterboogie No - rent to start. Since all my robotic gear is Trimble with Access software, want to stick with that.
Sure thing.?ÿ If you rent, get a VRS set up.?ÿ Then the static stuff id just in case you end up with bad cell signal or if your VRS is wonky.
If you can't do VRS, see what a repeater set up would cost because you can cover a HUGE area depending on how your project layout is unfolded.
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You can PM me if you want to talk about it.?ÿ I have time to kill because i don't want to study, and would be happy to blame anyone else for me not grinding that stone.
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I'd probably be doing things just as you say, and bringing the vectors into StarNet. If you work in state plane or some other grid system you can dispense with the calibration business.?ÿ
An option would be to sign up for the VRS and go without a base station (that is, one that you control). But the work flow is basically the same as ever.?ÿ ?ÿ
15yrs ago you probably didn't have the benefit of GLONASS ,et al. With those constellations you will find that the performance of RTK has dramatically improved. Positions - good positions - in places you couldn't get a fix before.
Tim,?ÿ Mark is spot on with the WSRN if you have cell service throughout the project are.?ÿ Since you are on the construction end, I'm guessing you don't have much say in the coordinate system you will be using so you will still need to do some type of site calibration.?ÿ As for the constellations, why stop at GLONASS, I would add on Galileo at least.
Geography will drive your solution. VRS has gotten great in many areas, but we have vast areas where VRS is either non-existent or unreliable. Base/rover is the best solution there. Have the base gather static so you can grab static on faraway points if the radio drops off. The best solution is to be ready for VRS, Base/Rover or static all the time.?ÿ
I would second the comment to use a predetermined projection rather than calibrate. I can count the last ten years worth of calibrations on one hand. They have thier place but not as a go-to work flow...
Using existing control with good metadata:
Set up the DC file as it is given, occupy a control point with the RTK base using those numbers, RTK survey and check other control points, they should check well, do no adjustments if they check within your tolerances.
Do not calibrate. RTK survey and collect static at the base and any other point you wish for later processing.?ÿ
If the control doesn't have metadata or doesn't check with the given metadata then a calibration might be necessary; frankly if the control is properly laid out calibration isn't necessary except it might save a small amount of time.?ÿ
If you do need to calibrate use static data to do it, you will not regret that decision. And do it in a second file, keep a "clean" one with the days vectors and data.?ÿ
A Trimble TBC file that's calibrated will show two sets of LAT, LONGS one will be real LAT, LONGS (Global), the other will be not be (Local), they will be calibrated numbers so be careful of them. I would never give them out for any reason.?ÿ
Yes, I stopped using RTK right around the time GLONASS was an option.
I'm skeptical of using VRS. I visited the site 10 days ago and had limited cell phone reception.
"All dimensions, elevations, and stations are in US Survey fee, unless indicated otherwise.
All Horizontal and Vertical coordinates are shown in the Washington State Plane Coordinate System of 1983 (NAD 83) and 1988 (VAVD 88), South Zone"
Conveniently, all the structural work is oriented N-S, E-W on this 1600 acre site.
Calibrate with static sessions was my procedure back in those days, but thanks for that reminder. Same for separate/clean file.
Why would that be? Make metadata a contract requirement. Key in parameters, check in and go to work.
If cell service is not real good, and I mean full bars always and everywhere,?ÿ (as 10 miles of silt fence in eastern Washington suggested might be the case) then VRS isn't for you.
9.60 miles of silt fence...?ÿ follow by 9.63 miles of perimeter security fence.
Since it's all state plane, it shouldn't need calibration.?ÿ
There was a big push for calibration back in the day which was mostly used to control vertical. The Geoid models were very inaccurate and calibration was a way to get closer to elevations. Problem was it didn't work very well. The new Geoid models are much better and if you're "calibrating" .02' horizontally in some control it's simply better to note the "misclosure" and move on.?ÿ
Thanks to all for the replies. I now have a game plan...
Nah, but I've spent tons of time in the Gorge and the area when My Brother lived in Walla Walla, and got married in Hood River.
I'm guessing its a new data center or a vineyard that's expanding.?ÿ I'd love to move that way but my sig other hates clouds.?ÿ I'm from the midwest originally so miss them a lot.
