I am a new septic designer trying to start my own business. I am basically trying to figure out if all my needs can be met with a pair of RS2+ receivers (even better if I could do it with just 1), or if I would need a total station as well.
I have two basic functions I need to achieve.
Setting the permanent benchmark for the site.
Staking out the system I design in AutoCAD.
I believe I cannot do this with just 1 receiver as I will sometimes be without cellular coverage. Would I be able to do it with 2 RS2+ units without cellular service?
Setting the benchmark seems easy enough, but I am not sure about the process from AutoCAD to Emlid Flow, to the field and actually staking out the corners. Is this possible?
Hello Argo, welcome and good luck with your projects !
From what you told, this looks perfectly fine to do with a pair of RS2+. This way you can overcome the fact that you have no cellular service by using the radio link between both. You will have to setup the base station on known coordinates in order to do proper stakeout. These coordinates can be obtained from the RINEX logging and post-processing with Emlid Studio or online services. Maybe you will have to be careful about the coordinates system you want to work with. Where are you based ?
You can import a DXF file in Emlid Flow and Emlid Flow 360. On the free Standard plan, only points will be imported. If you want to stake out line objects, you will need paid Survey plan.
I am based in rural Vermont, USA. I am now realizing this part about having to set the base station on known coordinates point. I cannot figure out how to go about getting that point.
Would using RINEX mean going out with one base unit, taking a reading on a point and marking it, then doing PPK on that point to get accurate coordinates, or is this not possible? Then I would go back out and stake out my design using the cm level (relative ) accuracy with the two RS2+ units using LoRa.
I need to use nav83 and navd88. I am just sort of now realizing that I may not really need absolute positioning to be very accurate, especially for horizontal measurements. It would however be good to have accurate absolute vertical measurements (not sure if that makes any sort of difference).
We were in touch with you via email. I just thought to share my answer here as well, in case someone comes up with the same questions.
A pair of Reach RS2+ will be just fine to work with a base and rover setup in an area without cellular coverage. Staking out your AutoCAD project will be also possible, but you need to make sure that you set the same coordinate system on the rover as in the AutoCAD. Is your project in geographic NAD83 coordinates, or do you apply a UTM projection as well?
I believe you need absolute accuracy in this case. Relative accuracy is needed to check that positions are precise relative to each other. For example, if you need to ensure that 3 points are on the same level. But if you want to get the precise elevations of points in NAVD88, then you need absolute accuracy.
Here is a guide about how to place the base. Since you need to do a precise stakeout, I see the following options for you:
Use OPUS or PPP Services. You’ll need to record the logs on the base, upload them, and wait for the precise position. Once you get it, you can come back to the work site and do a stakeout;
Get base position after static PPK. You’ll need to record the raw data log on your base and process it with the raw data log from the NTRIP Service.
Hi Julia, thanks for all the great info and links!
Hmm, I am struggling with this question a bit. I believe I apply a UTM projection (State Planes), since I don’t really want to use latitude and longitude in my work. I need all measurements in feet. Does that sound right? Does it become problematic one way or the other, or will either way work out?
Ah, it’s another projection. But sure, Vermont State Plane should also work fine, Emlid Flow supports it. You’ll just need to specify it when creating a survey project in the app.
