Hi everyone. I work in a landscape ecology lab where we routinely create 3-dimensional point clouds from both drone imagery and Lidar scanning to learn about forest structure. We recently realized that more accurate position information would be really helpful to compare point clouds of the same area at different time and from different sources. We have become interested in the RTK Facet for use as a base station to provide RTK correction via radio link in remote areas (low to no cell service) to a DJI Mavic 3E drone and to a Reigl VZ-400i terrestrial laser scanner. My question is pretty simple - will it work?
I’ve gotten a little bewildered trying to read setup guides for these pieces of equipment and now I feel a little unsure that everything is compatible. Does the RTK facet provide correction information in a useable format to the drone and Lidar scanner? I realize I’m asking about non-Sparkfun products, but I was hoping someone with more experience than I might have an answer. Thanks very much.
The easy answer is to use identical GNSS equipment for both your base and rover, or at least GNSS equipment from the same manufacturer that will support your configuration.
You might get better answers from the drone community. I read about a lot of drone pilots doing similar things to what you want do to.
I’m not clear on what your rover actually will be. Your title says the rover will be a Juniper Geode, but the post makes me think your drone will be the rover? Is that an RTK rover? What GNSS receiver chip is in it? I’d imagine you can put SparkFun board as a rover on your drone to match with the Facet. Or will the Geode be on the rover? Or will you use the Geode to set GCP targets for your drone scanning?
Anyway, a Facet base and Geode rover might work, assuming you can get a radio comm link working. The RTCM standard was designed for this. A datasheet for the Geode says it supports RTCM, and most current GNSS receivers sold to be used as Rovers do support RTCM. The RTK Facet does transmit standard RTCM data. One potential sticking point is some GNSS receivers in a Rover configuration require particular RTCM messages (there are many) and a different GNSS receiver may not transmit that particular RTCM message because it’s not strictly required for RTK.
RTK takes a fair amount of time and effort to get working and even more to master it. Especially if you are mixing and matching manufacturers.
Thanks for the reply, toeknee. My head is a jumbled mess of RTK information so I’m not surprised my post was confusing. To clarify, we currently have Juniper Geode GNS2s, a DJI drone, and a Riegl lidar scanner all of which we would like to use with an RTK base station, so all of those would potentially be rovers. It makes sense economically to get one base station that would work with all.
I’ll check in the drone community. Also, your suggestion to use an RTk rover to set GCP targets could work for both the drone and the lidar scanner. That seems like a simpler solution.
Are radio comm links hard to get working? I haven’t investigated that yet. Thanks again!
In this case, what I have done has been to take raw data with the RTK Facet and carry out the flights with the Mavic 3E with GNSS module and record raw data and then post-process the drone data in Emlid studio.
I have previously post-processed the RTK facet data in Leica Infinity, here I will directly read the ubx file generated by the antenna.
I have performed PPK this way because I do not have a radio for the link
Post processing kinematic (PPK) is an excellent suggestion. Saves a lot of fussing about in the field when time is short, and no need to be sure your radio comm link is working.
RTKLIB or Emlid Studio (which uses RTKLIB IIRC) both are free and both work well.
javierlq21 thanks for bringing ppk up as a solution. I agree with toeknee that is an excellent idea. I think I was getting carried away with the RTK stuff, but there’s no need really to have that accuracy real time. I guess the same is true for the lidar scanner.