For the past month I have been working with Cody Remington?ÿfounder at?ÿ?ÿBAAM Tech
They sell and install a $2500 PPK kit for any DJI Phantom 4 and Inspire 2. The system utilizes GPS L1/L2, GLONASS G1/G2, BeiDou B1/B2, Galileo E1/E5b and SBAS constellations. They include a software for post-processing?ÿthe RINEX log files from your Survey grade base station and the log file from the sUAS system.
The process is very simple, here is a brief step by step;
- You set up your GNSS base receiver to log static data at?ÿ1-second epochs.
- Place the sUAS with PPK system on the center of the Iron Cross aerial target (supplied with the system from BAAM Tech). This stores the initial point of the PPK as your single calibration point.
- Launch your sUAS mission. The system triggers the camera to?ÿsynchronize with the static log file. All static data is stored in the included USB drive on the system. The PPK receiver uses the drone power?ÿsupply, so no additional charging.
- The Post-processing?ÿsoftware from BAAM Tech?ÿcomputes the Lat/Lon/Ell and replaces the GeoTag for each photo of your aerial mission.?ÿ
- Mark only the launch point on 5 photos?ÿin Pix4d, and process.
Here is a snippet of accuracy report from Pix4d.
Complete Pix4d report.
Lee, it would be worthwhile repeating step 2 at the end of each flight as a check that all was well.
Lee, thanks for the information.?ÿ I'm definitely interested in this.?ÿ How long did your static run in the this project example??ÿ If you didn't put out the other targets as checkpoints, you could complete this entire mission in way less than an hour.?ÿ Does the static need to run for a minimum amount of time to achieve these accuracies?
Andrew,
The entire static was only 20 minutes, including the flight time.?ÿ If you contact BAAM Tech, please mention my name.
If your not familiar with how PPK and Rapid Static can work together, I'll try to explain it here.
Great Post Lee, Thank you for sharing.
Thanks for posting this Lee and once again it was good talking with you. I sent my P4P in today and am already anxiously awaiting its return.
Gregg
Very interested but worried that the dji care refresh is invalidated with this augmentation.
Lee, what kind of results do you get with zero GCPs?
Andrew,
The results I posted is virtually zero GCP's. The drone?ÿcreates the initial point, which is used for a single GCP calibration.
Just like any use of static GPS, it is very important to place your Base in an area with?ÿwide open sky.?ÿ At my office, there are a lot of large White Pine trees over 80ft tall. I launched a test mission with the base getting just 5 US and 4 Glonass SV's. The PPK post-processing?ÿproduced all float positions. Rendering the data useless. But fortunately I had three GCP's, the launch point, and two painted cross's on pavement. Along with the BASE as a check point. This salvaged the entire project. Proving it is important to have at least three GCP's on all projects.
Thanks Lee. I??m trying to evaluate what kind of results to expect in areas where placing targets is difficult or unsafe for various reasons.?ÿ
I find that we always need to leave a few control points?ÿfor a survey baseline. These points don't need to be around the perimeter, just have them a few hundred?ÿfeet apart. I like to paint a cross on the highway, leaving a PK nail in the center.
Thanks for this post. I have a question: is there a range limit from the base to where the drone is flying and what is it? Let's say I have a 10 mile linear project and because of obstruction I can only put my base around the 1 mile maker (not the 5 mile marker), will this affect the quality of the data?
Very unwise.Comparing data quality when we have had two bases running shows that you shouldn't really go beyond 4km. from the base position. It's good practice to have the base within sight of the flying position.
I'm assuming you are moving up with the UAV and not simply flying beyond line of sight. If the main base is left somewhere safe for the duration of the job you should use a second base moving up with you. It will fix from the main base during the duration of each flight.
Alternatively, if you only have one base station then you might need to fix a couple more positions along the line before you do the flying.
I'm testing the use of two static Base stations (at 1 second epoch). I'm trying to figure out how to apply the corrected GeoTags with Pix4d and?ÿpost-processing?ÿwith Topcon Magnet Tools. This yields?ÿvery good results and I find it much easier than the BAAM Tech software.
My projects are all less than 100 acres, so the base stations are not too far apart.
If the poster above is trying to use a CORS for a base, this could have two downfalls.?ÿ 1) Distance is likely too far from your project. 2) Most CORS are not recording 1-second Epoch with GNSS.
It's amazing how accurate the flight lines are with the Phantom 4 Pro v2 (without RTK). See image below.
?ÿ
We tend to use two base stations on linear jobs such as coastlines and pipelines, leapfrogging the units as we go along and with around 3-4km spacing maximum. The nearest base to the flight is used for the PPK.?ÿ The spacing is determined by the fact that we are also using them to set GCP and check points and we don't want the RTK dropping out during that operation. If you put the second base up first (if that makes sense) then that sits through three flights as the other base leapfrogs. By that time it should have a good fix. The remainder of the bases then fix between themselves on short lines. On a large job the last but one base can also site for three flights and provide another full fix.
Our jobs are typically larger than Lee's sites, although not as neat and tidy - one advantage of a rotary over a fixed wing - so there is more need to have multiple base positions.
Lee, any news on how you're getting on with the BAAM TECH please? I'm thinking of putting one on my M200.
Yes it works great. I'm flying three projects this week with it.
Is anyone having good luck with this sUAV PPK setup?
It's been awhile since this first posted
Any updates? reviews
