Any successful NTRIP-based workflows with Enterprise RTK?

[FlyoverGreg]

Has anyone successfully used the Enterprise RTK in a mapping mission and:
1. connected it to an NTRIP network, and
2. used the received corrections to update the lat/lon/elevations of their images (either real-time or via some PPK process).

If so, could you share that and a little bit about your setup (which NTRIP network, which message format/version (RTCM3, etc.) and workflow, and anything else you think would put a prospective buyer at ease. I want to buy an Enterprise w/RTK today, but I've not yet found anyone describing a successful workflow. May just be my inability to find the right thread or video.

 

[yarrr]

I'm not sure that I can put your mind at ease, but I'll share my experience over the last few weeks.

Fairly small sample size, but in each of the four mapping missions that I've completed, the RTK has disconnected at least once. I've only actually processed the images (Pix4d) from one flight. The results were serviceable.

To answer your specific questions:
1a. I can connect and get a fix from our state CORS network. Format is RTCM v3.2.
2a. I have not specifically used this workflow for mapping, maybe I'll try it this week.

1b. My typical workflow involves setting an Emlid Reach RS2 at a known point (via its own network connection), and connecting it to the Evo Smart Controller via the EmlidCaster option.
2b. Using this connection, the geotags are read by Pix4d as Lat Long with 8 decimal digits, and altitude (m) with three decimal digits. O/P/K and image accuracy are also read by Pix4d.

I've documented the PPK workflow here. Results seemed pretty good (within a couple centimeters of the fixed status RTK data). In PPK, you loose antenna offset (which is easy enough to manually change), and lever arm calculations (assuming Autel actually implemented this in their RTK to EXIF process).

Was planning to document this elsewhere, but since you are a prospective buyer, I'll list some pros and cons of the E2E here.

Pros:

1. It's not made by DJI
2. Automatic geotagging via EXIF
3. Decent camera specs
4. Decent images mapping on "auto mode" (clearly this is a huge no-no, but I tried it anyway just for fun)
5. Decent battery life

Cons:

1. Finicky NTRIP formatting/requirements limit base station choices see here.
2. RTK disconnects - I still need to diagnose this more, but it is very troubling. Note that hitting 'disconnect' and 'login' reestablished corrections.
3. Speed/overlap limitations: best I could achieve seemed to be 10 m/s, 84% overlap at 120m. I'd like this to be higher, particularly at something like 60m agl.
4. The vehicle burns a bunch of time turning around at the end of transects. It's like- slow down, stop, think, turn, go slow, turn, think, then accelerate on the next line. This is probably related to maintaining GNSS fix, but it is really annoying.
5. Mission planning is unpleasant on the Smart Controller
6. Rolling shutter (really no longer an issue when using Pix4d).
7. Lack of support
8. A bunch of stuff unrelated to mapping:
   1. "Enterprise" accessories are silly
   2. Carrying case is a joke. A very bulky and heavy joke.
   3. Panorama features
   4. Auto ("smart") flight features don't seem as good as Parrot or 3DR, but this is not my area of expertise
   5. Smart Controller can't be charged during flight
   6. Smart Controller button customization doesn't seem to work

I really can't say if price is a pro or con. It seems high for me, having worked on better spec systems from a DIY approach. So I had high hopes that the E2E would be smooth and polished professional solution. I don't believe that this to be true. However, I'm not aware of other off the shelf systems that would be cheaper for mapping.

Hope that was at least a little helpful, happy to expound on further questions. Good luck!

 

[FlyoverGreg]

I'm not sure that I can put your mind at ease, but I'll share my experience over the last few weeks.

Fairly small sample size, but in each of the four mapping missions that I've completed, the RTK has disconnected at least once. I've only actually processed the images (Pix4d) from one flight. The results were serviceable.

To answer your specific questions:
1a. I can connect and get a fix from our state CORS network. Format is RTCM v3.2.
2a. I have not specifically used this workflow for mapping, maybe I'll try it this week.

1b. My typical workflow involves setting an Emlid Reach RS2 at a known point (via its own network connection), and connecting it to the Evo Smart Controller via the EmlidCaster option.
2b. Using this connection, the geotags are read by Pix4d as Lat Long with 8 decimal digits, and altitude (m) with three decimal digits. O/P/K and image accuracy are also read by Pix4d.

I've documented the PPK workflow here. Results seemed pretty good (within a couple centimeters of the fixed status RTK data). In PPK, you loose antenna offset (which is easy enough to manually change), and lever arm calculations (assuming Autel actually implemented this in their RTK to EXIF process).

Was planning to document this elsewhere, but since you are a prospective buyer, I'll list some pros and cons of the E2E here.

Pros:

1. It's not made by DJI
2. Automatic geotagging via EXIF
3. Decent camera specs
4. Decent images mapping on "auto mode" (clearly this is a huge no-no, but I tried it anyway just for fun)
5. Decent battery life

Cons:

1. Finicky NTRIP formatting/requirements limit base station choices see here.
2. RTK disconnects - I still need to diagnose this more, but it is very troubling. Note that hitting 'disconnect' and 'login' reestablished corrections.
3. Speed/overlap limitations: best I could achieve seemed to be 10 m/s, 84% overlap at 120m. I'd like this to be higher, particularly at something like 60m agl.
4. The vehicle burns a bunch of time turning around at the end of transects. It's like- slow down, stop, think, turn, go slow, turn, think, then accelerate on the next line. This is probably related to maintaining GNSS fix, but it is really annoying.
5. Mission planning is unpleasant on the Smart Controller
6. Rolling shutter (really no longer an issue when using Pix4d).
7. Lack of support
8. A bunch of stuff unrelated to mapping:
   1. "Enterprise" accessories are silly
   2. Carrying case is a joke. A very bulky and heavy joke.
   3. Panorama features
   4. Auto ("smart") flight features don't seem as good as Parrot or 3DR, but this is not my area of expertise
   5. Smart Controller can't be charged during flight
   6. Smart Controller button customization doesn't seem to work

I really can't say if price is a pro or con. It seems high for me, having worked on better spec systems from a DIY approach. So I had high hopes that the E2E would be smooth and polished professional solution. I don't believe that this to be true. However, I'm not aware of other off the shelf systems that would be cheaper for mapping.

Hope that was at least a little helpful, happy to expound on further questions. Good luck!

Cannot thank you enough for your detailed reply. I will absorb this fully, as well as your PPK thread. I think I am going to wait on the Enterprise/RTK unit---hopefully with a little bit of maturity they can get the kinks out of the disconnecting issue and better document some workflows.

Been flying a long time, and off and on creating orthomosaic maps of cemeteries, mapping everything from 1 acre to 125 acres. Have gotten really into that the last 4+ months and recently decided to get more serious about the exactness of the GCPs. So I got a couple of Emlid Reach RS2s. Being in Texas with no public access to our CORS network, I finally got tired of multi-hour observations getting OPUS-based known-points and signed up with an NTRIP service. Seemed expensive but the time-savings made it a no-brainer. Anyway, am in constant search for ever more efficient workflows and am convinced airborne RTK will eventually be as simple and effective as I hoped it would be already. I'm not terribly interested in the P4Pro RTK mainly because we've experienced weeks on end with 25-35 mph winds + gusts and I know the P4 won't cut through that worth a flip. I like my chances with the Evo II pro or enterprise. Anyway, your non-DJI logic rings true with me. I've had decent success with them but I want to at least dabble with another direction. I'm not at all against DIY but haven't yet figured out which FCs work with which mission-planning (and execution) software. I've decided to go ahead and start learning the Autel eco-system with just a regular Evo 2 Pro, then hopefully in a few months, some pioneers like you (and hopefully Autel themselves) will share a workflow that lights my fire.

I'm sure I'll have some more specific questions later, but I totally agreed with all your thoughts that could be weighed by just a prospective purchaser. The price seems a little high, the smart controller seems like it's just a way to peddle hardware----all you're buying is a constrained android tablet with built in sticks and paying at least double what it ought to be price-wise (my opinion). I hate that I have to get a hard-case with the Enterprise or the Evo II Pro---no one seems to sell just the base unit Pro without that being part of the deal. I've got two hard-cases for Phantoms gathering dust in my garage. I drive a Nissan Pickup. I don't want to have to buy a Suburban to haul around unnecessary luggage. As for mission planning, I did my first UGCS mission today with a Mavic 2 Pro. It was pretty clunky but I like the portability of KML. I love Pix4D capture's simplicity except I'd still rather create missions on a regular computer rather than on a tablet.

One question. Have you tried Emlid Studio yet? I've done several PPK projects with some success. The Drone Mapping Tools guy (from Mississippi) has been a big help: https://www.youtube.com/channel/UC10YBIvPVV72c9NU-1WNKhg.

Will likely shout back at you later. All the best of luck to you and thanks again for your response!

 

[yarrr]

Lots to digest there. You're probably smart to put off the purchase. One other thing to consider is the Evo II RTK (not Enterprise), which may or may not be available at any given time. You loose out on the carbon arms and Smart Controller- which you may view as a benefit. Unclear if flight time is better or worse than Enterprise. @jmason702 loves his and was very helpful when I was considering shifting to Autel.

For mission planning, I'm shocked that Autel Explorer doesn't have a corridor option. I've been looking into avenues for importing missions from other applications, but haven't figured it out yet. The app update from last week supposedly allows import of KML, so Autel truly is making progress.; and something like Litchi or QGCS may be an option. On other vehicles I use Mission Planner (desktop) and Pix4dCapture.

Emlid Studio is a nice GUI of RTKLib (CONV/POST/PLOT). I've used it a fair amount with Emlid RS2 base and M/M2 rovers. I like it, and hopefully it will be updated to work with Autel for PPK.

 

[jmason702]

I just bought another V1 RTK unit, I like it very much, not sure what is going on with Enterprize as I don't own one. But there are 2 or 3 units left out in the world to get, and I heard Autel is coming out with EVO RTK V2

 

[Sérgio]

boas
comprei um EVO 2 RTK e estou satisfeito.
Ligo é REDE SERVIR (Portugal) e tem sido pacífico.
tenho o inseri os dados de acesso (Usuário, IP, etc) e funciona bem.
lamento é o Smart Controller não ter lugar para colocar um cartão telefónico e tenho que partilhar o telemovel por wi-fi.

 

[Junior]

A couple Evo 2 RTK units here:
Autel Robotics EVO II RTK – Kuker-Ranken (KR)

 

[jmason702]

here are mine

 

[jmason702]

Here is a data set of 50 Acers, with no GCPs if you would like to process it with your software to see the accuracy. EVO RTKEVO RTK 50 - Google Drive
2 battery flight

 

[jmason702]

Smart Controller can't be charged during flight

WOW, the V1 can be charged during flight... I have done it.

 

[elphtrooper]

WOW, the V1 can be charged during flight... I have done it.

Yeah that is a really strange decision to share hardware resources between the storage system and the radio or whatever it takes over. If you are connected to the drone and plug a USB-C in it disconnects from the drone.

 

[reynolds8126]

I have had success with the V2 RTK. We already have survey grade GNSS equipment for our other activities. We are using a Trimble GNSS receiver as our NTRIP caster. The new Trimble base stations broadcast a wireless network that allow the Smart Controller to connect and receive the NTRIP directly from the base. The broadcast is RTCM v3.2 or higher.

Regardless who you use as the NTRIP Caster, simply connect the controller to the appropriate network (internet or intranet) and program the IP, Port, User Name, and Password settings in the controller app.

After flying nearly 20 RTK mapping missions, ranging from 20 acres to 600 acres, I only experienced a loss of RTK fix once and it was only momentary.

The most recent firmware update did break some features, including the creation of the Rinex and timestamp files; however, the update did fix the Smart Controller charging issue. Prior to release 2.3.8, connecting the Smart Controller to a charging source via USB-C would immediately disconnect the controller from the Evo. Firmware 2.3.8 now allows simultaneous charging of the Smart Controller and communication with the Evo.

 

[elphtrooper]

I have had success with the V2 RTK. We already have survey grade GNSS equipment for our other activities. We are using a Trimble GNSS receiver as our NTRIP caster. The new Trimble base stations broadcast a wireless network that allow the Smart Controller to connect and receive the NTRIP directly from the base. The broadcast is RTCM v3.2 or higher.

Regardless who you use as the NTRIP Caster, simply connect the controller to the appropriate network (internet or intranet) and program the IP, Port, User Name, and Password settings in the controller app.

After flying nearly 20 RTK mapping missions, ranging from 20 acres to 600 acres, I only experienced a loss of RTK fix once and it was only momentary.

The most recent firmware update did break some features, including the creation of the Rinex and timestamp files; however, the update did fix the Smart Controller charging issue. Prior to release 2.3.8, connecting the Smart Controller to a charging source via USB-C would immediately disconnect the controller from the Evo. Firmware 2.3.8 now allows simultaneous charging of the Smart Controller and communication with the Evo.

They fixed the OBS/MRK issue on an Enterprise model w/ RTK so it may be compatible and available soon. It also fixed some of the inconsistencies of battery swaps and re-establishing RTK but it doesn't sound like that was an issue with the V2 RTK-only.

 

[reynolds8126]

The vehicle burns a bunch of time turning around at the end of transects. It's like- slow down, stop, think, turn, go slow, turn, think, then accelerate on the next line. This is probably related to maintaining GNSS fix, but it is really annoying.

Under the current flight characteristics, a 30 minute estimated flight time results in two batteries and over 45 minutes of flight time.

I mentioned this behavior to Autel's support. I see no reason the Evo needs a high precision location for the end waypoints. Nor do I see a reason for the time delay upon reaching those end waypoints. A VTOL UAV and a fixed wing UAV will map a site equally as well as one another. A fixed wing UAV won't delay at an endpoint waypoint and a fixed wing UAV is less precise in reaching that end waypoint. The Evo should simply mimic the fixed wing UAV, flying toward the end waypoint location, with a relatively loose error circle in achieving that waypoint location, simultaneously turning and flying toward the next waypoint at the beginning of the next line (the same loose error circle scenario applies here also), a commence flying the next waypoint flight line. There shouldn't be a time delay at either the end of one line, or the beginning of the next line.

Support acknowledged my suggestion and forwarded the suggestion to their development team.

 

[elphtrooper]

I see no reason the Evo needs a high precision location for the end waypoints.

Yep. The whole point of the RTK is that it is writing the cm-accurate data not perfectly navigating the aircraft. Our tickets are in support and engineering as well. We need these things tight if we are going to start deploying them to pilots. As of right now... nope.

We get about a 27 minute flight so far with landing it at 8-10%. Long transects are definitely a battery killer in pretty much every mapping software. I want to run corridors with two lanes from a position that allow takeoff and landing at the same location. Basically just running a closed loop. Not flying half a mile to one end and flying back from that same end. That's actually not a very safe method.

Drifting is undoubtedly the best 180deg you can do in this case.