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Nov 28, 2016, 10:05 PM
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I enjoy seeing these new RTK/VRS based systems coming into the market. They are important for reliable accuracy and most importantly, maintaining vertical for your point clouds. Your efforts are awesome, and I was an early adopter of the Piksi (L1 only), so I'm aware of this hardware thing... But, I have some misgivings...

I'm a user of a VRS-based solution called the MobileMapper 300 by Spectra Precision. I pay an annual VRS subscription and this receiver gets 1cm x/y and 1-2cm z consistently within 100km of the nearest VRS base. I paid only $5000 for it (used, new $7800). Granted, its not an R10, but its a pretty awesome unit and all you need is a rod and an Android device. Not a whole lot. Drop some GCPs with some rattle can paint, grab a position, adjust for correction datum, create that CSV. Then, go fly, apply GCPs in Pix4D and voila, an airtight model. (Make sure you use a topo-shoe instead of a point as to not drop into the soil!)

Not to steal anyone's thunder, but correction datums and geoidal separation must be addressed, and applied if VRS correction datums exist to be transformed later back into WGS84. Not to mention other orthometric datums... And if ellipsoidal HAE instead egm96 is applied, that is SUPER important for vertical. I'm curious how all of this works with the OBS solution.

Furthermore, as to not continue to ruin anyone's efforts, the new school of BYOD GNSS systems are already taking shape with tiered services, for example, the Trimble Catalyst.
Last edited by frontrangeuas; Nov 28, 2016 at 10:20 PM. Reason: More
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Nov 28, 2016, 10:20 PM
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Thread OP
Thanks for stopping by and asking questions.

First for those who don't know a "VRS is a virtual reference station" what that mean is that you don't use a base. Therefore the cost of the gear is less... not quite half because we still need to provide a case and charger etc. but down quite a bit. So if we were to talk cost and compare apples to apples you paid twice what OBS is worth and received half the gear.

So why does OBS not use VRS you may ask? There are a few reasons.

1) you have to pay for a subscription to a VRS. Even if you don't use it for a few weeks... months... etc. Sure you can cancel but... why pay at all? OBS has it's own base station so you don't need to pay for a VRS. Now if you want to use a VRS subscription system sure you can use OBS that way too... but why not pay up front and never again?

2) you have to be inside a subscription supported area. There are still some areas that are not supported and these are usually remote areas that are suitable to drone survey. Depending on your location the VRS accuaracy may suffer as well.

Therefore to us the most reliable solution is to use your own base and not pay a subscription.

This does bring up a good point that I will discuss with the partners.

"Should we offer a VRS solution that would reduce the cost by about 30%?"

Please chime in so I can present the case.




Quote:
Originally Posted by frontrangeuas View Post
I enjoy seeing these new RTK/VRS based systems coming into the market. They are important for reliable accuracy and most importantly, maintaining vertical for your point clouds.

I'm a user of a VRS-based solution called the MobileMapper 300 by Spectra Precision. I pay an annual VRS subscription and this receiver gets 1cm x/y and 1-2cm z consistently. I paid only $7000 for it. Granted, its not an R10, but its a pretty awesome unit and all you need is a rod and an Android device. Not a whole lot. Drop some GCPs with some rattle can paint, grab a position, adjust for correction datum, create that CSV. Then, go fly, apply GCPs in Pix4D and voila, an airtight model.

Not to steal anyone's thunder, but correction datums and geoidal separation must be addressed, and applied if VRS correction datums exist to be transformed later. And, HAE if not egm96 is SUPER important for vertical. I'm curious how all of this works with the OBS solution.

Thanks
Last edited by saabguyspg; Nov 28, 2016 at 10:26 PM.
Nov 28, 2016, 10:30 PM
Registered User
Thread OP
RE the BYOD devices...

Rover pole? no thanks
RTK? range issues? no thanks
single frequency wait times? no thanks
rental? no thanks
wires, batteries etc? no thanks.

Two cubes in my back pack... yes please.
Support from people who know how to lay ground control and do drone surveys? Yes please.
weather resistant modules? yes please
other goodies we will annouce to make your life easier? well you have to wait but you will say Yes please


Steve
Nov 28, 2016, 10:36 PM
Registered User
You are right in the regard that VRS has its limitations. I do a little bit of work in NW Kansas/E. Colorado and sometimes we have to revert to SBAS... not ideal but 25cm isn't too bad. But, no wires, batteries, nada, just a light Seco pole and the magic disc!

It takes me about nearly 2 seconds once my 2m antenna is positioned level to establish a Fixed RTK solution with my system - collect corrected (NAD83 2011) xyz as an autoincremented GCP and off to the next location and store in a database on a server that fires a CSV export ready for Pix4D (SRS back to EPSG 4326 thanks to PostGIS). Because of this I can set 20+ control points in short order, depending on terrain and access of course.

Three minutes in the world of field work per GCP is significant, think about if you had just 20 GCPs, that would be an extra 60 minutes of waiting time.

Additionally, how many of us are working in areas without a VRS base and good cell service? Especially if they are construction sites?

Good conversation; I hope it is spirited and not disparaging.
Last edited by frontrangeuas; Nov 28, 2016 at 10:42 PM.
Nov 28, 2016, 10:41 PM
Registered User
Thread OP
Yup all good comments.

3 minutes is for pin point accuracy in any situation. Not having RTK means you ought to ensure you observe long enough to get good data.

2 seconds is a bit of an exaggeration on the other spectrum. With the topcon system we are waiting 5-10 seconds... and sometimes we have to dump the helmet... that takes time... I honestly don't think the few minute wait time is a killer here.

GREAT conversation. I am always up for some good talking and you may have opened this up to more people if we decide to create a VRS version.

However I know I put this to the surveying engineer and he poo poo'd it right away a couple weeks ago.

But if I can show interest from others such as yourself then we have to listen!

Have a great night, we are off surveying for three days so it may be quiet here.


Quote:
Originally Posted by frontrangeuas View Post
You are right in the regard that VRS has its limitations. I do a little bit of work in NW Kansas/E. Colorado and sometimes we have to revert to SBAS... not ideal but 25cm isn't too bad.

It takes me about nearly 2 seconds once my 2m antenna is positioned level to establish a Fixed RTK solution with my system - collect corrected (NAD83 2011) xyz as an autoincremented GCP and off to the next location and store in a database on a server that fires a CSV export ready for Pix4D. Because of this I can set 20+ control points in short order, depending on terrain and access of course.

Three minutes in the world of field work per GCP is significant, think about if you had just 20 GCPs, that would be an extra 60 minutes of waiting time.

Additionally, how many of us are working in areas without a VRS base and good cell service? Especially if they are construction sites?

Good conversation; I hope it is spirited and not disparaging.
Nov 28, 2016, 10:48 PM
Registered User
Thread OP
nice but I hate trucking around rover poles and bipods... and lets not forget the time it take to set up the bipod if we are talking seconds actual setup, observe and walk away you are a minute solid if you are good.

Especially for someone who has never set up a bipod before this cant take more than a few seconds.

What looks easier



Quote:
Originally Posted by frontrangeuas View Post
You are right in the regard that VRS has its limitations. I do a little bit of work in NW Kansas/E. Colorado and sometimes we have to revert to SBAS... not ideal but 25cm isn't too bad. But, no wires, batteries, nada, just a light Seco pole and the magic disc!

It takes me about nearly 2 seconds once my 2m antenna is positioned level to establish a Fixed RTK solution with my system - collect corrected (NAD83 2011) xyz as an autoincremented GCP and off to the next location and store in a database on a server that fires a CSV export ready for Pix4D (SRS back to EPSG 4326 thanks to PostGIS). Because of this I can set 20+ control points in short order, depending on terrain and access of course.

Three minutes in the world of field work per GCP is significant, think about if you had just 20 GCPs, that would be an extra 60 minutes of waiting time.

Additionally, how many of us are working in areas without a VRS base and good cell service? Especially if they are construction sites?

Good conversation; I hope it is spirited and not disparaging.
Nov 28, 2016, 10:48 PM
Registered User
Fine, fine, yeah it takes more than 2 seconds to set up the pole, LOL == I hope your survey guy has used a system like this because the 2 seconds thing is real once its leveled - furthermore, if we're "mapping" and not surveying, you certainly don't need mm accuracy for any of this.

I don't know about you guys, but my DSMs with this control that I'm getting are no better than 3" on the horizontal and no better than 6" on the vertical. It's the harsh reality of GSD/camera calibration/blur/lighting, etc... photogrammetry basics.

With that said, a 40K solution like the R10 isn't even a product you'd need to use for doing UAV control.

I look forward to seeing the end product. Best of luck.
Nov 28, 2016, 10:53 PM
Registered User
Thread OP
But yes I agree all you need is a few cm accuracy but we don't make false claims (by this I mean we don't want people to think they only need to sit for a few seconds because we don't have RTK feedback) and set the time to 3 minutes for safety.

To be honest you could get away with 30 seconds and that is competition for you to walk up, set a bibod, get our your phone and hold it steady to get your shot.

Obs will be walk up, set down obs, get your phone out and start logging.

Actual logging time will be exactly the same for the same accuracy. However a safety margin should be built in

Don't feel that I am defensive please... input is great!

Quote:
Originally Posted by frontrangeuas View Post
Fine, fine, yeah it takes more than 2 seconds to set up the pole, LOL == I hope your survey guy has used a system like this because the 2 seconds thing is real once its leveled - furthermore, if we're "mapping" and not surveying, you certainly don't need mm accuracy for any of this.

I don't know about you guys, but my DSMs with this control that I'm getting are no better than 3" on the horizontal and no better than 6" on the vertical. It's the harsh reality of GSD/camera calibration/blur/lighting, etc... photogrammetry basics.

With that said, a 40K solution like the R10 isn't even a product you'd need to use for doing UAV control.

I look forward to seeing the end product. Best of luck.
Nov 28, 2016, 11:14 PM
Registered User
Not at all, I appreciate what you guys are doing... as I mentioned I helped the Swift guys out with their campaign, and used the Piksi but unfortunately wasn't a real production level device.

Been around this for awhile now, played with every GCP style and hours of adjusting correction datums and geoids to ensure vertical was spot on... not an overnight thing, at least for me. I have definitely been there, done that, and I pride myself for being in the trenches...

So, I speak of GCP setting efficiency because it is a VERY tedious process and takes hours to do it right. I've spent countless hours doing this for various jobs but its all because the client needs gnats-arse accuracy. I have no problems as I'm still able bodied enough to do it plus you get good exercise!

It does take about a minute or two to do everything. In that photo I set permanent control with lath and spikes to make the triad. Carrying that out there isn't easy. However its permanent and don't have to set any more control unless it gets disturbed. I've also gotten good at my collects so its streamlined now. A newcomer would struggle...

I just think its important to show my angle to this as its very old school yet works like a champ at the same time. I am hoping to not have to do this someday, so I'm leaning HARD on you guys to make that happen!
Nov 28, 2016, 11:38 PM
Registered User
Thread OP
can you fire me a PM with your email please? If we get funded there may be some ideas I want to run past seasoned pros like yourself.


Quote:
Originally Posted by frontrangeuas View Post
Not at all, I appreciate what you guys are doing... as I mentioned I helped the Swift guys out with their campaign, and used the Piksi but unfortunately wasn't a real production level device.

Been around this for awhile now, played with every GCP style and hours of adjusting correction datums and geoids to ensure vertical was spot on... not an overnight thing, at least for me. I have definitely been there, done that, and I pride myself for being in the trenches...

So, I speak of GCP setting efficiency because it is a VERY tedious process and takes hours to do it right. I've spent countless hours doing this for various jobs but its all because the client needs gnats-arse accuracy. I have no problems as I'm still able bodied enough to do it plus you get good exercise!

It does take about a minute or two to do everything. In that photo I set permanent control with lath and spikes to make the triad. Carrying that out there isn't easy. However its permanent and don't have to set any more control unless it gets disturbed. I've also gotten good at my collects so its streamlined now. A newcomer would struggle...

I just think its important to show my angle to this as its very old school yet works like a champ at the same time. I am hoping to not have to do this someday, so I'm leaning HARD on you guys to make that happen!
Nov 30, 2016, 04:41 PM
Registered User
Sent a PM, have no idea if it worked. #simplemachinesneedstogo
Nov 30, 2016, 10:25 PM
Registered User
Thread OP
Yes I got it sorry, we are out in the field for a few days and have some catching up to do when we get back.

Kickstarter has a couple supporters but we have gained a lot of subscribers. I think as we release more information and show that we actually know what we are talking about we will gain momentum.

Looking forward to an exciting few weeks.

Steve
Dec 08, 2016, 02:33 PM
Registered User
Thread OP
A friend linked this to me, good reading

http://www.expouav.com/news/latest/a...ent=newsletter
Dec 12, 2016, 02:05 PM
Registered User
Thread OP
For those of you still following progress we are supplying two pro grade dual frequency antennas with OBS. If you do a little research that's $700 CAD in antennas alone.

http://shoutout.wix.com/so/6LZq6P2C#/main
Dec 14, 2016, 03:58 PM
Registered User
Thread OP
I started a facebook group for OBS if anyone prefers

https://www.facebook.com/groups/400331106972383/photos/


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