Topodrone PPK Kit

[dougcjohn]

Michael, visited your Chasco web site... nice Web site & layout. Several nice videos, enjoyed the Old San Antonio bridge clip... nice artistic touch coming down between the 2 cranes.

If you wouldn’t mind or able to share, would enjoy examining some 2D or 3D images on some of your projects. I noticed in one video a Phantom shadow, are you using P4P RTK for your aerial work?

 

[adm_geomatics]

Doug, in short, GCPs, and drone based RTK and PPK serve the purpose of removing distortion in the resulting surface mesh and relating or tying the mesh to a known coordinate reference system (CRS).

If the area of interest is either small in scale (like individual stockpiles), or has no requirement to be tied to a CRS, then the extra work is not necessary. On the other hand, as the scale of the area grows, or there is a requirement for points on the ground to align with points on the ground as referenced to a CRS, then proper use of GCPs, and or RTK/PPK come into the picture.

So, for general construction progress orthos that are not used to calculate much of anything and are just used as a reference, the GCP workflow doesn't add much value. But, for example, if the surface mesh you are producing is going to be used by a grading contractor to see how much material they need to remove or haul in, then it absolutely needs to have a working ground control workflow that can be verified.

Right on. We like to think of all of these options as a la carte and potentially supplemental to each other. Sometimes you need rough GCP's just to get 2D alignment so that maps are relative for side-by-side comparisons. Other times you need more accurate GCP's for good absolute or site relative georeferencing of the map and better grade. Sometimes just PPK can run a project that only needs flight to flight comparison to itself. Then at last there are times that you need the absolute best accuracy that you can get in all criteria in which you could use PPK and GCP's. The way we use PPK is to reduce the need for so many GCP's particularly as Dave stated when the projects get really big, but in our theory GCP's are always needed to tie to specific designs and coordinate systems. Instead of 20 for a 100 acre project we might only need 5-6 and will still most likely end up with a more accurate map.

 

[adm_geomatics]

Michael, visited your Chasco web site... nice Web site & layout. Several nice videos, enjoyed the Old San Antonio bridge clip... nice artistic touch coming down between the 2 cranes.

If you wouldn’t mind or able to share, would enjoy examining some 2D or 3D images on some of your projects. I noticed in one video a Phantom shadow, are you using P4P RTK for your aerial work?

Thank you, glad you enjoyed it. PM me your email and I'll send you some examples.

We use Phantom 4 Pro's and Yuneec H520's. Both box stock and PPK augmented of each.

 

[dougcjohn]

Thank you, glad you enjoyed it. PM me your email and I'll send you some examples.

We use Phantom 4 Pro's and Yuneec H520's. Both box stock and PPK augmented of each.

I’ve got a H520 in Inventory... may be my area & interferences but range is not good. Like the quite stable platform, although would like to see more app development both OEM and 3rd Party.

I’ll send over a PM, thanks!

 

[Dave Pitman]

@Salty Sam . In this discussion about when a "corrected" workflow is necessary, or adds value. I would add that learning the workflow and gaining experience is also a value...to you. If you have a construction site that has some benchmarks shot in and you can get their coordinates and either see them in the imagery or cover them with targets so that you can identify them in order to add GCPs to your otherwise refernce ortho. It will help you build your experience and prepare you for when a corrected workflow is a requirement.

You can also get some gear and start shooting in points yourself. But that is a more involved and expensive step. And, I would be very careful about taking responsibility for their accuracy depending upon the use case. Using the client's control is much safer, liability wise when you are not a survey professional.

 

[adm_geomatics]

I’ve got a H520 in Inventory... may be my area & interferences but range is not good. Like the quite stable platform, although would like to see more app development both OEM and 3rd Party.

I’ll send over a PM, thanks!

Yes! The standard H520's range is horrible, particularly when it turns and is facing you. It completes large maps successfully, but is not stable enough of a signal to do free-flight images and videos. We did allot of beta testing with them configuring the flight patterns and got to play with the RTK, but unfortunately our session was cut short of the development of the H520E which was primarily in the UK. Just sent a PM with some links.

 

[adm_geomatics]

@Salty Sam . In this discussion about when a "corrected" workflow is necessary, or adds value. I would add that learning the workflow and gaining experience is also a value...to you. If you have a construction site that has some benchmarks shot in and you can get their coordinates and either see them in the imagery or cover them with targets so that you can identify them in order to add GCPs to your otherwise refernce ortho. It will help you build your experience and prepare you for when a corrected workflow is a requirement.

You can also get some gear and start shooting in points yourself. But that is a more involved and expensive step. And, I would be very careful about taking responsibility for their accuracy depending upon the use case. Using the client's control is much safer, liability wise when you are not a survey professional.

Definitely take advantage of the layout crews of construction companies. Then you are guaranteed to be on the same control the onus for the accuracy of that control is on them. You can get the project surveyor (PLS) involved, but they can be quite expensive depending on how many targets you need to set. This is a case where PPK can be a big cost savings.

 

[dougcjohn]

Yes! The standard H520's range is horrible, particularly when it turns and is facing you. It completes large maps successfully, but is not stable enough of a signal to do free-flight images and videos. We did allot of beta testing with them configuring the flight patterns and got to play with the RTK, but unfortunately our session was cut short of the development of the H520E which was primarily in the UK. Just sent a PM with some links.

I’ve only tested the H520 free flight and couldn’t believe the short range... very disappointing for such a pricey platform! Was thinking of trying my Titan Switch Antenna Amp or picking up one of the other... Alien, I believe makes one adaptable to Yuneec ST16 RC.

Since Pilot App is only supported for mapping, you’re stating it will run the mission after loosing RC connection? That’s good to know but a little concerning if for some reason need to abort and regain control.

I may get it back out this Spring and try it. I basically shelved it hoping new features, 3rd party SW, or updates would arrive. But it sounds like it’s a EOL platform since the 520E was introduced... which I question it’s lifespan seeing Yuneec’s support and upgrade path has been minimal, scattered and slow. With the poor development behind the H520, what's the incentive to take a chance on the H520e... when other solutions like DJI provide ample range & support that includes 3rd party.

The H520 ST16S states 1.6km and the ST16E states 7km. I didn't even see the 1.6km distance.
In your tests, did you determine the difference? I'm leading to if the ST16S could use any of the ST16E components to gain distance or if the ST16S with a range extender Amp would provide similar distance.

 

[adm_geomatics]

That’s good to know but a little concerning if for some reason need to abort and regain control.

With the H520 it was usually the video connection that would break and if the radio link dropped for long enough it would RTH. That happened rarely to us.

But it sounds like it’s a EOL platform since the 520E was introduced... which I question it’s lifespan seeing Yuneec’s support and upgrade path has been minimal, scattered and slow.

Yes, it is EOL. I know some people have had some issues with it, but both of ours have been pretty bulletproof and DataPilot has everything we use it for so 3rd party support was never an issue. Of course we went through a few firmware glitches and a few times the landing gear didn't perform correctly but that's an issue with not maintaining the hardware. Mechanical parts need care. I did some testing with 3DR SiteScan on an iPad for them and am not a big fan of SiteScan, but they ended up making a model specific to 3DR so I am glad it went that way.

what's the incentive to take a chance on the H520e... when other solutions like DJI provide ample range & support that includes 3rd party.

The H520 ST16S states 1.6km and the ST16E states 7km. I didn't even see the 1.6km distance.
In your tests, did you determine the difference? I'm leading to if the ST16S could use any of the ST16E components to gain distance or if the ST16S with a range extender Amp would provide similar distance.

The biggest improvement is the radio system. They now use an ODFM-based system hence the increase in distance. They also fixed the drone's antenna locations which I think was a major contributor to the H520's range issues. We do have one of the 4Hawks range extenders and it helps, but the whole system itself is poorly engineered in communications. I don't think they expected us to want to fly over 2000ft which was our most common distance cap. With the 4Hawks we could get to 3000ft in perfect conditions, but even it averaged about 2500ft or so which is pretty much VLOS so it worked.

I just ordered the H520E RTK and looked forward to that journey.

 

[dougcjohn]

With the H520 it was usually the video connection that would break and if the radio link dropped for long enough it would RTH. That happened rarely to us.


Yes, it is EOL. I know some people have had some issues with it, but both of ours have been pretty bulletproof and DataPilot has everything we use it for so 3rd party support was never an issue. Of course we went through a few firmware glitches and a few times the landing gear didn't perform correctly but that's an issue with not maintaining the hardware. Mechanical parts need care. I did some testing with 3DR SiteScan on an iPad for them and am not a big fan of SiteScan, but they ended up making a model specific to 3DR so I am glad it went that way.


The biggest improvement is the radio system. They now use an ODFM-based system hence the increase in distance. They also fixed the drone's antenna locations which I think was a major contributor to the H520's range issues. We do have one of the 4Hawks range extenders and it helps, but the whole system itself is poorly engineered in communications. I don't think they expected us to want to fly over 2000ft which was our most common distance cap. With the 4Hawks we could get to 3000ft in perfect conditions, but even it averaged about 2500ft or so which is pretty much VLOS so it worked.

I just ordered the H520E RTK and looked forward to that journey.

Yes, video link extremely poor... although I was meaning RC link, would misbehave, non-responsive intermittently.

I was curious if you were turning off RTH on Pilot Map mission and it was continuing mission if RC link dropped; similar to MapsMadeEasy option with DJI.

On my older Typhon Pro, I changed the Craft's antennas with small SMA 3" posts.... helped the 420 significantly... better range than 520 stock.

Good luck with 520E.

 

[JOECNC2006]

I would stick to a mechanical shutter if you are serious in surveying mapping. the M2P does not have one it uses a rolling shutter.

 

[adm_geomatics]

I would stick to a mechanical shutter if you are serious in surveying mapping. the M2P does not have one it uses a rolling shutter.

I don't think there is another drone with an integrated camera that has a global shutter is there?

 

[yarrr]

I would stick to a mechanical shutter if you are serious in surveying mapping. the M2P does not have one it uses a rolling shutter.

Have you seen any recent research indicating that this is still pertinent? I believe most major post processing software now compensates for rolling shutter.

Though I totally agree that the M2P is not a serious mapping tool...

 

[dougcjohn]

Have you seen any recent research indicating that this is still pertinent? I believe most major post processing software now compensates for rolling shutter.

Though I totally agree that the M2P is not a serious mapping tool...

Software has greatly improved if not a mechanical, although it's not equivalent to mechanical simply by nature of capturing image between the two. The mechanical will provide better results.

If M2P isn't a good non-mechanical option, is that due to camera or platform? I don't think anything else in same category/class would make a significant difference.

 

[adm_geomatics]

Have you seen any recent research indicating that this is still pertinent? I believe most major post processing software now compensates for rolling shutter.

Though I totally agree that the M2P is not a serious mapping tool...

Yes - software algorithms have gotten "better" at compensating for rolling shutter but they have not eliminated it. A Phantom 4 Pro also has adjustable aperture and attitude mode and will always be better than anything with a rolling shutter as will a full frame be better than a Phantom 4 Pro. Rolling shutters are just inferior cameras and there's nothing that will change that. All this said the Mavic is just to small and for that simple fact does not handle the wind as well and is not as good for the type of mapping that we do. Maybe if you are doing projects less than 10 acres that allow you to fly lower then it would be ok.

 

[dougcjohn]

I'm more focused toward mechanical shutters as stated above for their benefits in both shutter & aperture. I don't consider the M2P stability as poor; their are several Ag multispectral sensors made for the M2P and used successfully for terrain, crop assessment, crop damage, etc which requires accuracy as well... although their support of Matrice 200 & 600 platforms are more prominent.

Although the OP's question was for a M2P PPk kit for small construction projects & company. The M2P's 1" sensor and adjustable aperture f2.8-5.6 isn't comparable to a P4P / X4S... for his intended usage, similar to many others, the M2P has been used successfully in mapping and 3D modeling. If there was a choice, a P4Pv2 would be a much better option, but until the P4Pv2 was brought back recently into production many went the Mavic route.

On a limited use, small projects, learning curve to assess what's needed in sUAV investments, I wouldn't rule a M2P out if already purchased. The orthos I've compared with an I2 X4S, aren't equal but still usable, and depending on the needs or minimal fees may be totally acceptable.

In the midwest from my discussions, several construction companies, Ag or Ag COOP aren't fully on-board with aerial services yet. It's a slow adoption and payback on investments may be low for many areas or services. Locally a large Amazon project was underway with Ryan Construction. Their interest was minimal in sUAV, although they did use a sUAV service for some preliminary work. On other Ryan projects in area, they expressed no interest beyond their pole mounted cameras. Some aerial progress photos & simple ortho were useful for their Client progress briefs but not of any value in their opinion.