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Using Ebee RTK to collect high precision GCP's

Hi!

My question is.

Would it be possible to use Ebee RTK to collect ground control points?

Let’s say if the weather conditions are too demanding to fly the Ebee it could still be used on to collect GCP’s through VRS?

Obviously the positions would need to be corrected using Emotion software, but it would save in logistics and investing in survey equipment.  

In this case user could use multi rotor drone to collect the images and post process the data with GCP’s. 

Just an idea.

Have the Ebee attached to tripod and level it through Emotion.

Open the camera bay and set GCP marker on the ground and adjust it to middle of the camera view and take photo.

I don’t really know how the GNSS receiver and position has been set, but I’m sure it could be done.

Hehe

 

 

Hello Abkham,

In principle, this is a good idea; what you need to consider is the point in which the eBee is registering the coordinates and if this point coincides with the GCP you want to measure. If there is a shift between the coordinates and the point marked on the ground, this will impair the accuracy of the results.

Best regards,

 

I have spent nearly a week to try and figure out what is the best system to buy to get reasonably accurate GCPs, but it’s a real mind field to figure out what to buy and for what you can pay and what you get for that if your not a professional surveyor in the know.

We basically like to achieve around 1cm-2cm accuracy for the z axis which for volume cut and fill areas is the most critical for the majority of the work we do with Pix4D.  I see the RTK GNSS systems are obviously the most accurate in a short occupation time frame in the field but also the most expensive, where as others will do a reasonably good job with a static base stations, but having to have a longer occupation time frame. Even so the cost can vary from $1000 to $45000 when for the higher end cost it also includes special processing software.  Then the next issue is how some of the systems generate the data that then needs to be converted to use in Pix4D in some systems seem very complex or it needs other external paid services as well.

So where should one start and go from here?

Well firstly it would be good if Pix4D could set out a basic guild line chart of some recommendations similar to how they set out the recommendations for a PC to do the processing.

In the meantime and taking into account our preferred budget would be around $2000-$6000, can anyone please give some type of guidance and recommendations which system would be able to achive the type of this type of acuracy?  

John,

Take a look at this Base/Rover kit for $1,999 :

http://www.tersus-gnss.com/collections/gnss-rtk-boards/products/gnss-gps-rtk-receiver-kit-bx305-915mhz 

 

You can also read my RTK discussion here:

https://community.pix4d.com/t/4703-Discussion-on-RTK-GPS-Systems-#gsc.tab=0 

 

In my experience, the field work required to achieve 1-2 cm Model accuracy requires occupying each GCP at least twice with RTK GPS (best if at different times of the day), capture enough low altitude images for a ground sample distance near 8 mm, and use plenty of MTP’s.   

You can find a used Trimble or Topcon Professional unit under your $6,000 budget.  

 

Hello

Not certain this is the right place for this question, but I figure if there’s other eBee RTK users here, it may work out. 

I survey agricultural land to get elevation mapping. On one particular piece of land, part of the field (90 acres) was done with an eBee RTK. Another 550 acres was done with a non RTK eBee. 

The 550 acres surrounds the other 90 acres that was previously surveyed with the eBee RTK, and I need to correct the non RTK data, so that it is consistent with the more accurate, eBee RTK data. I have merged all the flights, and it shows all the points where photos were taken, and that all matches up and looks the way it should (it shows photos over the entire section of land that was surveyed). However, when I look at the DSM, that 90 acre piece shows up as poor results, or just non existent. 

What do I need to do to bring these together, and use the RTK surveyed piece to correct all the data for the section?

Thank you in advance

Troy

Bought this https://reachrs.emlid.com/ but have not tested it out yet. 

John, I hope you don’t mind me asking but what software are you using to calculate cut and fill?.