Reach RS+ Tips?

Hello everyone,

I have some work lined up this week surveying a series of sites for a local council requiring 1-2 cm accuracy,

I am planning on using a Reach RS+ which has just been delivered with Drone deploys Business package and a Phantom 4 Pro V2, I’ve made a series of chequered GCPs with wood panels below to weigh them down, and have purchased a 2m telescopic GNSS survey pole, and I also have a hand held spirit level to make sure our pole is straight when recording points.

Does anyone who has any experience using a set up similar to this have any tips or tricks, or anything worth watching out for when putting all this together.

My plan is to export the the finalized model into a DXF format, insert it into Auto cad myself and make any changes required if some points do not align and if I need to add in any further GCPs into the model I can do here, I have seen recommendations to leave a 50 feet buffer between GCPs and the edge of the surveyed area, any have any recommendations here on how far GCPs should be apart from each other?, I will be numbering each one so when allocating the points I have a nice visual reference to use.

Hopefully all goes to plan, and if successful should lead to a lot more work, but assuring this runs smoothly is crucial to us at this moment in time, I hope someone else on here has some similar experiences,

Many thanks,
Kier

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Message me and we can setup a phone call.

Hi @Drone360Vision,

Below is a set of Support documents that could be helpful for you to learn the best practices when capturing and processing GCPs with DroneDeploy:

As for the distance between GCPs, I don’t have an exact distance to recommend as it mostly depends on the size and nature of your area of interest. Just take into account the following considerations:

  1. Make sure to use at least 4 or 5 GCPs per map. A minimum of 4 GCPs per map is required.
  2. Check that the GCPs are not very close to the boundaries of the maps. As you mentioned before, 50 ft away from the edges is recommended.
  3. Make sure that the targets are evenly distributed around the mapped area > As you move away from the GCP markers you start losing accuracy, that is why you want the targets evenly distributed throughout the map.
  4. Make sure to capture any changes in elevation when dispersing the targets throughout the map.
  5. Make sure to fly using high side and front overlap. Usually, between 70% and 80% are recommended.
  6. Last but not least, make sure that you are using an RTK GPS or an surveying method to read the GCP coordinates in the field and get accurate results. When non-RTK (or non-PPK) GPS is used you will consistently see an accuracy of above 3-10 meters.

I hope you find this information helpful. Happy mapping!
Andrea

Smartphones will soon provide 1-2 meter accuracy with the new Broadcom chip that uses L1+L5 GPS frequencies which benefit significantly from the higher-power, lower-frequency L5 signal to a provide faster, more stable lock. This new generation of phones, along with new, lower cost, sub-meter accurate GPS receivers based off this chip, will offer drone operators a much more cost effective and stable source of GPS coordinates for their GCP’s. Now all we need is for this technology to migrate to our drones for improvement in non-GCP’s senarios.

Regards,
Terry.

L1/L5 is actually sub-meter. Better than that with fixed RTK and/or PPK. L5 is a lower frequency, higher power signal that should have better signal-to-noise values which should allow for more stable fixes. I am betting that once the technology is vetted for industry use that dedicated devices will be made that may actually be less than phones, especially with current trends.

Doesn’t mean much to my company’s scenario, but it will help allot of people. Also, imagine lane-accurate GPS directions… No more being on the access road and maps thinking you’re on the highway.