We were excited by Pix4D’s Chillon project (http://pix4d.com/chillon/) and decided to make our own 3D reconstruction attempt using our U[g]CS software, DJI Phantom + GoPro and, of course, Pix4Dmapper.
Now we want to share how we made 3D reconstruction of our office.
Pix4D has recommendations for different type of targets. For buildings they recommend to execute two flights around the building with different altitudes and camera angles:
(The image is taken from the Pix4D site)
For a small building it’s possible to take all shots in a single flight, but in most ground station software it’s hard to plan missions where two or more waypoints are located in the same position, but at different altitudes.
Using U[g]CS we can easily create such waypoints thanks to true 3D environment:
So we planned a single mission around our office with two rounds around the building. DJI Phantom 2 autopilot is limited to 16 waypoints, but in this case it wasn’t a problem because we set GoPro to take one shot every half a second.
This is how the mission for our Phantom looks like:
After a very short flight we have got 395 pictures. They were loaded into Pix4D projected and processed by point cloud building algorithm.
First of all, we were impressed by how precisely Pix4D has restored drone trajectory (first picture in this post). More accurately in comparison with GPS track.
And here is the result of point cloud visualization of our office made in Pix4D:
We have also 3D reconstructed another object close to our office — fuel tank station at the airfield:
3D point cloud animation is available for download here.
Taking into account fully automated processing workflow and our zero experience in 3D reconstructions, we think that achieved results are quite good. Next time we will try to get more accurate results by combining different drone trajectories, ground control points and processing modes in Pix4D.
Sincerely, U[g]CS team
Comments
Yes, we know that this is very important feature. If you can wait 1-2 weeks we will release UgCS 2.9 update 1 and here will be button "Camera trigger" for A2 and WKM.
In 2.9 there isn't possibility to test camera trigger on the ground.
Another Question,
I am using the A2 flight controller. I have the trigger for my camera set up on F2 port. Is there any way to test shoot the camera in UGCS before a flight?
Thanks again for your helpful insight into this great software
Hi Tom, thank you.
Yes, you should add GCPs in Pix4D and mark them in some number of images. UgCS knows nothing about GCPs.
Hello Alexey,
I know this thread is old but when you talk about using GCP. How do you record these points? Are you talking about adding them in PX4D?
Thanks for your great information on this truly exciting product!
In UgCS 2.9 you can use Photogrammetry tool for that (former AreaScan in previous UgCS versions). You have to draw area of interest only, UgCS will do rest.
I want to create a true 3D model of a mountain with Phantom 4 drone and Pix4D software. I am wondering if you have planned the mission with UgCS software by giving a study area and UgCS caculated everything or you planned the mission manually by adding waypoints one by one? Thank you in advance for your response.
Hi James,
Currently I have only photo sets for this power line. They are not geocoded, but you can process them using Pix4D discoverer.
I'll PM you a link.
Hey Alexey,
Great power line images. I was wondering if you would be able to share the 3d models with me. I am current graduate student working on automated power line analysis and doing 3D point cloud pixel wise labeling. I do not have this kind of data a the moment but if you are willing to share please let me know!!
Thanks
Hi Alvin,
Yes, UgCS saves coordinates in the telemetry, for all types of supported autopilots.
Hi Alexey, thanks very much for the information! I look forward to the next release!
Based on Pix4D's use of flights log from the Pixhawk, it looks like we will still be able to get very accurate data. When coupled with GCPs, the accuracy gets even better.
At this moment, there is no way to get flight log from the DJI Naza Mv2 flight controller. So if UgCS is able to provide this data, I'm sure other DJI users would be very excited with this.
Does the UgCS get the Lat/Long info in the telemetry from the aircraft GPS? Thanks!