I am interested in making a 500 acre thermal map with the intention of locating abandon mine shafts. I would like to to know the best combination of equipment, process and software to create a complete thermal map of the entire acreage. I will be planning on renting the right equipment which have inspire and Matrice drones available as well as 13mm 640 resolution versions of the zenmuse xt and xtr cameras. Please let me know your thoughts on how to create this deliverable. Thanks for your time,
If I can help out please feel free to contact me!
It is indeed a very interesting project!
Here are some recommendations to optimize your future thermal processing:
* Regarding the camera itself:
- a minimum sensor resolution of 640x480. Smaller sensors are not supported and typically do not calibrate.
- the lens option we recommend is the 9mm since using a lens with a smaller focal length increases the image’s footprint, though it is possible to use longer lens focal lengths.
- to choose between Zenmuse XT and Zenmuse XTR , you should before determine which kind of data you wish to obtain: if you wish to compare relatively between each other the features in the area, Zenmuse XT with its relative temperature measurements might be sufficient however if you wish to measure the absolute temperature of the area, Zenmuse XTR with its radiometric calibration will enable you to measure such information.
* Regarding the image acquisition:
- Have very high overlap: 90% front and side image overlap.
- The images have been taken at a resolution of at least 640x480.
- The images do not suffer from motion blur. Thermal camera exposure times can be longer than a comparable RGB camera you should, therefore, adapt your speed to obtain sharp images.
- In case you are planning to use Pix4D Capture please check this article regarding the use of Zenmuse XT with Pix4D Capture and the support of XT and XTR cameras on Matrice 100, Inspire 1 drones in this article. As a side note please note that there is a known issue with (Inspire 1 with XT): the mission is flying very slow (less than 1 m/s).
* Regarding the flight plan and processing of very large projects:
- refer to this article to adopt the flight recommendations corresponding to your type of terrain.
- ensure to maintain constant overlap and GSD in between your flights (taking into account changes in terrain elevation).
- if possible, process the different flights in different projects and either merge them or assemble the outputs in a 3rd party software.
For more information on thermal processing with Pix4Dmapper, please have a look at this article.
I hope this helps,
Were you able to complete this project?