Jonathan Byrne

Stuff and things about Jonathan Byrne

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May 14, 2015

Aerial Mapping

I work in the Urban modelling group. They generate millimeter accurate 3D maps of Dublin using lidar scanners attached to light aircraft:

While the results are amazing, it is very costly to obtain this data.

Low cost unmanned aerial vehicles (UAV) have made it easy to obtain aerial footage. Combining the images using Structure From Motion (SFM) software enables us to create detailed 3D models. I am researching ways to improve the quality of the model and how to use video footage for dense reconstructions.

Here is an example of a 3D reconstruction of the Magazine Fort in Phoenix park. The footage was obtained using an unstabilised QX350 quadcopter. The camera used was a Gopro Hero+. The camera has a wide field of view which captures a greater area but also causes radial distortion of the images.

 

I then used VisualSFM to reconstruct the images into a 3D model. Despite only covering a single angle and generating a highly distorted image. The results were impressive:

I am now carrying out research in the artificial sky in UCD to work out the optimal scanning path:

Here is a reconstruction of 1/200 scale model of Cork Street. It is still quite lumpy but it shows the power of this approach. A scan of this area could be carried out by a UAV in less than 15 minutes.

Update:

Now after a bit more practice the results have improved significantly. HEre are some scan I carried out for the Archaeology department and the OPW.