Friday, 22 September 2017

They might be giants

So, here's the first example of one of our Sequoia sempervirens TLS data. To say I'm excited would be somewhat of an understatement. No one has seen these trees like this before, and there will be so many things to look at from these data. The data are just stunning, and this doesn't do data to them but still .....
I get a cricked neck just looking at this!
The tree is ~80 m tall, and 16 m across the crown. Phil generated a first estimate of the volume which suggests it's ~80 m3, meaning it weighs about 40 tons! And 50% of that volume is in the lower 20 m of the trunk, perhaps unsurprisingly given its shape.

Meanwhile, here's a great example of Dave's 14 GoPro 360 photo setup.
Can't say we look good, but the trees certainly do. Remember, never go full lumberjack Andy.

Dave developed his Terrestrial Recording of 3D 360 Surveys (TR33S) system under funding he was awarded through the Universities Space Research Association (USRA - Columbia, Maryland) Internal Research & Development Program. The TR33S collects pictures in every direction by linking the 14 cameras together. The 360 photos are great, but more generally Dave is aiming to capture 3D point clouds using structure-from-motion (SfM). SfM is a photogrammetric technique that can model a 3D space from 2D images. It's widely used for UAVs but this is the first time I've seen it used like this, and there are some potentially great applications in forest research like this! Dave has written about his work with the camera on the NASA blogs: Below the Mangrove Canopy; and Mangrove Carbon With a Grain of Salt.