Cave surveying with LIDAR

[Mike Lake]

Yes meshlab.  I had quite a few spelling errors in my post.

CloudCompare from https://www.danielgm.net/cc/ seems to be actively 
maintained.
I have not had to stitch together data myself though.
I have found a laptop with a GPU is pretty essential. Without a GPU is 
just soooo slooow.

I would think registration markers would be useful. If end up not 
needing them that's fine, but if you do the scans and subsequently can't 
quite merge them together you might need those exact registration 
markers. Are you going to survey to them with a DistoX or does the 
BLK360 do that? It does look a very nice unit. Probably a lot of $$. 
Hopefully it comes with some good software to do what you need.

Mike

---
Mike Lake

On 2019-11-13 21:51, Jeskynar wrote:
> Thanks!  I'm looking into how I might stitch together multiple scans
> from a BLK360 lidar scanner to produce a decent cave survey.
> I guess the problems are: 1) how best to perform the scans, where to
> position the scanner, whether to use registration markers
> 2) how to stitch together the resulting scans, 3) how to clean up the
> data, 4) how to build a useful model
> 
> I guess you mean meshlab not meshlan? meshlab seems to have been
> untouched for a few years now.
> I'll have a look at cloudcompare. I've got access to autodek recap pro
> but I'm not liking it so far.
> 
> Andrew
> 
> On Wed, 13 Nov 2019 at 09:53, Mike Lake <mikel at speleonics.com.au>
> wrote:
> 
>> Hi Andrew
>> 
>> I have surveyed caves with a Zebedee quite a few years ago, before
>> it
>> was commercially available. Probably several kms of passage. That
>> doesn't give me an expertise it it though :-) I use Meshlan and
>> CloudCompare to view and manipulate the point cloud data.
>> 
>> This youtube video if of the Cliefden Main Cave Survey using the
>> Zebedee
>> https://youtu.be/o7otVG2cKD4 [1]
>> The data in here is downsampled quite a lot but still shows cars
>> and
>> trees on the surface. The cars on the surface just under the big
>> tree
>> gives a bit of scale.
>> 
>> Also surveyed a few other caves at Cliefden and at Wombeyan
>> surveyed the
>> entrance of Victoria Arch, and Wollondilly and Junction Caves. Also
>> 
>> surveyed a quarry on the surface at Wombeyan Caves.
>> 
>> What did you want to know?
>> 
>> ---
>> Mike
>> 
>> On 2019-11-13 00:31, Jeskynar wrote:
>>> Hi
>>> 
>>> Does anyone here have experience with surveying caves using
>> LIDAR?
>>> 
>>> Andrew
>> 
>> --
>> Cave-Surveying
>> https://lists.survex.com/mailman/listinfo/cave-surveying [2]
> 
> 
> Links:
> ------
> [1] https://youtu.be/o7otVG2cKD4
> [2] https://lists.survex.com/mailman/listinfo/cave-surveying