fitting a cylinder to point cloud of tree and then finding v

[jeniasingh]

Dear Sir,
I have a point cloud of tree i want to fit a cylinder to it and also after that i need to calculate it's volume. please help me how can i do it.

[daniel]

Hi,

the only way to fit a cylinder today in CC is to use the 'qRansacSD' plugin (SD = shape detection).

You should use the latest release (2.6.0) as this plugin dialog is much clearer now.

Once get your cylinder (be sure to uncheck all other entities!) you simply read out it's height and radius to deduce the volume.

[jeniasingh]

Thank you sir for your reply.
But when I am fitting a cylinder to tree point cloud it is fitting cylinder to the whole point cloud. i want to fit a cylinder at a height of 1.37 m and then want to know it,s radius.please help.

[daniel]

You could segment the cloud (with the scissors tool) so as to keep only the points on which you want to fit the cylinder?

[jeniasingh]

Thank you sir it helped.
how can i achieve slicing of the point cloud data at different heights like starting from 0m to 1.37m then 1.37m to 4m and so on.

[daniel]

You can use the 'Cross section' tool (with the 'multiple slice' generation option where you define a first section box that is repeated in one or several dimensions).

[Amaljith]

Hi sir,
I have the point cloud data of a cylinder from ID side in .e57 format. I have the original diameter of the cylinder. So I want to check for any diameter changes. Is it possible in CC?
Please help if its possible. Thank you in advance.

[daniel]

Well, you can create a cylinder entity (with the right radius). And then roughly align it with you cloud (manually). And eventually align it finely with the ICP registration tool. This will give you the difference to your theoretical cylinder/radius.

Otherwise you can use the Ransac Shape Detection plugin to fit a cylinder.