 # Surface roughness

Hi

I’m working on a geometry which is a surface with a manual roughness.

I want to compare the surface roughness of this geometry with another one with more roughness.

I have already tried working with Bison plugin. However, the left geometry which is smoother, shows a higher surface roughness. ( I might have made a mistake though because it doesn’t make sense)

How can I measure the surface roughness? For example, a surface roughness of 18%.
Is this possible?

It depends on how you define roughness. For instance, you can take the reference mesh faces centroids (The flat Mesh) and compute the mass addition of distances from the modified mesh faces centroids (Rough mesh). In this case, you can say the more the mass addition number, the higher the roughness is.
Another way of defining the roughness is to compute the distance of furthest centroid for each geometry and attribute the roughness to that number.

I did an initial try on the first method you mentioned. I had another approach though, but the results would be the same. So I will continue with that and try this approach as well.

For the second approach, do you mean to assign only the distance of the furthest centroid to the roughness?

So there isn’t a way to define the roughness as a percentage? Of course the first approach can be used at the end, but the roughness becomes somewhat relative. However, if I can extract a number for percentage, it gives a more clear idea.

If you want to define percentage, you have to assign the max and min of roughness. Then you can use the first method and divide the max value of rougness to the mass addition number.

Yeah exactly, it can be divided by a certain number for max and min of roughness.
Then I will continue working on this.

Thanks!