How can I calculate the normal vectors for each point on a curved surface?

Hello,

I want to calculate the normal vectors for each point on a curved surface. I tried surfnorm, but my data does not have the correct input for surfnorm. I have an STL file with a surface and the x, y and z coordinates for all points. I want to have the normal vector for all points, so I can select the points I am interested in, using the x, y and z coordinates. In the zip file I attached an example image of the surface and an example of the STL file.

Does anyone have an idea how I can use surfnorm or which other options there are to do this? Thank you!

Answer 1

[KSSV]

Check this file exchange: https://in.mathworks.com/matlabcentral/fileexchange/22409-stl-file-reader?focused=5193625&tab=function This function reads the stl file and also it calculates the normal vectors.