Detect Bump in Laser Line

[shane5ab]

Hi Everyone,

I am working on a project where I am using a laser to detect number of bumps on the surface. Attached is a screen shot of the laser profile. Now I am running short of ideas, how should I detect if there are two bumps or three. 

I tried using find straight edges, It is giving me a few good results, but when I am using IMAQ Find Edge VI in LabVIEW to do this, I am not able to get anything but the points are plotted same as the original line.

Please see all the screen shots

Can anyone please help me to detect and count the number of bumps.

Kind Regards.

Shane5ab

[BruceAmmons · Accepted solution]

Here's an idea:

Use the rake function to find the first edge coordinates, from either top or bottom (top might work better).  Fit a line to these coordinates (removing outliers) and subtract the fit coordinates from the original coordinates.  Extract just the Y coordinates.  Use Find Peaks to find the bumps and count them.  Alternately, calculate the slope (1st derivative) or second derivative and locate the bumps using those graphs.

Bruce

[shane5ab]

Hi Bruce,

You are great. I used your method, and it all did the trick, Actually I had tried this rake function, but I did not know how to get it going any further. Thanks a Ton, You explained it perfectly.

Regards,

Shane5ab