DIY Laser levelling using webcam and laser level

[unromeo]

Hi Unromeo
Hi All

A mate and I have been mulling over using a Raspberry Pi and Joe's excellent software.
Actually a pair of Pi's to position an XY positioning system probably using an Arduino to automate the process of generating a rail mount. It will use a simple cutting head that "Pecks" the surface to be flattened using a small cutter head. it will only need a small motor and the cutting forces will be very light so no big deal. The completed surface will look a bit like a scraped surface. The cutter head will be mounted on the rails that will later be used in the machine being built, these will be mounted on a temporary mount.
Maybe we could collaborate?

I am planning to design the device in 3D CAD with a primary objective of Laser cutting as many of the parts as possible out of Steel.

This will keep the costs very low. I would make the mechanical s open source.

Regards
John

Hi John,

sure, if I can help with anything I will gladly do it, the only problem is that my programming kung fu is not that strong and that project was a while ago, but I can crawl my way into a working program if I want to. I can also assist in CAD and 3d printing if there is the need.

I wonder, if the measuring sensor is ofset from the pecking axis (the cutting head) won't that be an issue ?

I have a different idea how to measure the center of the laser line that won't involve cameras and PC's, but it will need to be tested for precision. I want to try something old school and very simple: analog electronics. Two small photodiodes placed aprox. 1mm apart (depending on the thickness of the laser line) so that each will catch the side of the line. Some op-amps to compare and amplify the signal and an analog microampmeter to display when we are at the exact center. Any difference in amplitude between the two photodiodes will be amplified and shown on the meter.
I have to buy a decent laser module and will test this out soon.

Regards,
Romeo

[devmonkey]

Hi John,

sure, if I can help with anything I will gladly do it, the only problem is that my programming kung fu is not that strong and that project was a while ago, but I can crawl my way into a working program if I want to. I can also assist in CAD and 3d printing if there is the need.

I wonder, if the measuring sensor is ofset from the pecking axis (the cutting head) won't that be an issue ?

I have a different idea how to measure the center of the laser line that won't involve cameras and PC's, but it will need to be tested for precision. I want to try something old school and very simple: analog electronics. Two small photodiodes placed aprox. 1mm apart (depending on the thickness of the laser line) so that each will catch the side of the line. Some op-amps to compare and amplify the signal and an analog microampmeter to display when we are at the exact center. Any difference in amplitude between the two photodiodes will be amplified and shown on the meter.
I have to buy a decent laser module and will test this out soon.

Regards,
Romeo

Just remember that there are no laser line generators that paint a straight line, for that you need a pentaprism which is v.expensive. So it depends what you are trying to do. I ultimately went to a taut wire system with the camera, worked very very well for me but I only used for straightening in 1D, a dot laser would have worked equally as well if you can mount it securely enough (which is extremely difficult). I used epoxy for generating the plane for the pair of rails to sit on.

Cheers, Joe