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View Full Version : Sharing new usb camera positionning device



Marc F. Lupien
05-26-2016, 04:16 PM
Hi everyone,

I want to share the installation of a USB endoscope camera on my Desktop to aid in setting X,Y coordinates for my projects. Maybe some of this can be helpful to others.

I bought the camera here : http://www.banggood.com/Wholesale-5M-USB-Borescope-Endoscope-Waterproof-Inspection-Snake-Tube-Video-Camera-Lens-p-43623.html

The camera is easy to mount since it's a nice metalic cylinder. Look at the pictures to see how I mounted it. Some improvement possible there ;-)

After aligning it to be parallel to the router, I computed the offset from the router bit's center and createed a new custom script to move the CNC on the camera's position and zero X and Y there.
The only real special thing about this installation is that I wrote a small program to display the camera's image with a crosshair in the middle in order to use it to locate a specific position. I had difficulty finding an existing software so I wrote my own. It's basic but it works (the image is refreshed only once per second from the webcam). If anyone wants to get a copy of it (along with the source code), just email me at marclupien@hotmail.com.

From the first tests I managed to do, it seems to be precise +/- 0.1mm

Burkhardt
05-26-2016, 04:29 PM
Thanks Marc,
I have a similar camera (USB microscope) that I can attach to my machine. I don't use it normally because for most of my projects the x/y zero can be eye-balled in the middle of the blank and I try not to lose the zero while working on one part.

But here is where this proved to be very useful: for some high precision projects I needed to have my y-axis (gantry) absolutely perpendicular to x (very difficult to do precisely with a carpenter square or similar). I bought a large sheet of vellum with a 1/10" precision grid printed on it and taped it to the table so that the camera-cross-hair followed x when moving this axis. Then I measured how much my y-axis went off grid in the camera view from one end to the other (was about 0.03" for 31" movement) and corrected for this error. Helped a lot making accurate large cuts. I repeat this every couple of months to make sure it is still O.K.

Marc F. Lupien
05-26-2016, 05:38 PM
Thanks for sharing. It's always instructive to see how other use their Equipment.

bill.young
05-26-2016, 07:36 PM
Back in my boat building days we used to use a similar setup and the ShopBot Record functions to record key points and manually "digitize" paper boat plans. We would drive the tool around with the keypad and when we were over a point we would record that point. The way you recorded the point flagged that saved location as an endpoint, a point on a circle, node of a curve, etc.

It was pretty slow but scanning big paper plans was really expensive.

tri4sale
05-26-2016, 11:17 PM
I have similar camera sitting next to my 'bot just waiting for me to get around to hooking it up. Now I have a reason to get it hooked up and tested.