Another Octoprint plugin: line tracer

So what you’re saying is… The next time my wife needs a dozen shapes cut out for her classroom… I can just have her draw them onto a sheet of paper and my machine will cut them themselves?

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That’s the idea. Although right now it does only a single closed curve per job, so multiple shapes is still going to be multiple jobs.

It’s probably worth adding an SVG export feature too, so it can be used as just a scanner and skips the toolpath generation. All the options for pockets, stepover, finishing passes, holding tabs, etc, are probably too much to add, so SVG export probably makes sense for those, and for the simpler case of a plain single-contour cutout you can skip the CAM and have the plugin do it.

A couple months ago my daughter drew a ghost pirate robot on paper and I manually copied it into Inkscape to cut out a physical MDF copy. I didn’t do a trace operation. Instead, with the mouse I drew the same shape into Inkscape by hand, matching as close as I could. Then CAM with Estlcam, cut it out, and she painted it.

This was part of the inspiration, since the non-CAD origin is something of a hassle.

Oh and this is a girl ghost pirate robot, hence the rainbow dress.

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This is a great project! I love the implications of this. But is it sad that the feature That would motivate me the most to implement this almost immediately would be for an automatic XY homing for starting a cut. I would like to draw an “X” then jog into the area then click a home x y button and let it center the bit for me. Or better yet I could have that mark on my Z probe plate. Oh … I like that.

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Actually, this gives me an idea. Suppose there were an ‘arrow’ target made of tags, similar to the one in the video but it had a very long tail. Place the tip of the arrow where you want to go, and orient so that the tail of the arrow passes under the camera, within its field of view. Then click ‘go’ and it figures out where it needs to go and places the cutting bit precisely at the tip of the arrow. Boom!

That would be so awesome! Maybe not for homing per se, but for jogging in general, you can go from anywhere to anywhere with one click. That is better than any joystick or handwheel!

I love it, and now I can’t not do it. I will do that tomorrow. :smiley:

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Actually… this would work great for auto-homing.

It almost never fails when I do a multi-bit cut that I somehow bump or move the machine just enough to cause small imperfections with the second bit. If I didn’t have to worry about that, it’d make the process easier.

I could job the machine off the side of the work piece. Change bits. Tell it to find 0,0 on it’s own. Set Z height with the touch off plate and it’d be ready to go for the next pass.

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If you’re cutting a part out of new material, the first origin doesn’t have to be precise (just enough to keep the part in the workpiece). But the second bit (or a recovery job) need to have it exactly right.

Having a sticker that you can put to define the origin, home the machine to, and then be able to re-home to the sticker might be pretty nice. Does 3M make post it notes with AR tags yet?

This is just fun to try to think of what can be done.

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you can still print some aruco /charuco markers on printable sticker paper

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Dual mount a laser with the router. Let the laser burn the AR code. Then the router can Home to that.

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Oh, now that is thinking Outside of the box Jeffe

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I suppose you could hold a homing sticker under the camera and move it while the machine follows you. That could be how you jog the machine.

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You’re on HAD:

Someone very good looking must have tipped them off :sunglasses:

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YESSS!!! I hope this motivates you to keep messing with this. I am confident this has a ton of potential.

As it is I think it is extremely impressive and can already be put to work, I just think there might be a few hidden gems in there we aren’t taking advantage of currently.

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Nice! And thank you!

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Just came from HAD, and I love this. I have had an idea banging around in the back of my head for easing construction. Combined with a maslow cnc (or similar) a line tracing tool could make quick-ish work of accurate enough for construction (±1/8" or 3 mm) cutting drywall/plywood/whatever sheets.

Having read the article, I understand this isn’t that, and there is significant dev work to get from here to there, but it presents a solution for how to ease the toolchain to calculate the cuts.

Thank you for the inspiration.

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And there goes Ryan’s bandwidth for the day. :slight_smile:

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Well, if the camera were mounted on LR2 (which should be simple enough) then I think it could do exactly what you are describing, since that machine can do full 4x8 sheets. I’m interested, what are you seeing as the shortcoming?

It might be a bit overkill for big rectangles though, and it’s more intended for organic shapes that are a headache to get into CAD/CAM.

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When I’m doing construction, overkill is trying to hire and train a helper who can accurately measure and cut a piece of sheetrock with more than 1 outlet. If I can sharpie up a complex set of cutouts and throw it on a machine to CNC for me and let it do the work, I will know I have a good fit when it is done.

I wanted to point out that I had read the article and recognize the program as written is for closed blobs. Multiple sharpie lines either closed, or open to the edge on a 4x8 sheet is a different modeling problem. However, I really like the principle of surface line - openCV - CNC toolpath because ov the accessability of a pen and the common need for better cutting.

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Ah, got it. Thanks!

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Upping the plan now!

Who knew you made a different kind of digital apprentice! Pair that with a fairly portable full sheet CNC and boom, one guy can do the work of two.

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It looks like this project already includes openCV for calibration of a maslow: github - WebControlCNC

Perhaps this would be an easy-ish integration. I’ll have to dig in a little.

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