How about capturing a VERY
How about capturing a VERY short sample from the A/D port on the PIC and let the Etch-A-Sketch draw the curve like an oscilloscope. Or capture a longer sample and have a button to go one “page” forward/backward in the sampled data. It won’t be useful, but it will certainly have geek value.
Nah
Nah. I don’t care who can see where the donkey work is done. I only want to prove it to myself. Selfish? So sue me!
By the way, you made coffee come out my nose. Thanks for that!
thats pretty cool…
You should have it connect to a computer so you can upload images to it and have it make them. 
It is controlled by a PC
…or are you talking specifically of the upload of images?
Hmmm… I’d need some method of converting a raster image to a vector image.
I suppose I could do a simple edge finding routine, but how the heck would I convert that o vectors?
Hmmm…
a converter program
Its an application that finds the lines in the image then converts it. That would be cool.
Here is some info on it: http://www.masternewmedia.org/how_to_convert_bitmaps_into_vectors/
Manual task
You had my hopes up there. No it’s still a manual task. I know one chap who’s doing a PhD in the area and he says it can’t be done. Here’s an extract from the above web page:
Bitmap to vector conversion is a difficult, highly technical and time-consuming task. There is no program or utility which can vectorize the image you have into a perfect one because the software doesn’t know what you need.
This is why bitmap to vector conversion work requires dedicated time, patience and several trial and error sessions to fine tune the best procedure and workflow to adopt for your assignment.
But I’m not going to let a little problem like that hold me down. I have a plan. A cunning plan.
outsourcing?
Let others do the donkey work for you! Let the visitors of your website click on the perceived lines in your images. Akin to what the Giant White Glove Project did when trying to track a certain moving object in this video.
A thousand clicks a week would render a vector image in a , ehhm, week!
How hard is it
It can’t be that hard for raster pictures of line drawings (I know it’s only a subset of the full problem). A decade or more ago I used to configure and install document management systems. Engineering companies had loads of CAD drawings (made the old way with ink and rulers) that they wanted to use in their new AutoCAD workstations. We found a company in Phoenix that had built a box that you fed a scanned image of a drawing into and it produced a vector file for AutoCAD from the raster. It wasn’t perfect, but it was good enough for be a start for “as building” drawings. Company was called GTX. Box was expensive and big, but mainly because it contained a lot of custom hardware. I’m sure a GPU does all this and more nowadays.
Mike
Nicely done!
What computer language do you program in. I know you do assembly. I want to learn RISC assembly for hardware programming.
Can you vector a computer graphic yet?
Explain
You name it. I program in a lot of languages. Some which have never been heard of outside the aviation industry. For control applications I use Visual Basic or LabVIEW. I have to say I’m not enjoying all this .NET crap. Making all computer languages plain old scripting tools when the interesting, fun stuff is all done by Microsoft at a lower level really pisses me off.
“vector a computer graphic”? van R is a vector display. It renders a computer graphic. I don’t see what you mean. The PIC renders the straight line itself in RISC assembler using a Bresenham algorithm. I may try to get it to render a curve next.
That’s great Rik !Air
That’s great Rik !
Air traffic controllers could save a bundle by outsourcing the data processing in a similiar fasion - of course I’d be scared as hell to get near any plane…
hilarious !
Hi BOA,Fabulous project,
Hi BOA,
Fabulous project, you’re all artist !
How fast can you drive the steppers? Have you found the limit already? Just curious, I would find an odd bit of satisfaction seeing an automated etch-a-sketch drawing faster than a printer…
Me too
Sadly, I would derive the same satisfaction. Except, I don’t find that odd! Perhaps this was a comment on how people other than yourself would find your mentality? I don’t find it odd ion the slightest!!
Ummm. the answer is that it takes a good 5 secons in a straight line from one side of teh EAS to the other. Bear in mind, also that this is a POCKET Etch-A-Sketch, so the screen is only about 3" wide!
I’ve only use $20 steppers, so their torque is pretty crappy and I have driven them the “easy” way. The proper way (as pointed out above) is to overdrive them, then reduce the current as the stepper settles. I need about 10ms step time, which ro 7.5deg step is nearly half a second for a full rotation AND I have a 4:1 reduction gear in place to increase torque.
Very funny
Lovin’ that last link!
Currency Exchange
Isn’t a million yen like 10 USD? a million pounds is like 4 million dollars…