Slashdot Mirror


Build Your Own Electric Etch-A-Sketch

mhaisley writes "Ok, case mods are cool, monitor mods are nifty... but an Electric Etch-a-Sketch beats either. Students at Cornell University built an electronically controlled etch-a-sketch, controllable by a PC mouse. This was part of a group of class final projects featured by their instructor."

104 comments

  1. COOOOL by KI4BBO.org · · Score: 0, Redundant

    wow, that is super cool! :) Sounds like fun... some cool tech.

    --


    _____
    Josh Powell - www.ki4bbo.org
    1. Re:COOOOL by Anonymous Coward · · Score: 0

      Can you please enlighten my on what is so super cool about it that warrants a story on Slashdot?

      It is neither of any use nor is it an incredible engineering feat.

    2. Re:COOOOL by nkh · · Score: 1, Flamebait

      Worst. Comment. Ever.

    3. Re:COOOOL by UniverseIsADoughnut · · Score: 2, Informative

      When I took a class on controls a few years ago there was a class project you had to do, build something that you would control. Could be anything. One of the things the prof wouldn't let us do is this. It had been done so many times before and had a couple etch-a-sketches sitting in the cabinent with motors allready on them.

      This is something students have probably done for such projects for 15 years.

  2. Reminds me of those EtchASketch tech support calls by AliasTheRoot · · Score: 4, Funny

    User: My Etch A Sketch has crashed what should I do?
    Support: Shake it.

  3. Re:Reminds me of those EtchASketch tech support ca by KI4BBO.org · · Score: 0, Redundant

    LOL.. that is funny I would encourage all to check out that page, there are some awesome pictures... :)

    --


    _____
    Josh Powell - www.ki4bbo.org
  4. Ethical? by Anonymous Coward · · Score: 0

    My software development ethics:

    - I receive a pay check on a timely basis.

    Looks good! Let's code!

    1. Re:Ethical? by Old+Telco+Guy · · Score: 1

      Is it just me, or does anyone else find it deeply impressive that Cornell University addresses ethics with regard to science/engineering? In a world where so many geeks just build anything they're tasked with building, it's nice to know that there are some classic academics, educators, scientists and students up in Ithaca who give a damn about this world and their impact on it.

    2. Re:Ethical? by another_henry · · Score: 1

      Often, geeks are they only people qualified to decise whether something should be built. Witness the recent retardedness in the UK about nanotechnology after Prince Charles said a bunch of bullshit about it.

      --
      "Studies have shown that people who eat peanuts live longer than those who do not eat."
  5. Re:Reminds me of those EtchASketch tech support ca by Kjuib · · Score: 1, Interesting

    After a while the lines start to stick a little, and you get the old faded lines all over the screen. This reminds me of the old monitors that the image got burned in. Do you think they fixed this problem?

    --
    - Your stupidity got you into this mess, why can't it get you out? -Will Rogers
  6. Has been done before by GarbanzoBean · · Score: 5, Funny

    It is called photoshop.

    1. Re:Has been done before by kinema · · Score: 2, Insightful

      You must be new here or your post would have refered to the GIMP.

    2. Re:Has been done before by kyknos.org · · Score: 1

      You shall never compare Photoshop and the Gimp

      --

      SHE does throw dice.
    3. Re:Has been done before by Orick · · Score: 1


      Photoshop is too complicated to count.

      "Paint" is probably more like an etch-a-sketch.

      --
      Kirby Reviews

    4. Re:Has been done before by Queer+Boy · · Score: 1
      or your post would have refered to the GIMP.

      Yeah, 'cause that's actually a lot closerr to an Etch-A-Sketch, at least in terms of functionality. ;-)

      --
      Not since Marie-Antoinette played milkmaid has looking simple and honest been so fake and complicated.
  7. wow... by nuggetman · · Score: 5, Funny

    maybe now i could actually draw a circle on the freaking thing

    i always saw kids in the commercials w/ these elaborate trucks drawn, i couldn't even make a damn circle

    not that im bitter...

    --
    ...and that's all there is to it.
    1. Re:wow... by Anonymous Coward · · Score: 4, Funny

      "i couldn't even make a damn circle"

      It's quite easy. You simply rotate the knobs either clockwise or counter-clockwise depending on whether the sine wave sample is above the x axis or below it and at a speed indicated by the value of the y axis. Obviously, the x axis represents time.

      The only tricky part is remembering that the left and right knobs aren't ever at the same point in the sine wave so you have to remember that your left hand and right hand might be moving in different directions and at different speeds. At first I founnd that it helped to use a precalculated lookup table but now I can just do the trig calculations on the fly.

      Hope that helps!

    2. Re:wow... by n17ikh · · Score: 1

      Glad to see I'm not the only one who can't use an etch-a-sketch. However, in my doctor's office (his personal office, inside the doctor's office you go to to see the doctor... Yeah, the English language is dumb), he has an etch-a-sketch with a wonderful, perfect landscape drawn on it. I asked him about it and he said a guy had drawn it while in the waiting room. Now, that either tells me the guy was extremely talented, or that waiting times for the doctor are just getting longer and longer....

      --
      Hard work pays off tomorrow, but procrastination pays off NOW!
  8. Fractals are where its at... by frostbane · · Score: 5, Interesting

    I think they should just drop the mouse, hook it up to a computer and draw fractals. That would be a really cool project and it would make some pretty cool results.

    1. Re:Fractals are where its at... by SamBeckett · · Score: 1

      RTFA - original design was based on a computer controlled Etch a Sketch. They modified the design to eliminate the computer.

  9. Not even Photoshop by LeahofRivendell · · Score: 1

    Photoshop had color!

  10. Cool? by Anonymous Coward · · Score: 0

    No, not cool.

    1. Re:Cool? by KI4BBO.org · · Score: 1

      yes it is cool :) I mean you try to make something like that, think of the programing that went into turning the motors just the right amount in just the right direction.. I am sure you couldn't even make anything half as cool as that :)

      --


      _____
      Josh Powell - www.ki4bbo.org
    2. Re:Cool? by KI4BBO.org · · Score: 1

      If its "very simple" then I would love to see you make one... I still think its neat :)

      --


      _____
      Josh Powell - www.ki4bbo.org
  11. Wouldn't it be cool by LeahofRivendell · · Score: 5, Interesting

    If you could use the expandable shapes like the circles and rectangles and stuff in most paint programs and the machine would just make it?

    1. Re:Wouldn't it be cool by asoko · · Score: 2, Interesting

      Or make the stylus continuously oscillate diagonally about the current position, so you could make calligraphy-style brush strokes.

  12. Re:Reminds me of those EtchASketch tech support ca by asoko · · Score: 1

    They should add another motor that shakes it and connect that to a "reset" button.

  13. The cheapest item on the BOM would be ... by syrinje · · Score: 3, Interesting

    ...the Etch-a-Sketch itself (yeah, yeah, I know they got it for free but you could source one for a dollar). I am impressed with this project as a teaching aid. Combines a whole lot slew of concepts in one fun project! So what if it isnt practical - technlogia gratia artis.

    --
    See that long UID - that's what you get for lurking too long
  14. Forget the etch a sketch. STM project by mpn14tech · · Score: 5, Interesting

    A class a few years earlier built an scanning tunneling microscope. http://instruct1.cit.cornell.edu/courses/ee476/Fin alProjects/s2002/sm242/index.htm

    1. Re:Forget the etch a sketch. STM project by parkanoid · · Score: 2, Interesting

      STMs are commonly built by hobbyists out of commodity parts. Nothing unusual. I have a half-finished one sitting on my desk right now (still missing the piezo elements, mostly due to laziness).

      Then again, the EAS project is pretty simple either, just a pair of stepper motors. Cool, but what michael (why the fuck is that moron still allowed to post anything? seriously) described sounds more like an electron beam magnetizing the screen selectively.

  15. Old mouse designs/upsidedown etch-asketch by acomj · · Score: 1

    I have an old mouse with instead of a ball it it had two "paddles" like the contols of an etch-a-sketch. It worked ok, but the ball worked much better.

    Now its has come full circle and you can use a ball mouse to the 2 paddles..

  16. It's just a plotter... by Anonymous Coward · · Score: 0

    X-Y device with a nib on the end, albeit with no way to life the nib from the screen. Sounds a lot like a plotter (which incidentally I haven't seen for years).

    Does anybody still make/use them?

    1. Re:It's just a plotter... by I+don't+want+to+spen · · Score: 1
      I believe many terrorist organisations use plotters. Oh, you mean the drawing ones ...

      Sorry, it just reminded me of the English rhyme about Guy Fawkes attempting to blow up parliament:
      Remember, remember the Fifth of November
      Gunpowder, treason and plot.

      --
      Don't go to a brothel if you want to buy broth
  17. If only... by Anonymous Coward · · Score: 1, Funny

    They could hook the thing up to my video card and have it redraw 60 times a second, I'd have a cheap monitor!

    1. Re:If only... by hsoft · · Score: 1

      Maybe it could work, but you would have a lot of smoke. Besides, you would *constantly* have to shake your monitor for it to reset the picture.

      --
      perception is reality
  18. Re:Final Year Project?!? by LeahofRivendell · · Score: 1

    My "friend" who went to a community college built an LED display that just counts in binary for his FYP....Pathetic

  19. html guide by Anonymous Coward · · Score: 0

    html guide

  20. GIF2EAS by ElDuderino44137 · · Score: 2, Interesting

    Hey There,

    What the needed to do was ...
    supply a image as input ...
    and have the thing ...

    A) Translate it to b&w
    B) Have the EAS automatically draw it

    Kind of like the novelty of ...
    translating an image to ...
    ascii ;)

    Cheers,
    --The Dude

    1. Re:GIF2EAS by Anonymous Coward · · Score: 0

      Your cell phone...
      has no word...
      wrap.

  21. The original plotter by jklein · · Score: 1

    I don't have any references, but I remember hearing that the very first computer controlled plotter was made from an Etch-A-Sketch.

    1. Re:The original plotter by Animats · · Score: 3, Informative
      No, the first computer controlled plotter was made from an analog X/Y pen recorder. The analog computer for the Nike missile launch system had one, as did the Atlas missile guidance computer.

      There was the Iconarama, which was an Etch-A-Sketch like device attached to a projector. This was the first large-screen computer controlled display, and was used by NORAD in the 1950s. The device scratched transparent areas onto a slide, projecting icons (usually aircraft tracks) on a screen. When the screen became too cluttered, a slide changer loaded a new blank slide. Two complete systems aimed at the same screen were used, to avoid a blank period during slide change and redraw and to provide redundancy.

      The Iconarama was one of a long series of early military attempts to build large-screen displays. There were wall-sized plotters. CRT/film/photo processor/projector combinations. The Eidophor oil-film projector.

      Eidophor technology first appeared in 1943, and there are still a few units in use. No other technology until DLP could reach the 4000 lumen light level of an Eidophor unit.

    2. Re:The original plotter by Nefarious+Wheel · · Score: 1

      I saw an article on making a plotter from an etch-a-sketch in the mid-70's. I don't remember the magazine but it was definitely in the Altair-kit era.

      --
      Do not mock my vision of impractical footwear
  22. Sorry, but this has been done before... by feloneous+cat · · Score: 0, Troll

    Us old timers remember that this was featured in an article WAAAY back in the print and ink mags (BYTE? Dr. Dobbs? Brain gets old after a while). They also hooked up a computer to an etch-a-sketch.

    Way to go, kids, you re-invented the fucking wheel!!!

    --
    IANAL, but I've seen actors play them on TV
    1. Re:Sorry, but this has been done before... by Feanturi · · Score: 1

      Way to go, kids, you re-invented the fucking wheel!!!

      And good for them. You are saying that everything done by one generation is -- done -- and nobody in the future should try it also? Besides, reinventing the (insert interesting invention here) is very educational.

    2. Re:Sorry, but this has been done before... by Anonymous Coward · · Score: 0

      Totally! I think it was DDJ, maybe 10-15 years ago before DDJ turned into a mainstream weenie magazine. Very neat hack at the time but come ON, try to think of something new!

    3. Re:Sorry, but this has been done before... by azpcox · · Score: 1

      Ah, no. They removed the computer from the picture and hooked up simply a mouse. Yes, there is an MCU for driving the motors, but it is a very good project for figuring out timings/electrical interfaces.

      It was funny to read about how they discovered the "Phenomon" that if you continually turn an Etch-A-Sketch knob in one direction, it never actually stops. Something every kid figures out right away. They used this "Feature" for reseting the stylus in the center of the screen.

      --
      What exactly do you mean by "Don't touch this button?"
    4. Re:Sorry, but this has been done before... by hlh_nospam · · Score: 1

      I recall seeing this around 1977 in Byte Magazine. I was on a graphics project for a military contractor at the time, and we submitted this to my supervisor as a joke. He thought it was funny, but *his* boss didn't...

    5. Re:Sorry, but this has been done before... by Kwantus · · Score: 1

      Creative Computing maybe? I remember the pix ... seems to me the sample plot was a parabola =p

    6. Re:Sorry, but this has been done before... by feloneous+cat · · Score: 1

      No. The point of education is NOT to re-invent, but to build upon what came before.

      Reinventing is merely another form of rote. That isn't learning, that is merely the act of repetition.

      --
      IANAL, but I've seen actors play them on TV
    7. Re:Sorry, but this has been done before... by Feanturi · · Score: 1

      Reinventing is merely another form of rote. That isn't learning, that is merely the act of repetition.

      Only the physical result is the repetition. The work in reinventing is entirely original within the mind(s) of those undertaking it. It is not even vaguely related to rote-learning.

  23. Re:Reminds me of those EtchASketch tech support ca by p0 · · Score: 1

    User: My Etch A Sketch has crashed what should I do?
    Support: Shake it.

    * pause * rattle *

    User: That didnt fix it. I think I spoiled my Etch A Sketch for good!
    Support: May I have your name sir?
    User: Al Gore
    Support: Have a nice day! Bye!

    * click *

    --
    This is my sig. There are thousands more, but this one is mine.
  24. Now this is... by Biogenesis · · Score: 1

    ...what I read slashdot for. Here's an interesting project that will hopefully cause ideas to spring up in my head but most importantly will encourage me to actually get off my ass and do something like this.

    I once thought about building a plotter with a mate of mine, maybe I'll bring the idea back up again...

    1. Re:Now this is... by DudeG · · Score: 1
      I once thought about building a plotter with a mate of mine

      You sure your mate doesn't mind being used as a hardware component?

      ;-)

  25. Re:Final Year Project?!? by castlec · · Score: 2, Funny

    Well.... In the poor guy's defense, I know I couldn't have built an LED that counted in binary at the end of my second year of school. I assume that his community college only counts to 10 like most others.

    --
    When I tell an object to delete this, am I killing it or telling it to kill me?
  26. It's missing a way to erase it... by seanadams.com · · Score: 3, Informative

    I built one of these years ago... the thing mine had that theirs is missing is some way to flip it over to erase it.

    I used a big servo (made for a remote controlled boat) to flip it over. Also a solenoid to lock the screen in the vertical position so that the servo/solenoid only need to be energized while the screen is being shaken.

  27. Re:Old mouse/COMP designs - Full Circle by shubert1966 · · Score: 1

    I thought the idea was great, if they could work a large wooden beaver into the design.

    No really, if they could build some mouse-jigs they could use the modified Electr-O-Sketch to design loom components. Soon they'd innovate Punchcards, then the Difference Engine - and finally the mouse.

    With recent advances in transistors and microprocessors they'd soon be able to design childrens toys without the need of the highly inefficient clay tablet

    I predict a bright future for this group of stalwart free thinkers!

    --
    Stuff that matters.
  28. A system admin's dream item... by thewiz · · Score: 1

    A working electronically controlled EAS may be a product that people would want to buy.....

    I'd want to buy one for every Pointy-Haired Boss I've had to help with their computer...

    --
    If "disco" means "I learn" in Latin, does "discothèque" mean "I learn technology"?
  29. Re:Reminds me of those EtchASketch tech support ca by AndroidCat · · Score: 1

    A pen up/down control would be nice. Do they make D size Etch-A-Scketches?

    --
    One line blog. I hear that they're called Twitters now.
  30. Re:Old mouse/COMP designs - Full Circle by Anonymous Coward · · Score: 0

    Pretty soon they'll invent the CaveComp plotter to automate those tedious cave drawings. :)

  31. Re:Final Year Project?!? by AndroidCat · · Score: 2, Insightful

    An LED that counts in binary isn't hard -- if you use a flasher LED: 0 1 0 1 0 ...

    --
    One line blog. I hear that they're called Twitters now.
  32. Re:Final Year Project?!? by Anonymous Coward · · Score: 0

    Not much of a count, then ...

  33. Direct X support? by adeyadey · · Score: 2, Funny

    Imagine, a 3d engine which can render 20 polygons a minute!

    --
    "You lied to me! There is a Swansea!"
  34. the art of motion control by xbryanx · · Score: 3, Informative

    I think the most interesting thing here is the wide range of projects of their class page and how they have come up with inventive ways of using microcontrollers (sure some of them aren't new but that doesn't mean they aren't cool work for a class of students).

    But if you think this is cool then you should check out the work of Bruce Shapiro. He's got a stepper motor controlled Etch a Sketch, but that's only the begining. How about a home built two axis plasma cutter, or a an old dental mill that turns 2d pictures into 3d sculptures.

    --
    Sin lies only in hurting other people unnecessarily. All other sins are invented nonsense. - Robert A. Heinlein
  35. Imagine a... by Anonymous Coward · · Score: 0

    .. monkey in a bucket!

  36. Before their time by Anonymous Coward · · Score: 0

    This was done a Loooong time ago. I think it was in the Circuit Cellar column in Byte magazine around 1980 +/- a few years. They put stepper motors on the knobs and could create graphs of much higher resolution than the monitors of the day. It may well have been before these guys were born, but that doesn't make their effort less interesting - it's still cool and innovative (assuming they independently thought of it). For a real experiment, they should try to patent it and we could then turn up the ancient prior art :-)

    1. Re:Before their time by BACbKA · · Score: 1

      Is it patentable once they put the know-how into the public domain by publishing on the website (prior art aside)?

      --

      VKh

  37. Re:The cheapest item on the BOM would be ... by Descartes · · Score: 1

    technologia gratia artis
    Technology for the sake of art huh? What like a printer?

    I think you mean 'technologia gratia technologiae' technology for technology's sake.

    Off topic! Ha, I wrote this on an etch-a-sketch!

  38. And yet... by Anonymous Coward · · Score: 3, Interesting

    ... articles about nifty microcontroller projects like the laser-based Iridium flare tracker get rejected. Go figure.

  39. Not Quite Original by Tellalian · · Score: 1

    Not to rain on anyone's parade, but this isn't exactly novel or complicated. Many undergrad engineering programs have a similar project. For instance, the University of Delaware (my school) assigned such a project as part of a sophomore level course in microprocessors. And that was two years ago.

  40. A bit underwhelming.... by Ellis+D.+Tripp · · Score: 3, Informative

    Is that all there is to it? A mouse moving the stylus of an etch-a-sketch? Now if it incorporated a "drag and drop" or "selective erase" feature, it might be interesting. As it is, this would make a neat high school science fair project, but a final project for an EE degree?

    Why was a microcontroller even NEEDED here? Rewiring the mouse to provide the raw X and Y encoder wheel pulses, and applying them right to the stepper drivers would give substantially the same results without the MCU and all the programming. If the stepper drivers need step and direction signals rather than quadrature pulse trains, run the encoder signals through one of the LSI/CSI encoder interface chips to get whatever you want without writing code or burning it onto a chip. A programmable solution for something this simple seems like complexity for complexity's sake...

    --
    Remember "News for Nerds, Stuff that Matters"? Help make it a reality again! http://soylentnews.org
    1. Re:A bit underwhelming.... by JamesUD · · Score: 1

      Have to agree. This E-EAS project is done in our sophomore microcontroller course (the last of four projects). Granted we did not use a mouse but I am sure some students could have rigged one up in the time alloted.

      --
      There are two types of people in this world, those with loaded guns, and those who dig. You dig. 001010011 001110101 00
    2. Re:A bit underwhelming.... by iantri · · Score: 1
      As it is, this would make a neat high school science fair project,
      The students at your high school must have been unusually bright..
    3. Re:A bit underwhelming.... by thepr0fess0r · · Score: 1

      I think in this case a microcontroller was needed... what are the odds that the pulse train coming from your mouse, given the deg/step of the steppers is adequate for turning those dials in a manner that makes for an easy to operate etch-a-sketch? More likely, some sort of scaling (read: counting) needs to take place, which the microcontroller probably handles nicely.

  41. Re:Final Year Project?!? by tilmanb · · Score: 0

    We just did a 4 bit multiplier using 3 PLDs. And this is in our second year (of 4). AND this is required for all students of computing science at our university (oldenburg/northern germany).

    --
    cd pub; more beer
  42. Careful... Ohio Arts May Sue by Anonymous Coward · · Score: 0

    If what happened with Alan Watts' Web-A-Sketch is any indication, Ohio Arts, the makers of Etch-A-Sketch, will offer $500 for the stepper motor design and web site, and if their offer is rejected, will threaten to sue.

  43. Electric-Etch-A-Sketch? by Anonymous Coward · · Score: 0

    I thought they were called Macs?

    (ba-dum-dum-ching)

  44. Re:The cheapest item on the BOM would be ... by Anonymous Coward · · Score: 0

    Wow, missing the point has reached a new high: understanding the language, recognizing the reference and STILL NOT GETTING IT.

  45. Re:Department of Redundancy Department by Anonymous Coward · · Score: 0
    Uhhh...you would still need two control motors, to move the etchasketch knobs...and to actually USE the mouse, the ball has to be in.

    In a nutshell, what the hell are you talking about.

  46. Niftyness^2 by Argon+Sloth · · Score: 1

    It's only a mater of time until we get a case mod based on this kind of rig. Looking at my computer's glowing inards is getting old. But if I could rig an EAS to the Mobo and write a controller that would randomly draw new patterns. That would be cool.

    --
    Laziness is a virtue, anyone who bothers to tell you otherwise, is clearly lacking it.
  47. Re:Final Year Project?!? by Anonymous Coward · · Score: 0

    It's their final project for a class, not their degree. Learn to read.

  48. Nice idea... but what if...? by enginuitor · · Score: 0

    I remember I used to have an electric Etch-A-Sketch that had a little joystick, a battery, and two cheap DC motor drives inside. But of course, it didn't come anywhere near the "cool factor" of a digitally-controlled EAS.
    But why limit it to mouse-based control? Instead of reading mouse pulses, hook it to a 'n*x box, change the programming a bit, and make it an X/Y plotter... Have it graph your CPU load, network traffic, etc. /That/ would be a hell of a conversation piece!

  49. A friend of mine also built one by qromodyn · · Score: 1

    A friend of mine also built one in college (Carl R.) for his EE project. That was around 1991-1992. I don't remember the interface, but it might have been a joystick.

  50. Overall, not particularly... by Ellis+D.+Tripp · · Score: 1

    But the ones who entered science fairs tended to be, I guess.

    FWIW, I went to a Vo-Tech HS, and studied electronics technology. Myself and another student made a project out of a child's toy robotic arm (IIRC it was called an "armitron") that we rigged up with a half-dozen DC motors and controlled via the parallel port on a ZX81. Programmed in BASIC to execute simple moves. This would have been during the junior year of HS.

    --
    Remember "News for Nerds, Stuff that Matters"? Help make it a reality again! http://soylentnews.org
  51. Required for accreditation by Anonymous Coward · · Score: 0

    I don't find it impressive at all, because it's a requirement of ABET (the Accreditation Board for Engineering and Technology). If your school has an engineering program, and it's accredited, you have an ethics component.

    Basically every university engineering and applied science college in the US is accredited by ABET, so every last one of them have the ethics component. How gung-ho about it they are differs, but every program has to address it to ABET's standards.

  52. Re:Department of Redundancy Department by anubi · · Score: 2, Interesting
    Before we flame the guy too bad, I think its pretty obvious what he's talking about.

    Inside the mouse is a ball driving two optical encoders: one for X, one for Y, mechanically placed 90 degrees apart.

    The optical disks and detector are made in such a manner as to produce a quadrature encoded output.

    With very minimal "glue logic", these signals could be changed to the quadrature encoded drive signals required by a stepper motor.

    This would have eliminated the whole processor.

    But, they used a roundabout way of doing it.

    I'll often do things for my own edification that are not optimal just to see how things work.

    In this case, the students got to experience working with the AVR compiler, programming in machine code, and real-world interface design, so I won't bang on them for not doing it in such a way I would have if I were gonna make a million of 'em.

    Now, if I had found out that they were just drawing lines on the CRT screen, I would have posted a very vile commentary on the state of what is passing for education these days. What I saw looked appropriate to me for a class project for BSEE.

    Just for funsies, my final project in College back in the early 70's was building my own oscilloscope from scratch. I thought I was gonna get really good bandwidth because I was using 45MHz IF tubes from television receivers as my CRT drive. Got my design finished... Surprise! I got 10KHz! Well, so much for my rude awakening to plate resistance and capacitive loads... but the professor gave me full credit anyway because I offered the correct explanation of why I didn't get the response I expected.

    --
    "Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]

  53. Why does this remind me of LOGO by laejoh · · Score: 0

    Would be fun if those guys hooked it up to the logo language. So instead of moving the mouse they would do something like:

    REPEAT 4 [ FD 100 RT 90 ]

    and voila (IIRC), a square :)

  54. check this out by Anonymous Coward · · Score: 1, Informative

    There are far more impressive projects that students in this class have made:
    http://instruct1.cit.cornell.edu/courses/ee476/Fin alProjects/s2004/aeh28/Website/index.htm

    Check out the rest of the projects students in this class have made: http://instruct1.cit.cornell.edu/courses/ee476/Fin alProjects/

    Keep in mind that students in ece476 only have about a month to do their final project and that is on top of all their other classes' final projects.

  55. Done at U. of Delaware also by Prof.+Pi · · Score: 2, Informative
    One time in the late nineties it was a course project for a sophomore computer architecture course in the EE department at the University of Delaware. One of them was kept assembled and is still sometimes used for a Parents' Day demo. It had stepper motors and could draw really nice curves.

    Cornell has turned itself into a Microsoft shop, so it's appropriate that they're all excited about something that others did years before.

  56. Re:Department of Redundancy Department by Anonymous Coward · · Score: 0



    Before we flame the guy too bad, I think its pretty obvious what he's talking about. (...) With very minimal "glue logic", these signals could be changed to the quadrature encoded drive signals required by a stepper motor. This would have eliminated the whole processor."

    THANK YOU.

    You have restored my faith in EE.

    Kids these days... I swear. Half of them couldn't find their ass with a flashlight, two hands and a GPS. The point of engineering ISN'T "Yaaay!! we g0t 1t 2 werk!" ... Achievement is "We sat down, thought it through, and built our solution using the fewest number of parts, and the least potential for failure as possible."

    The bulk of this kid's project is unnecessary to achieve it's ultimate goal. Cute concept, poorly thought-out, margainal execution. I'd give this project, honestly, a C-. Mod me down however the hell you want.. Like it or not, this kid (unfortunately) is an example of someone who didn't quite think the problem through..The whole essence of what engineering is supposed to be about.

  57. Had one over 30 years ago. by blair1q · · Score: 1


    It was called an X-Y plotter.

  58. Re:Department of Redundancy Department by anubi · · Score: 1
    Thank you for the kind words.

    I guess there are several perspectives for viewing this project.

    When I saw it, I did not see it much as a production plan for making the device, as much as I saw it as a platform they had constructed to demonstrate their ability to serially communicate to a mouse, process the info with a microcontroller, then drive motors based on the result. An exercise in interfacing.

    I also consider that AVR processors are quite cheap, damn near cheap as a couple of glue logic chips. The programming is a one-time effort, and the use of as many off-the-shelf commodity items, such as the mouse, AVR processor, motor driver chips, etc, shove quite a bit of R&D costs away. As you know, the very chip in the mouse that reads the quadrature encoded X-Y wheels and prepares the serial info stream for the PC is also a microcontroller.

    Their implementation indeed used two microcontrollers, when in reality none at all were needed. But then, reliability of AVR processors is hardly questionable ( as I have yet to see one fail ).

    Their design can be viewed as redundant, but knowing what I do about the elemental parts of the design, for commercial use, I would probably come up with something very similar. I would want my customer to be able to walk into his local "Radio Shack" and buy spare parts should something break. If I made attempts to redesign a standard mouse, I could easily create a lot of chaos in the supply chain.

    From my chair, I would have given them an A. I would have also considered it good for a Master's project if they threw in the control systems math for matching the controller to the stepper motor... as the motor and load have inertia - and optimizing it for fastest error-free operation would require implementation of some DSP in the processor.

    However I certainly see your viewpoint - its the same as mine when I was working in aerospace - as simplicity, reliability, and power consumption were our prime design objectives. Until Goldin and his team of tie-guys managementized the industry, elegance of design was top dog.

    I didn't survive when the aerospace firm I worked for managementized - as I stood up for what I believed - and quickly got labeled as an uncooperative member of the team. What they were asking me to do involved asking me to give up my computer and circuit simulator which I understood intimately, and in its place they were demanding I use some proprietary piece of stuff I did not understand... and thinking I could still produce good design using it with even faster time frames, as well as asking me to take on several things at once. Damm, my own OS is still God's Original Wet-Ware version 1.0 (Homo Sapiens). There are only so many things I can consider at a time. Does one tell the tie-guy the honest truth and lose one's job, or be a nice subordinate little minion and hope for the best, hoping something where I do not have twenty years worth of experience backing up my judgment will work?

    I certainly understand about the guys who can't find their ass with both hands and a GPS... the problem is that they have gone beyond engineering and often become an engineer's boss.

    --
    "Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]

  59. Stylus Trick by Anonymous Coward · · Score: 0

    ...but can it move the stylus without drawing?

  60. I've done this too. by shaydr · · Score: 1

    I recently (may 2004) graduated from the University of Colorado with a BS in Electrical and Computer Engineering. One of my three big projects was a computer-controlled etch-a-sketch. The class was focused on real-time embedded projects using VxWorks. We used a video capture card and an x86 based VxWorks system to do line following on a captured drawing. (With the goal real time capture and drawing no time to tweak). When we started we thought we were original, oh well. It sure was a sight to see it trace out the drawing (last official act for my undergraduate degree). My professor took digital video of it working, and I hoped it was online but alas no. Why am I making the post? Just to throw in my experience and say this kind of activity is not easy but ultimately is fun.

  61. Geez, I should have patented it. by Russ+Nelson · · Score: 1

    I built one of these back 1978. Yes, virginia, they had etch-a-sketches back then. And stepping motors. Yes, and even personal computers. I remember when we added 4KB of RAM, for a total of 24K! You could do anything in 24K! Mu-hahahahahaha!
    -russ

    --
    Don't piss off The Angry Economist