For someone who has never used stepper motors, real-time clocks, or built anything from scratch, [Dodgey99] has done a great job of bending them to his will while building his Etch-A-Sketch clock.
He used two 5V stepper motors with ULN2003 drivers. These motors are mounted on the back and rotate the knobs via pulleys. They are kind of slow; it takes about 2 1/2 minutes to draw the time, but the point of the hack is to watch the Etch-A-Sketch. [Dodgey99] is working to replace these steppers with Nema 17 motors which are much faster. [Dodgey99] used an EasyDriver for Arduino to drive them. He’s got an Arduino chip kit in this clock to save on the BOM, but you could use a regular Arduino. He left out the 5V regulator because the EasyDriver has one.
[Dodgey99] has published three sketches for the clock: one to set up the RTC so that the correct time is displayed once the Etch-A-Sketch is finished, some code to test the hardware and sample the look of the digits, and the main code to replace the test code.
The icing on this timekeeping cake is the acrylic base and mounting he’s fashioned. During his mounting trials, he learned a valuable lesson about drilling holes into an Etch-A-Sketch. You can’t shake an Etch-A-Sketch programmatically, so he rotates it with a Nema 17. Check it out after the jump.
If you’re paying attention, you’ll realize we just saw the exact opposite of this project a few hours ago: a CNC tool (laser cutter) controlled by turning Etch-A-Sketch knobs.
Isn’t there a turbo button on this thing ?
Needs a nicer font with curved lines.
Shaking it to erase would have been far more fun! I’m sure you could fashion a scaled up pager-style vibrating motor.
Some better gearing should speed this up a bit along with some new motors.
He didn’t make the etch a sketch did he?
Guess he didn’t make it all from scratch then. But I’m just a stickler
To make an Etch-A-Sketch to fetch the time from scratch, one must first invent the universe.
Classic.
Relevant:
https://www.youtube.com/watch?v=7s664NsLeFM
Would be faster to draw the number outlines left-right fashion as the bottom line is always drawn last due to home position.
I’d like to see a software challenge based on this hardware. Who can code the most efficient G-code producing algorithm for it using the fewest characters of code?
I love it. The idea is simple but he’s done a very nice finish to it. I just wish it was a bit faster.
Heh, by the time it reaches the last digit, it isn’t current anymore.
I enjoyed this. Obviously there’s a lot of room for improvement, but it is a very nice proof of concept.
I LOVE THIS AND MUST BUILD ONE NOW!!!! AND I ALSO LOVE BACON!!!!
I’m bacon!
I’m Bacon and I can tell time…. IT”S TIME FOR BACON!!!
I’ve built something like this in the past with a friend. Worked really well. Maybe we were just using the cheapest Chinese Etch-a-Sketches, but we found that the internal belts ended up breaking. Could be that they were given to students and they zeroed out the system by driving into the stops…
Now someone needs to make an Etch-a-Sketch controlled Etch-a-Sketch. :P
All your bacon are belong to us.
What do you get when you cross an Etch A Sketch, a Speak and Spell, and a slab of bacon? My next project…notice no Arduino, so it’s a hack.