DIY 3D Controller

Make a 3D interface using an six resistors, aluminum foil, and an Arduino. Take that, Wii.

The basic goal here was to make a 3D hand-position sensing system that most people can build, while still preserving some semblance of functionality. To get an idea of possible applications, check out the demo video. If you think you can build one that is simpler and equally accurate, or slightly more complex and more accurate, share in the comments!


DIY 3D Interface: Tic Tac Toe from Kyle McDonald on Vimeo.

Step 1 Materials

Tools

• Arduino
• Processing
• Wire cutters
• Soldering iron
• Box cutter

Materials

• (3) 270k resistors
• (3) 10k resistors
• Solder
• Wire
• Aluminum foil
• Cardboard

Optional:

• Tape (e.g.: scotch)
• Shielded wire (e.g.: coaxial cable, ~3')
• (3) alligator clips
• 3-pin header
• Zip-tie
• Shrink wrap tubing or hot glue

Comments

[jonRomero]

i just finished building the circuit and made sure nothing short circuited, but nothing is changing even when i press the Space button. The arduino code is fine and the Processing code too is good to go. However The only warning message i get is


WARNING: RXTX Version mismatch
Jar version = RXTX-2.2pre1
native lib Version = RXTX-2.2pre2
[0] "COM3"

Does anyone know how to fix the RXTX Version mismatch ???

[pierceRom]

To anyone who actually got this to work ,

Does changing the aluminum foil to actual Aluminum plates work ?? I know they both conduct electricity but crinkled foil break easily unfortunately =/

[pierceRom]

Hi there !!! im totally new at this whole electronics thing and I wanna try this project but i ran into a bit of problem.

I have built the board and everything but my problem is with the code. Where exactly is the code for the arduino ?? Or is the program " Processing" code suppose to upload the code into the arduino ?? Sorry if this question seems noob but im really new at this =(

Thank you soo much for any help !!

[kylemcdonald]

there is a link to the arduino code at the bottom of step 6. good luck!

[pierceRom]

Thank you sooo much for the quicky reply !! So the interface code goes into the Arduino and the TicTacToe code goes into Processing ??

But shouldnt there be a camera in the code somewhere so i can interact with the TicTacToe game in 3d ??? Where would that code be ??

Sorry once again if my questions seems completely retarded , im really new at all this unfortunately =

[kylemcdonald]

hey, you're welcome -- the delay in my response to a question is usually exponentially proportional to the complexity of the response, so the easy ones get answered fast :)

there is no camera involved here -- you just need to look at your hand :)

if you want to get a camera involved, you'll have to hack the processing sketch.

for the video i posted, i recorded the camera separately and composited them afterwards, just for demoing how things worked.

[pierceRom]

Last question i promise !!

It seem that there were two files " Interface" and "Tic Tac Toe " in the download section .

So the interface code goes into the Arduino board and the TicTacToe code goes into Processing ??

Sorry but could you clarify that a little bit ??? Many many thanks for your help !!

Cheers

Pierce

[Nannerman]

I wonna play tick tack toe on a 3x3x3 led matrix made up of 2 colored leds :D. I just got an arduino uno so lets see if I can make something half as cool as this.


Now looking at the materials, I think I need to build this.

[shaemmerling]

could this be used as a 3d mouse for spinning 3d models with hand motion. like grabbing an pbject and spinning it. i know its been a while since this has been commented on but thought id try.

[aefields]

How does one convert the input from the sensors to a scale from 0-255 for PWM output?

[mrmerino]

left hand green.

[avillanueva1]

I had problems with the code, the processing tell me that i have an error ArrayIndexOutOfBoundsException 2, am i doing something wrong?

[jimmy dean]

I am also getting the same error. It is pointing to this line in setup:

serial = new Serial(this, Serial.list()[serialPort], 115200);

Has anyone solved this yet?

[jimmy dean]

Ok, I figured it out.

If you were getting that error from the serial line, you have to make sure that the serial variable at the top is the correct serial port. If you look above the error, it should show the serial port that you are using. Mine was com4 so it showed:
[0] "COM4"
Therefore in my situation I had to change the serial variable to 0.

I also got that error randomly sometimes when I would run the program. I think that came from the board sending data before the program starts receiving it and then the program starting halfway through a line. To fix this I just made sure to hit the reset button at the same time I hit run on the processing code and it solved my problem.

Hope that helped :)

[willrandship]

Hey, remember me? :P

I'm doing it ruch better now. last time I made many mistakes, like the foil touching, the circuitry on the wrong side of the cable...

[DemonSpawn]

Im going to try combine this and a 3x3x3 bicolor led cube to make a interactive 3d tic tac toe! im so excited!

[im3733]

If you do that, consider having the cube be clear so that you can see the center cell. otherwise, you will only be able to see 11 of the 12 cells.

[willrandship]

I think he meant where the leds just hang in midair, by their wires, which will be clear.

[pp21]

i have read all the comments and tried EVERYTHING! i can not get anything to show up, on the computer screen or in the box thing! what am i doing wrong. please hep me.

[pp21]

what kind of resistor
1/8-Watt 10K Ohm Carbon Film Resistors
10K Ohm 1/4-Watt Carbon Film Resistor
or
10K ohm 1/2W 5% Carbon Film Resistor

[kylemcdonald]

there is no significant power usage here, so it doesn't matter -- any of these are ok.

[SubFusion]

would it be possible to have a double sheet and connect resistors to the mcu
in every corner of a sheet and then get 2D resolution X , Y of the capitance of the sheet. etc like comparators are used to deside the direction of light by have four photoresistors and making a wall between everyone of them in a cross.

I think I'll try

[sebasto-oo]

Dear Kyle, Bravo for that great idea, it opens a wide new world of  cheap DIY potentialities leading to high end original control interfaces.

The problem is that, even though i scrupulously followed your building instructions, i can't seem to have the device interact in any way with my hand.

I just finished building it, and i seem to have a problem. The code seems to be working fine, the TTT demo at least : the code compiles just fine on processing, i just had to change the value of the serial port. Processing lists and finds the serial ports, compiles OK, the Java windows opens on the TTT, but no matter how hard i wave my hand around, there seems to be no interaction at all.

I must confess that i suffer a double handicap : i'm french, and i don't know much either about electronics or about Processing ;-)

But i'm very eager to learn, believe me.

I have a intuition, though : i could not find a single hint about where to connect the shielding wire onto the plate's side (the alligator clip's side). I tried different combinations, like soldering the core wire and the shield wire together, leaving the shield wire unconnected, etc. But none of them work until now.

Since i obviously forgot something, somewhere, would you have a hint for me ?

Thanks a lot for your help, and again, Bravo !

Seb

[kylemcdonald]

Thanks!

When I built this I didn't understand the idea of shielding for capacitive sensing very well. So the shield is actually completely unconnected from anything. It does act slightly "shieldy", but it's more of an antenna. (For a real "shield", you need to use an opamp to sense the voltage on the wire and surround it with that same voltage.)

If the code isn't doing anything, there is one instruction I may have forgotten to include: you have to hold down the space bar while moving your hand from the furthest outside corner (most distant from all the plates) to the furthest inside. This acts as a calibration step (as shown in the video) to normalize the input.

Since writing this instructable two years ago, I've learned a bunch more about capacitive sensing and know better designs that also use very few components. I'm finishing my graduate degree right now, but when I'm done I'll come back and post a new instructable. For now, if you're interested in expanding your electronics knowledge a bit, check this out: thereminvision.com/version-2/TV-II-index.html

[dagenius]

Is there any way to have this act as an alternative mouse?

[kylemcdonald]

Sure, once you have a 3D screen :)

If you reduce it to two dimensions, yes. But using IR distance sensors are probably a better solution to that problem.

[dagenius]

But could you use the z dimension as a click function? that way you have a complete mouse...

[kylemcdonald]

Yeah, that'd would work too :) There are a few more comments here from Unit042 and willrandship that explore that idea, you might want to check them out!

[nrdesign]

Would this actually work through some kind of plastic or plexiglass? I mean, just to protect the aluminium foil.

[kylemcdonald]

Plexiglass has a dielectric constant of 2.6. Compared to air (1) and water (34) this isn't so bad. Plexiglass should be fine. The thinner the better, and wood (1.4) would be slightly better than plexiglass.

[willrandship]

Plus with wood you get a much more aesthetic feel than crinkled foil. The plexiglass wouldn't hide it. Would varnish have a high or low constant?

[kylemcdonald]

According to this list: http://www.clippercontrols.com/info/dielectric_constants.html Silicone Varnish is about the same as wood (2.8). It probably wouldn't make a huge difference regardless as it'd be a thin layer.

[willrandship]

Yay! I was hoping it would be, as wood looks much more professional when varnished. I was thinking about selling some if I can get a process down. Arduino mini + USB FTDI + This = ultra 3d pointing device! You could even have separate settings for up down for movement or left-right for movement!

Naturally, I would want your permission before selling any.

[kylemcdonald]

The license on this instructable is just CC-Attribution, so you don't need my permission to sell any variation. You just need to clearly reference the instructable as the source of the idea. Feel free to modify and sell it :)

[willrandship]

Good! I'll be sure to do that. I wouldn't want to steal credit. For selling, though, I would probably use a boarduino as they are only $15 and small enough to be built into something. They also have the necessary I/O pins. All in all, I could probably build one for $30 overall. An added feature could be that if you take it apart, you have an arduino! :P

[willrandship]

Hasn't this instructinle been going for a couple years? I'm suprised people are still leaving comments on it. It is a featured article though. :-P

BTW I actually built one of these a while age, but never got around to finishing it due to the fact that tv-style coax cable has a tendency to let solder just slide off...:-( I'll probably finish it soon, though, seeing as I finally found a way to realize my mouse Idea! I might post an instructible about it sometime...I wanted to do it for the arduino contest, but I was a little late. Luckily, the contest rules will let me enter next year, so there's no reason to delay!

[kylemcdonald]

Even if this is old (a little over a year), it's always nice to see people interested in these things. When I made it, I was hoping to explain something kind of mysterious in an accessible way -- and stay up-to-date with the comments to provide feedback and ideas. I'd like to think it's for all those reasons people are still coming back :)

I hope your implementation goes really well! I'm planning on posting a new version of this within a few months that is much more accurate and requires only a few more components.

[willrandship]

Oh goodie! I hope it has a suggestion on how to attach the cables better. I had problems with coated coax cable. It doesn't help that I'm a clumsy solderer, either....

So, more components means better, right? I am expecting something mind-boggling!

The main reason I want this as a mouse is for black & white. God game + motion hand = real experience. Now I need johnny chung lee's 3d implemented!

[kylemcdonald]

I think the best way to go, if you want really robust cables, is to use shielded RCA. You can get RCA jacks on the cheap, and RCA cables are abundant. They're basically the less-heavy-duty version of coax.

More components means higher accuracy. I was working with 14" distances and 1/4" accuracy at 30 Hz with a 5x5" sensor.

[willrandship]

I hadn't though of rca...does it allow for easier soldering? or, better yet, I could take apart an old vcr, desolder the jacks, and make a connector for the arduino!