Harry Potter Spell

Your comments have really got me thinking here.

What components would WE want? That one is VERY clear to me!

But first, let me explain my plan for my project. My immediate goal is the following: I want my daughter to be able to wave her wand by Christmas time, and have it turn on and off the lights on the tree. Also, I want to have a second type of movement that makes the star on top spin!

The current architecture I have planned would be the following:

  1. An infrared LED on the tip of the wand to emit a steady IR light. I was hoping to use an IR array from a night vision camera I borrowed, reflected off the tip, but in testing, it doesn’t seem to be enough light. For the LED, I’m thinking a watch batter with an LED in a simple small casing, and a small button, will have to do.
  2. A wiimote connected to a PC that reads the signal, as per the project you suggested, @JackANDJude - thanks for the excellent tip!
  3. Some simple software in C# and/or Python to interpret the wand movements (more on this below). When a relevant movement is detected, the software will call out to the API for the cloudBit component.
  4. A circuit connected via the cloudBit, preferably to the Arduino component. I have one, but I haven’t studied how it works yet. The next step, then, is based on some naive assumptions about the Arduino.
  5. Based on the input to the cloudBit (the only “parameter” seems to be voltage % - would it be possible to use that value to determine the next step?), an output signal is sent to the appropriate circuit (e.g. turn on/off the lights for one movement, or turn on the star for the other)
  6. The lights circuit would be connected to a simple Christmas light string on the tree that takes regular DC batteries (3 AA, or 4.5V)
  7. The star circuit would use the motor to spin the star, either using the timeout bit, or just via software

Getting back to what kind of bits we would WANT, for me the main thing I want to be able to do is to be able to play with “normal” external circuits (in this case, the Xmas lights). I don’t see a standard way to do this. The easiest way would be to take a wire bit and cut off one end, then use those wires to connect to any external 9V DC circuit. What I’d really like to see is an adapter bit that would let you plug in a littleBits circuit as if it were a battery. Then I would be able to control electronics via littleBits circuits of my own invention. As it stands, I ended up doing my best to make my own littleBits interface using a piece of tossed out plastic, some squares cut off the lid of a tin can (to work with the magnets), some super glue, and some wires (I’ll post online when it’s done and working).

Even cooler would be a bit to interface with AC circuits! Although I imagine that would not only be bulky and expensive, but dangerous.

Working on the littleBit interface piece, it occurred to me that this would be the PERFECT opportunity for a 3D printer! Imagine being able to print a plastic square with the right shape to interface with littleBits, and hollow centers through with you could pass some thin wires to connect with the V / S / G lines.

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I forgot to add:
I’ve been studying neural networks. By Christmas, the wand movements will probably have to be as simple as waving them up and down for one spell, and left/right for the other. But when I have more time, I’ll hopefully be able to write some algorithms to actually see the difference between Wingardium Leviosa and Aguamenti (and all the other spells shown on the Harry Potter map!). My plan would be to then create a library that takes x,y coordinates over time, and output one of these spells whenever the correct movement is detected. From that, you would be able to plug in any interface (e.g. a smartphone accelerometer, as you previously suggested), and do anything you want with the output (unlock the home screen of the phone for Alohomora, or turn on the phone’s light for Incendio).

@timothy_high. You, my friend, are positively cookin’! Check out the video on this page about pairing the ir transmitter with the AC switch.

I look forward to following your progress, which I hope includes pics!

Oh man, the AC switch would be PERFECT! Too bad I live in Brazil - I don’t think I’ll be able to get one shipped here by Christmas. Also, it looks like it’s currently only available via the home automation kit, which is pricey indeed.

Also, I hadn’t seen it before, but you’re right: the hardware development kit is pretty much what I’m needing right now. I’ll have to improvise my own for now :stuck_out_tongue:

Hey @JackANDJude, it’s published! Check out http://littlebits.cc/projects/wizarding-wands

I actually have a version that works with Arduino to choose between 3 spells, but I haven’t been able to get my daughter to help me make the spinning star for “Locomotor” :smile:

The IR reflection off the wand is really bad. I found I got better results with a plain lightbulb, which makes me think this isn’t what they use. I bought a security camera with a much stronger IR LED array (up to 50 meters) just to make sure, but it hasn’t come in the mail yet!

Anyway, if you get a chance to play with this, let me know. And thanks again for the help!

That’s great, @timothy_high ! I’m happy this discussion was useful for you, and I hope you get a Christmas version of the project up today for the http://littlebits.cc/hackyourholiday contest (tweet your project page with #hackyourholiday) !!! When you do, be sure to show someone waving the wand. :smile:

Oh man! I have to get my daughter to help me, quick! We’ll need to whip something together for the Locomotor and Aguamenti spells, too!

Unfortunately, I have some commitments tonight… the deadline is midnight in what timezone??

EST - It’s 11:00 AM there now. You can do it!

Outstanding!!! I’m so happy you all pulled this off! @timothy_high @JackANDJude !!! That’s exactly how we all should help each other within our projects!!! Great work! Happy to see it on the projects page!! We have to take the Community to another level! Your dedication is truly inspiring!! :slight_smile: Can’t wait for the future of littleBits! You all are setting standards!! It’s an amazing feeling bringing ideas to life!!

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@timothy_high Just tweet the Wizarding Wands project with the #hackyourholidays tag to include it for the contest. For realz, you already have a star ornament and Christmas lights in there, so I say it counts.

So, at the last minute I finally solved the mystery of the bad IR reflector! Talking to an electrical engineer friend, he suggested that the problem could be one of frequency. Not all IR signals are alike.

Since the Wiimote is already effectively paired with its own emitter, I gave that a shot with the wand. It works! I don’t know if the effective range of frequencies is limited for the wand, or it’s just that the Wiimote itself is what’s limited, but I do know that when you go all-Wii, you get magic!

I’ll be updating all my videos and pictures with the new setup (and, hopefully, my daughter) this weekend.

I finally put up a better video of us using the wand: https://www.youtube.com/watch?v=16ApbujMj_k

I’ll make a much better how-to video later, but first I need to make some improvements to the software (I want to include all the different spells, and let you choose!).

Great new video! It really shows the wand in action. I love the water bottle, lol! What other spells are you thinking of incorporating?


This morning I already made some progress on the software. I hope (I have to test to see if it’s working enough to be practical) to incorporate ALL the spells from the park. From the interface, you can pick any 3, and have them correspond to the 3 outputs on the Arduino. Almost ready!

Then, what you do with them is up to you. I’m still thinking about what my next setup will be, but I might power more Christmas decorations as a start.

I have the “opposite” question. I’m going to universal in a week and I wanted to “cast spells” without a wand by waving my “hand.” After looking through your findings I’m trying to decide if I should try some sort of reflector or a coin cell battery and an IR LED tucked into my hand. The question is, 940 or 880 nm? Any suggestions? Thanks.

It looks like an AC switch, as well as a whole lot of other bits, is coming your way soon! Congratulations on winning the #HackYourHoliday contest! :smile:

Soooo excited - I can’t wait! Thanks again for your help! Now I’m thinking of porting this over to Android and iOS. Magic automation, here we come! (now, which bit would be best for the washing-up spell…? http://harrypotter.wikia.com/wiki/Washing_up_spell)

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Hi! Sorry, just saw this question now!

I would love to see what you find out. I don’t have an answer to that question because I only thought of it after our last day - no time to experiment. I have no idea what the right frequency is (I don’t even know what the frequency is on the Wii, although I could probably look it up now).

Here’s what I know:

  • The wand works by reflection
  • It works for the frequency that the Wii uses, and probably better than the frequency for security cameras, although I’m not sure about that
  • With the Wii, I was able to use a plain remote control, although those blink rather than providing steady light

I’d say the more you experiments you can do, the better! Ideas:

  • See if a remote control will work
  • Try a steadier IR source (probably single source point, although their sensors have 4)
  • Try a reflector
  • Just for kicks, see if people could use plain tinfoil!
  • Try taking some video of a sensor to see if the lights blink at all

Have a good time, and let us know what you find!

@timothy_high I am going to Universal one day next week, and I am planning to bring a pulse, oscillator and an ir led. @Patrick_littleBits how many Hz can the pulse or oscillator do? What if I double up with two oscillators before an ir led; how many Hz could I reach then?

Wow! I just got back from a trip to the Amazon! No IR sensors there :stuck_out_tongue:

I like your hi-tech approach. Let me know what you find out when you get back!