The PIR Sensor - Motion Activated Art

[sonicfuker]

What in the fuck. You're shot.

[titoo3071]

youtube.com/watch?v=k0g64fo5HP­0

[titoo3071]

dear beautiful lady, good work, if i were supposed to do it i would have done to play the musical notes such as in a music. what i meant is the notes played here are not music it is like a noise what i prefer you to do is to select the musical notes and play it. so that the playing shall be like a music and not like a noise. because i know to play keyboard the sound here are like not music. if you need any help from me? you can.

[TheBern0ulli]

Hi,

You said that the 1kohm and the .1uF reject frequencies greater than 10Hz? I think I'm missing something but: Fc=1/(2*pi*RC) the 3dB attenuation for the component values given isn't ~1.59KHz? I might be missing something here.

Thanks,

[freezzertime]

Thank you, thank you, thank you!

[MrTryg]

Thanks a lot for posting this video. It's really great. Taught me bundles in just under 7 minutes. I'm happy too to see the MSP430. I have one and have only just nibbled at it yet. It's very cool. Thanks again!

[catman72]

loved the laser trick :-)

i use 4 laser pointers (hotglued parallel) to check optics.

its a trick i saw in a museum, they explained optics to kids.

well, i'm a kid too. fits me perfectly.

[plazmafeld]

That was hot, tell me more, an make yr dance a little longer, an can i build a spaceship in yr back yard?

[imanonymous93]

As if an attractive girl is teaching me electronics:L

[jayantismyname]

1:30 on the PIR circuit what does .luf stand for. please help thank you.

[jeriellsworth]

@jayantismyname .1 micofarad It's a measurement of capacitance.

[jayantismyname]

@jeriellsworth Oh! I Thought it was L.... TY.x



[linagee]

Did you consider using an Arduino?

[jeriellsworth]

@linagee Sure. I have a few of them kicking around the shop. Programming isn't the area I like to work normally, so I don't go out of my way to add MCU's to hobby projects.

[rampike74]

You are a genius.

[nullt0ne]

What type of Oscilloscope are you using?

[jeriellsworth]

@nullt0ne That is lower end Tek 100mhz 4 channel.

[MisterAlexUk]

I'm definitely trying this. It's always great to see the way you design your circuits and why you make certain choices; I understand the theory behind the circuits that you're building but no one ever really explains why they create circuits in a particular way; unlike you. I've just received Rapid Prototyping of Digital Systems too... It has been really helpful in configuring my own touch screen driver via FPGA.

Thanks for all of your videos Jeri, you're really helping me to learn a lot.

[lumaix]

wow that's a lot of effort for a simple detector and midi sounds. I would've setup a cheap computer + webcam with facial recognition using the OpenFrameworks API... then you could do really advanced stuff (like recognising different people or the height of people).

[jeriellsworth]

@lumaix That's easy? Guess it's all perspective.

[lumaix]

@jeriellsworth Mad respect to electronic-geeks! Looks like voodoo to me; software-hacker. Interested to hear your thoughts about Arduino- everybody I know is going mental over them because it makes electronics accessible to all.

[MattJpwnz]

@lumaix Jeri did state at the beginning that the solution had to be inexpensive and small.

[AmazGraz]

Sweet! That could be used on the cookie jar, or the front grill on the car. And as far as getting it; I do. At least, after I have viewed it another 75 times I'm sure I'll be on top of it.:D I think.

[AmazGraz]

@AmazGraz And I'm not being facetious, but the toilet would also be an interesting place to use it. No, not like the conventional method. A recording that sounds like the sounds you are producing in this video would make a trip to the restroom an interesting experience if it were set up to wait until one was through. But the artist was on the right track. And I'm sure he asked the right person. That was pretty cool. And as far as art is concerned, I'll bet there is a lot of room for creativity.

[AmazGraz]

@AmazGraz Well, I was just thinking like an artist. My mind isn't usually in the toilet. :^D But it was a fascinating journey. And I had never bothered to understand how the photo sensor actually worked. After all, I thought it was a photo sensor, I think. And the way you explained it was pretty cool. Makes me want to build one. That's why I thought of those things. :^D

[CampKohler]

My neatest sound from art was at the CA state fair; it was called "Heart and Lungs." The former was emulated by an old water heater tank periodically struck by a cushioned cam-operated striker. I entered the gallery and walked entirely around it to stand before the piece as you exit.. Then I realized it bonged continuously, but I had heard nothing until I actually saw the thing! Going back to the entrance, I now heard it, but somehow it had been "invisible" to my hearing earlier. Weird.

[Ivultorky]

Oh god your dance moves are HAWT!

[dashxdr]

Coincidence about the msp430. I used the ATMega32u4 from adafruit to program the flash on the msp430 using the 2-wire jtag.

Cheap $20 solution for a jtag programmer.

[kiekeboe2u]

Very cool. At first I was afraid it was gonna end up like one of those annoying toys that starts moving when you walk by them in the aisle of super W

[MsCuriousturtle]

Question: wouldn't an ultrasonic detector work as well...and you could vary pitches associated with range of motion? How does the PIR work differently from the ultrasonic?

[jeriellsworth]

@MsCuriousturtle Other sensors will work also, but PIR sensors are dirt cheap will adjust to surroundings automatically. It will take more software to do this with other sensors.

[H3nryHomesweet]

Wow, immense work!

[WillBourne999]

Solely the musical part of this design could be sold as an instrument in it's own right... An alternative to the theremin? haha :-)

[Cokecanninja]

Go, find your cat, pet his head, and say he's a good kitty. Then give him some tuna.

[Kmezon2]

such a detailed explanation, awesome

[frankbuss]

Nice project, but why not producing the audio signal, too? The quality and performance of the low-cost DIP chips provided with the LaunchPad might be not good enough, if you use something like PWM for the sound output, but there is the nice MSP430F1612 on the LaunchPad itself, with two 12 bit DACs, for a nice stereo output.

BTW: Farnell is a good shop, and delivers next day here in Germany, but the search engine sucks, compared to Digikey. How much did you get for your advertisment? :-)

[jeriellsworth]

@frankbuss You could generate the music with the MCU if you like. You're right there are some really nice devices in the MSP430 family.

[Films4You]

5:04 love to watch you dance

[markiduval]

DJ Jeri! *dances*

[onlywhenprovoked]

Great video. I picked up a couple of those MSP430 boards awhile back but haven't put them to use yet. Hell of a lot cheaper than an Arduino but I really do wish they'd have made those I/O's compatible for the sake of using interchangeable "shields".

[jeriellsworth]

@onlywhenprovoked I don't mind they don't fit the shields. The odd spacing with Arduino headers annoy me.

[shodanxx]

that's cool, I'm intrigued in making new musical instruments

a MAP sensor is an obvious candidate to make some new type of awesome electroflute, I bet there are tons of sensors that could be used in this way

it doesn't sound very musical though, even I would say dissonant and cacophonic

kinda like those door chimes made out of brass tubes that make ransom notes

I would suggest 2 things

"Bobby McFerrin Demonstrates the Power of the Pentatonic Scale"

"ToneMatrix - aM laboratory"

500 chars.

[shodanxx]

@shodanxx

maybe it would sound more consonance and harmonious and less like jazz

if the notes were limited in the same way they are in "tonematrix"

no matter what notes you use in that application it "always sounds good" +/-

I think that's the secret sauce, there was a great discussion of this on reddit but I can't find it right now

I'd really like for some art major to comment on this

[frankbuss]

@shodanxx "tonematrix" is cool! They've used a pentatonic scale, which sounds always harmonic, but sometimes a bit boring, because it is difficult to create tension and dissolving within such a scale.

One example of a pentatonic scale is only black keys on a piano. I've even tried to do an improvisation in one of my videos with this pentatonic scale, but looks like I'm a much better programmer than piano player :-)

[jeriellsworth]

@shodanxx Someone more skilled at music, could set up software triggers that sound better.  I'm far from a musician and the request was for random notes.

[DeJach]

How long in total did this project take you? It seems like it'd be a great project for a CE course to cover since it combines a lot of useful knowledge into a unified whole. (Op-amps ftw!)

[jeriellsworth]

@DeJach I think the total time would be 4-5 hours if you have a base to start with. I had a few snags, because I wasn't sure how the MSP430 digital oscillators worked. This would be great fun for a school project, since it gives a little analog, digital and MCU.

[edabean007]

also, when do we get to see the video of you dancing for the PIR sensor? :P

[edabean007]

@edabean007 wait .. just seen the last few seconds ... awesomeness :D

[edabean007]

just ordered my TI LaunchPad MSP430 last week .. Never coded anything before. I am hopeful that i will be able to make a light blink! Wish me luck!

[jeriellsworth]

@edabean007 I think the default loaded application blinks the LED, so you might need to shoot for two LED's. *wink*

[ericfontainejazz]

Person => Heat => IR photons => IR sensor => Analogue Voltage signal => Digital Microcontroller => Computer Program => Midi Commands => Keyboard Synthesiser => Music!

[gfxlonghorn]

So the first stage op-amp is simply acting as a high pass filter and not for amplification of the signal at all?

[jeriellsworth]

@gfxlonghorn It adds quite a bit of gain. If you pause the video at the plots or scope you can see the voltage scales are different between the PIR output and the first stage.

[electrodacus]

I will need to experiment with PIR sensors. Thanks for the great video.

[rohanr2]

What software are you using there to create the circuit?

[jeriellsworth]

@rohanr2 I simulated with LTSpice. It's a free tool from Linear Technologies.

[rohanr2]

@jeriellsworth ta - just downloaded it. What an incredibly fun piece of software :-D My future circuits thank you

[Turrican0815]

I love you ! sooooo long ^^

[Luudite]

woah....I need a lot more practice before I understand the greek used in this video.

[gnomencandle]

genius!

[batterymaker]

I could see the slogan now: "PIR is watching you pinch a loaf..." LOL!

[Tezcax]

Omg, that's awesome, I need to learn more about electronics asap

[technologicleenelson]

What circuit software is that at ~1:40?

[Gameboygenius]

@technologicleenelson LTspice

[marios2liquid]

Hi Jeri,

I was wondering what software were you using in this video? At 1:35 !! Is it Multisim? Thank you!!

[sonicase]

so the optoisolator is in your circuit or in the midi keyboard?

im also not sure how you gave the midi command as serial

will it work for inputs like just a regular potentiometer

and why did you use a pir insted of an ir range sensor

it would be cool to create just a simple midi keyboard with it

[jeriellsworth]

@sonicase The pir sensor will auto adjust to the background and is a bit more interactive, since the velocity of someone in the room effects the music too. IR, microwave, beam break are other options too. You could put any voltage source on the input like a potentiometer. Sky is the limit with midi. The code was 40 or so lines and most of it was from TI. :)

[sonicase]

@jeriellsworth cool thanks, i'll have to check the midi examples, i haven't really played around with my launchpad enough :/

[jeriellsworth]

@sonicase TI doesn't supply a MIDI example directly, but it's only setting the DCO timing correctly and sending 3 byte commands.

[jeriellsworth]

@sonicase oh yeah. The optoisolator is in the keyboard. If you want to receive or be a bidirectional there will be an isolator on your side too.

[Summoner7]

I have no idea how im subbed to you?... I have no clue :o

[jeriellsworth]

@Summoner7 I'm sneaky. I clicked the button on your computer when you weren't looking.

[Summoner7]

@jeriellsworth for the past days your vids pop up and im like I have no idea who this is but lets watch it i guess. I think your a SPY AND YOUR IN MY HOUSE RIGHT NOW! Or you can mindcontrol people

[morto360]

@Summoner7 I wish she was in my house >.<

[jeriellsworth]

@Summoner7 The video is from inside the house.

[obc993]

@Summoner7 same here

[speedman89]

This is the awesomest video I've ever seen.

[jeriellsworth]

@speedman89 Thanks!

[sciguy14]

watched this on element14 a few days ago, but really cool!