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Turn a light bulb on with every new user or download

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Re: Turn a light bulb on with every new user or download

#31

Post by izak30 »

ultimoo wrote: post #30

This is when I feel envy toward engineers who can program hardware. I'm so involved with Ruby and HTTP and CSS etc. that I have negligible knowledge about Arduino, Raspberry Pi, and Beaglebone. I don't even know where to start and whether it will be a fruitful exercise (i.e. will I be able to devote sufficient time to it to actually learn something worthwhile). Anyway, this is a neat project and I wish you good luck…

With any of these three platforms you could be doing this project in an afternoon. Processing isn't any harder than Ruby. You can do it.

Check out http://Raspberry.io for some resources the python community put together to use Raspberry Pi

Check out makezine for resources designed for people who aren't even familiar with programming. It doesn't take much to get up to speed with some basic on/off circuits. With a little high-school physics or just some asking around of friends you can get custom devices going.

Re: Turn a light bulb on with every new user or download

#32

Post by laumars »

ra wrote: post #11

BIG FAT WARNING: If you're going to relay your Raspberry Pi / Arduino to mains electricity, be very, very careful! Mains electricity can KILL. Make sure you learn about safe shielding, connecting and grounding practices. Above all, be extremely cautious! I can't stress this enough. EDIT: For more information: http://tubelab.com/Safety.htm

LEDs would be much better suited for this.

In fact if I had the free time then I'd build a binary display for page hits using a series of LEDs on a Raspberry Pi (sadly I have a million other projects going on at the moment - such as finishing my website so I can get hits to begin with hehehe)

Re: Turn a light bulb on with every new user or download

#34

Post by nkozyra »

mnutt wrote: post #4

This seems like a really great use for raspberry pi. I recently finished a project involving a pi + a relay to activate a door buzzer, written in javascript. It was surprisingly simple and straightforward. Besides turning on lights, the cool thing about relays is that most things involving physical push-buttons can be taken apart and easily wired up to a relay.

Arduino or Raspberry Pi are kind of overkill for this ...

USB breakout board -> MSP430 -> LEDs/Buzzers/Whatever

You're talking somewhere around $14.

Yes, you'll need to know C or assembly for the MSP430 and likely a scripting language for the PC, but it makes a lot more sense than bringing in all of that horsepower to essentially get an I/O and light an LED.

Re: Turn a light bulb on with every new user or download

#35

Post by nkozyra »

droopybuns wrote: post #10

Cool project! Maybe iterate it to use LEDs instead of incandescents. For hardware hacking- you have 3 types of hardware that can make life easy- but there are tradeoffs: 1) Arduino 2) Raspberry PI 3) Beaglebone Arduino is great when you want low power, but it isn't an awesome internet platform. Raspberry Pi is great when you're going to leverage a full blown PC Monitor, but using it for hardware hacking requires a bi…

Never forget the MSP430, which is either $5 or $10 depending on when you hit it.

Re: Turn a light bulb on with every new user or download

#36

Post by jacquesm »

This falls - as others have already commented - in the 'knows just enough to be dangerous' category.

Please use LEDs, don't even bother messing around with opto-isolators and so on unless you have experience with both mains electricity and designing safe circuitry.

Re: Turn a light bulb on with every new user or download

#37

Post by mikeash »

beagle3 wrote: post #25
ra wrote: post #11

BIG FAT WARNING: If you're going to relay your Raspberry Pi / Arduino to mains electricity, be very, very careful! Mains electricity can KILL. Make sure you learn about safe shielding, connecting and grounding practices. Above all, be extremely cautious! I can't stress this enough. EDIT: For more information: http://tubelab.com/Safety.htm

Others have mentioned the Belkin WeMo, which seems to be the best solution for anyone who doesn't want to mess with circuits (though I have no experience with, so can't comment). Does anyone know if it is available in a 220v format? But if you do mess around with RasPis or Arduinos for that, I can't stress how useful the PowerSwitchTail is http://www.powerswitchtail.com/Pages/default.aspx - you give it a low power si…

Thanks a lot for the link. I've been idly pondering a couple of projects that would involve switching mains power with a microcontroller, but didn't encounter anything like that at a price that made me want to consider it. You may have saved me from a fiery doom.

Re: Turn a light bulb on with every new user or download

#38

Post by StavrosK »

joshu wrote: post #13

Working with mains power is stupid. Don't do it if you can avoid it, especially if you don't know what you are doing. You can get a small remote power switch for $100 or so.

There are remote-controlled RF switches for $20 for four. The Raspberry Pi can send RF signalss to these switches. Unfortunately, I don't have an oscilloscope to reverse-engineer the signal for mine, so the most I could manage to do is turn them off (but not on).

That's a very safe way of doing these things. If anyone else knows how I can reverse-engineer the signal, I'd appreciate it (I also want to make the Raspberry Pi open my garage door, same deal).

Re: Turn a light bulb on with every new user or download

#39

Post by tehwebguy »

jacquesm wrote: post #36

This falls - as others have already commented - in the 'knows just enough to be dangerous' category. Please use LEDs, don't even bother messing around with opto-isolators and so on unless you have experience with both mains electricity and designing safe circuitry.

Agreed 100%. Not happy with the Pi's 3.3v pins and want to light something brighter than a couple of LEDs? Try this:

- 12v power supply (from like anything in your house)

- 12v LED strip (super cheap on eBay or basically anywhere)

- This awesome MOSFET from Adafruit http://www.adafruit.com/products/355

This is what I used for a cool RPi + RFID + LED project this year, write-up coming eventually, here's a clip for now: http://vine.co/v/bvZQVJLnemh - my example only has a few LEDs but in the final product I used strips with about 30.

Re: Turn a light bulb on with every new user or download

#40

Post by [deleted] »

StavrosK wrote: post #38
joshu wrote: post #13

Working with mains power is stupid. Don't do it if you can avoid it, especially if you don't know what you are doing. You can get a small remote power switch for $100 or so.

There are remote-controlled RF switches for $20 for four. The Raspberry Pi can send RF signalss to these switches. Unfortunately, I don't have an oscilloscope to reverse-engineer the signal for mine, so the most I could manage to do is turn them off (but not on). That's a very safe way of doing these things. If anyone else knows how I can reverse-engineer the signal, I'd appreciate it (I also want to make the Raspber…

[deleted]
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