[leevonk] sent us this quick and dirty home automation set up. Using photo resistors and your computer screen, you can drive as many relays or actuators as you want. [leevonk] is simply using changes in brightness on his computer screen to set off relays. This makes it easy for someone who has no programming knowledge and a tight budget to set up some automation. You could even do remote automation by connecting to your pc via VNC. Be careful taping things to your screen, wouldn’t want to damage it.
I don’t think people with a “tight budget” have enough screen space left.
Bonus: free opto-isolation ;).
I am sure that most people have a spare 15″ monitor, even a CRT. Most video cards are dual-output. There is all the screen space you need.
Ummm… better not be driving anything important… a blue screen or loss of power ( or MS update or IM message or …. ) and your house becomes possessed.
Is 1-wire automation really that hard or expensive?
Wow throwback to the CoCo and Vic20 home automation.
I did this when I was 12(in the 80’s) to ring a bell when certian events happened by the cursor moving under the phototransistor.
This is less a hack and more a
electronics and computers 50: introduction to computer hacking – how to use your monitor to trigger stuff.
If it’s the creator’s first foray into electronics, sure, but I hope he’s not going to leave it running like that for long — the windows screenbuffer doesn’t seem like a stable interface with windows popping up all over and whatnot.
If his PC has a parallel port, that’s a much better way at interfacing electronics.
I’m using the parallel port to let people control the Xmas lights in my room. All I need to do that is a transistor and a relay. With the parallel port you can control 8 devices.
You can control my light a http://drivemeinsane.com/?cam=22
this has to be one of the most redneck automation hacks I’ve seen.
just spend $5 on a parallel card and do it properly.
come on, this is seriously entertaining, and undoubtedly a hack. this just shows hacks are like snowflakes. (damn winter)
tight budget? a lcd is a few hundred u.s. bucks. an avr microcontroller, connectable to usb, can be had for about one. last time i checked photoresistors were quite expensive too, compared to standard optoisolators, which can also work off the parallel port as someone else noted. reuse an old crt? that eats up a lot of power. energy isn’t free you know.
Some of the things you post are awe inspiring… this? i dunno man. this is a fail in my mind. gotta keep the computer on all day and a dog feeder bowl is like $10. Undo the taped sensors when you’re at home remember to reattach before work? this automation is too much work. FAIL
the post description on hackaday sort of misses the point of this project by mentioning remote control via VNC. the remote control is done over the internet via the webcam feature of yahoo messenger, maybe I didn’t make that clear enough in the project description, so I’ll update that.
Also, people mentioning cost of an extra computer. At least in my neighborhood (brooklyn ny) I find old computers on the sidewalk quite often, these are often either working or in need of a hard drive.
For people mentioning other ways of doing this via parallel ports etc, yeah I know, I’ve done it that way in the past plenty of times with parallel ports, serial ports, RF communication, national instruments cards, PIC microcontrollers, basic stamps, etc. The point of this project is to make remote controlled home automation accessible to people without programming or server administration knowledge.
I’m not typing this in a confrontational manner, just trying to clarify some things, hope you at least find the project amusing if not useful :)
I love the indirection! This idea needs to be taken to the next level. I know the idea of this is no code but what if your home system was monitoring a few public webcams that are accessible by you. For example a security camera in your office, one in your apartments lobby, etc. The software on the home machine could be set to look for light motions. Such as a circle drawn with a flashlight to turn on some lights.
I guess the only side effect would be the people arround you that think you are nuts. :)
this is pretty neat but a bit unwieldy. I would recommend an FTDI232 USB based system (PIC programmers use this and the drivers even work in Vista) – you can obtain these from Spark Fun among others.
Alternative is to use a surplus broken USB keyboard and use the lights to control up to eight inputs with a 74HC138… :)
-A
I remember reading about this technique many years ago in one of those “Engineer’s Mini Notebooks” (written by Forrest Mims III) they used to sell at Radioshack. His version used QBASIC (ahh, memories).
It’s creative, but pretty unreliable if you consider the impact that screensavers, ambient room light and crashes can have – especially considering how cheap home automation stuff is these days.
this is so jack’d from Forrest Mims III book introduction to sensors from radio shack originally published in the early 80s …