Conclusion

While building the mechanics and tuning the electronics took me longer than expected, the result was really nice: all the hardware neatly fit on the inside of the door, without using screws or nails or anything else that would damage the door. I used gaffer tape to make sure the device stays in place, but that's more a security measure than a neccesity.

The device works quite well, too: I've made a quick movie to show it off. The only problem is that opening the door assumes that you can keep a rythm in your knocks, and unfortunately, the people in the flat where it's installed don't all seem to be musical enough...

Last 10 comments Show all

paradox wrote at 28 Aug 2010, 6.35:

Nice hack, one way to counter the rhythm of the flat mates is to do the same thing fingerprint security does, and have a close enough is good enough method. I like how you just chuck things together and tinker to make it work

raheel wrote at 8 Aug 2009, 0.49:

wow. thats really cool.. but is it necessary to do this in assembly?. can we do this in C programming?

Amir wrote at 27 Apr 2009, 11.29:

great and Beautiful

MOHD TAHA wrote at 15 Aug 2008, 17.50:

HI ,THANK AND YES TO MORE

Shaggy wrote at 15 May 2008, 19.30:

I like it. The door looks fairly lightweight - probably some hollow honeycomb. It should be possible to use a magnet and reed switch arrangement, too.

fluxcap wrote at 26 Apr 2008, 6.31:

you should eliminate the knock sensor and use an automotive keyless entry !

rick wrote at 4 Mar 2008, 17.03:

hey i have a question. where can i buy those ATtiny? and can you explain me exactly how to put that firmware on the ATtiny2313? answer me at: rickvanoosterhout@home.nl thnx

tes wrote at 15 Jan 2008, 14.50:

brilliant!!!!!

wictro wrote at 13 Jan 2008, 20.30:

Neat-o! i would store all the dirty money, drugs, guns and hookers there ^_^

spazbob wrote at 6 Jan 2008, 1.19:

I agree with troy.

Sprites mods: Knock to open - Conclusion

Conclusion