[Bozar88] lives in an apartment building that has a buzzer at the front security door. Guests find your name on the panel next to that door, and press a button to ring the phone just inside the entry of each apartment unit. He decided to extend the built-in capabilities by adding a morse-code entry password which unlocks the security entrance automatically (translated).
He designed a circuit and etched his own board which fits nicely inside of the wall-mounted phone. It uses an ATtiny2313 to implement the coding functions. The device attaches to the intercom line in order to detect incoming button presses from the entry panel. There’s some protection here to keep the signal at or below 5V. The output is two-fold. The microcontroller can drive the microphone line using a transistor, which gives the user audio feedback when the code is entered. To unlock the door an opt-isolated triac (all in one package) makes the connection to actuate the electronic strike on the entry door.
The video after the break is not in English, but it’s still quite easy to understand what is being demonstrated.
Continue reading “Apartment entry morse-code lock”
One thing you can look forward to when arriving at home after a long, arduous day at the office is some peppy theme music when you walk in the door. [Sebastian Sommer] built the system, and shows it off in the video after the break by dancing to James Brown’s I feel good.
The setup uses an Arduino as a microcontroller. It monitors a hall effect sensor on the jamb which detects a passing magnet on the door. We guess this means the system doesn’t know if you’re coming or going but perhaps a future upgrade would add an infrared beam to detect your legs as head out the door. The music itself is played by an SparkFun MP3 shield which has a decoder chip, microSD slot, and audio jack for the powered speakers. [Sebastian] grabbed a copy of [Bill Porter’s] mp3 shield library to get the project up and running quickly.
This is a pretty cool addition if you’re already using an Arduino for a door lock or vice versa. Or maybe you’re not home enough to make this hack worth it, in which case you simply must take this music playing Tesla coil hat along on your commute.
Continue reading “Your theme song greets you at the front door”
[Flowolf] added an auto-locking RFID entry system to his front door. He used our favorite fabrication system, acrylic and threaded rod (we also like to throw in aluminum angle bracket from time to time). The support structure mounts underneath the escutcheon plate for the lockset, keeping the main acrylic sheet flat against the door.
An RFID reader and Arduino run the system, with a button inside to unlock the door. But if power were to fail, you will still be able to get in or out manually. When you are using the electronic system, a stepper motor connected to the geared lock knob by a chain is what grants access, then revokes it again five seconds later. The wire going up out of the this image is for a switch that lets the unit sense when the door is closed.
As shown in the video after the break, you can turn the auto-lock feature off. But we’d like to see an emergency entry feature, like a knock-based lock, because eventually you will leave without your keys!
Continue reading “Geared system adds RFID to regular door locks”
In 1966, [Gene Roddenberry] introduced fully manual doors powered by a stagehand on Star Trek. The fwoosh sound of the door was later dubbed into each show, but progress marches on, and now [Alex] created his own Star Trek-style automatic doors for his house.
The build includes a ‘control panel’, and [Alex]’s door operates in three modes: Open, and stay open; Close, and stay closed; and Automatic. The control panel itself is fairly remarkable. A small puck interacts with a magnetometer underneath [Alex]’s counter. If the puck is pointed towards ‘Open’, the door stays open. If the door is pointed towards ‘Closed’, the door stays closed. If the puck isn’t near the magnetometer, the door operates in automatic mode with the help of a few IR sensors to detect someone trying to get in or out of [Alex]’s kitchen.
For the mechanical portion of the build, [Alex] used a One meter long piston with the quietest air compressor he could find. We can’t tell from the video after the break if the compressor ever kicks in, but [Alex] says it’s about the same volume as his fridge. As a small added bonus, the new automatic door does have a fwoosh sound, just like [Gene] would have wanted.
Continue reading “Star Trek style pneumatic doors that don’t require a stagehand”
It seems that [pppd] is always rushing out of his apartment to catch the bus, and he finds himself frequently questioning whether or not he remembered to lock the door. He often doubles back to check, and while he has never actually forgotten to lock the door, he would rather not deal with the worry.
Since he finally had some free time on his hands, he decided to put together a simple device that would help end his worry once and for all. Using an ATtiny13, [pppd] designed a circuit that would detect when his door has been unlocked and opened, beeping every few seconds until the lock is reengaged. The circuit relies on a reed switch installed inside the door frame, which is tripped by the magnet he glued to his door’s deadbolt.
He says that the system works well so far, though he does have a few improvements in mind already.
[Larry] and [Carol] just upgraded the coop to make their lives easier, and to help keep the chickens happy. The image above is a chicken’s-eye-view of the newly installed automatic door. It’s a guillotine design that uses the weight of the aluminum plate door to make sure predators can’t get in at night. This is much easier to fabricate than a locking coop door would have been. Some leftover aluminum channel guides the door on either side, with a spool above it to wind up some rope, thereby lifting the door.
You can see the belt-drive motor is also mounted inside, out of the element. To the right of the image you can just make out a plastic food container. This protects the electronics from the elements. Inside you’ll find an H-bridge to drive the motor, a real-time-clock to make sure the schedule is well-timed, and an Arduino. There are a couple of reed switches which let the microcontroller sense the position of the door.
After the break you can see a demonstration video, as well as a slide show with build details. The motor is pretty quiet and, although it spooks the chicken in the demo just a bit, we’d be they’ll be used to it in no time.
Continue reading “Motorized coop door lets the chickens out for you”