Here’s a cool little variation of that handy little function called Wake on LAN — [Jonathan] found himself locked out of his apartment one too many times, so he decided to add his own fail safe backup in order to get inside without a key — using a Raspberry Pi of course.
His apartment is one of those older style ones where the door is always locked and you use a buzzer to let someone in (or a key to get in yourself). This made it super easy to add some internet connectivity to the system. [Jonathan] tapped into the buzzer with a relay since the system uses medium voltage AC to operate. A Raspberry Pi triggers a transistor using its GPIO to click the relay on and off, effectively controlling the lock.
Using a WiFi dongle he’s connected the Pi to his home network and written a simple perl script to trigger the relay — all he has to do is visit a URL on his phone or computer and the door will unlock instantly!
Once the system worked [Jonathan] soldered all the components onto a breadboard and hooked it up. He still needs an enclosure for it, but it’s been working well since he installed it.
Another option would be to use an RFID tag system through the door, which could be pretty cool as well.
[Shawn] recently overhauled his access control by fitting the doors with some RFID readers. Though the building already had electronic switches in place, unlocking the doors required mashing an aging keypad or pestering someone in an adjacent office to press a button to unlock them for you. [Shawn] tapped into that system by running some wires up into the attic and connecting them to one of two control boxes, each with an ATMega328 inside. Everything functions as you would expect: presenting the right RFID card to the wall-mounted reader sends a signal to the microcontroller, which clicks an accompanying relay that drives the locks.
You may recall [Shawn’s] RFID phone tag hack from last month; the addition of the readers is the second act of the project. If you’re looking to recreate this build, you shouldn’t have any trouble sourcing the same Parallax readers or building out your own Arduino on a stick, either. Check out a quick walkthrough video after the jump.
Continue reading “Quick and Dirty RFID Door Locks Clean up Nice”
[HSP] got tired of locking his door with a key, so he decided to upgrade to a keypad system which he’s designed himself.
It uses an Arduino Mega with the standard 44780 display, a standard keypad, and the “key override” (shown above) for fun. The locking mechanism is a standard 12V actuator based lock which was modified to run off of only 7.5V, by softening up the spring inside and running it upside down (as to let gravity help do the work). The whole system draws less than half a watt on standby, and engaging the lock peaks at only 4-7W.
What’s really clever about this design is how he locks it from inside the room. He’s programmed the Arduino to write 1 to address 128 of the EEPROM — at power on it will increment this by 1, and after 5 seconds, it will reset to 1. This means it can detect a quick power cycle, so you can lock the door by turning it off, turning it on for a few seconds, and turning it off and on again — he did this so he didn’t have to make a button or console, or any kind of wireless control on the inside. Continue reading “Door Lock Provides Peace of Mind With Real-Time Security”
When it comes to home automation, there are a lot of different products out there that all do different things. Many of them are made by different companies, and they don’t often play very well together. This frustration ultimately led [Daniel] to develop his own Python based middleware solution to get these various components to work as a single cohesive system. What exactly did [Daniel] want to control?
First up was the door lock. [Daniel] lives in an apartment building, so there are actually two locks. First, a visitor must be allowed into the building by pressing a button on the intercom system in the apartment. Second, the apartment door has its own dead bolt lock that needs to be opened and closed. [Daniel] was able to control the building’s front door using just a transistor hooked up to an Arduino to simulate the press of the physical button. The original button remains in tact so [Daniel] can still easily “buzz” in a visitor.
The apartment’s dead bolt was a bit trickier. There are off-the-shelf solutions to control a dead bolt, but they are often expensive. [Daniel] built his own solution using a simple servo motor bolted to the door. The servo is controlled by the Arduino which is in turn controlled via two broken intercom buttons that already existed within the apartment. The buttons were originally used to either speak to or listen to a visitor before buzzing them into the building. They had never worked for [Daniel] so he re-purposed them for his own project. The whole DIY door locker is enclosed in a custom-made laser cut wooden box.
Click past the break for the rest of [Daniel’s] story.
Continue reading “HAL is Duct Tape for Home Automation”
When the folks over at PinMeTo moved into a new office, they were dismayed to find out an extra key would run them a whopping 500 sek (~$75 USD). Instead, they decided to build their own automatic door lock using the Electric Imp system.
If you’re not familiar, the Electric Imp is a small SD card designed to provide internet (Wi-Fi) functionality to consumer devices. While it looks like an SD card, you cannot just plug it into any SD card slot and expect it to work — it still needs a prototyping board. We’ve seen it used to make a wireless thermal printer, or even make a tweeting cat door to let you know of any feline intruders!
Anyway — back to the hack. To move the lock cylinder they’re using a basic RC servo connected directly to the Imp. A flex sensor is installed on the side of the door over-top the lock — this provides feedback to the Imp whether or not the door is in fact locked. The Imp then communicates to Everymote to allow for keypad access from your mobile phone.
It probably ended up costing more in time and money than a new key, but hey, it looks like it was a fun project to do!
College students have returned in droves to dorms and apartments at campuses everywhere. So this is the time of year we usually start seeing some coded entry hacks. [Charmonkey] recently took on the challenge at his new apartment. There were some caveats though. He needed to ensure the Landlord could still enter using a key, and he didn’t want to alter the door or the jamb in any way. What he came up with is a coded entry system that can turn the deadbolt.
In order to mount some hardware on the door he removed the inner part of the dead bolt assembly and used the pair of threaded tubes on the adjoining lock section as anchor points. This holds the Pokemon tin he’s using as a project box securely in place. The rest of the components all mount to it. These include the stepper motor that actuates the deadbolt, a switch for manual operation, an Arduino, and a motor driver board.
He got really creative with the keypad. The wires connecting it travel through the door’s peephole and into the smaller plastic project box that hosts the rest of the hardware.
[Jeremy Blum] wrote in to share his LibeTech QR Code Door Lock project. He developed it during his Senior year at Cornell University along with three of his classmates. It seeks to move away from magnetic card locks in favor of optical locks that authenticate based on a QR code.
The hardware he’s using here is definitely cost prohibitive, but we’re sure the concept could be greatly simplified. In this case a BeagleBone running embedded Linux monitors a feed from a webcam. When it detects a QR code it compares it with a database of approved keys and will unlock the door for you.
There are problems with this technique, one being that an attacker might be able to get a usable photograph of your key without you knowing. But the majority of hotel locks in use right now are even less secure than that. On the upside, the key to your room can be emailed to you for use on just about any device with a screen, or printed out on a piece of paper.
You can find [Jeremy’s] presentation video embedded after the break.
Continue reading “QR code opens doors to you”