Adding a keypad to a key card lock


[Colin Merkel] had a little problem: he was continually forgetting his electronic key card, locking himself out of his own dorm room. Like any normal Hack a Day reader, rather than getting in the habit of always carrying his card, the natural impulse of course is to build this elaborate rig of electronics and duct tape. Right?

The result is an additional keypad that can be used to gain access…not by altering the existing electronic lock, but with a secondary mechanism that operates the inside door handle. An 8-bit PIC microcontroller scans the outside keypad (connected by a thin ribbon cable), and when a correct access code is entered, engages a 12 volt DC motor to turn the handle. It’s a great little writeup that includes a parts list, source code, and explains the process of keypad scanning.

It’s similar to the RFID-based dorm hack we previously posted. By physically operating the handle, most any approach could be used: facial recognition, other biometrics, DDR pad, or whatever inspired lunacy you can dream up.

Automated dorm room door

[Chris] wrote in to tell us about this project he did while living in the dorms. He built a system to automate his dorm room door. It handles unlocking and opening/closing the door via iPhone, secret knock, and even the key.  The lock/knob portion is handled by a servo while the opening/closing action is hydraulic. After living with it for a year, he says that it never gets old, but there were a few bugs. Apparently it would randomly open in the middle of the night sometimes. If you’re interested in doing something like this, but not damaging the door, maybe you should check out the RFID dorm door lock project.

Nintendo keyless entry

The Nintendo keyless entry system will vigilantly guard your door from intruders. Enter the right code and you get access, enter the wrong code and it will deny you and take your picture. [action_owl] did a fantastic job on this lock, using mainly recycled parts like an old CDRom and an Arduino. It works both with or without the computer. If you choose not to use the computer, you don’t get pictures of the people who entered the code wrong.

We like this project, but we feel it needs to be pointed out that this lock is pretty useless. Everyone already knows the code to get in is UP, UP, DOWN, DOWN, LEFT, RIGHT, LEFT, RIGHT, B, A.

How-To: Make an RGB combination door lock (Part 1)

Part 2 can be found here

Putting a custom designed electronic lock on your space seems like a geek right of passage. For our latest workspace, we decided to skip the boring numbered keypad and build a custom RGB backlit keypad powered by an Arduino. Instead of typing in numbers, your password is a unique set of colors. In today’s How-To, we’ll show you how to build your own and give you the code to make it all work.

Continue reading “How-To: Make an RGB combination door lock (Part 1)”