Keyless door entry
Independent Design Project
During my first semester at UC Berkeley, I was required to carry a key whenever I left my dorm room. Forgetting my key or having to open the door when my roommates got locked out was irritating. I decided to design a mechanism to unlock the door when a pass code was entered correctly from the outside.
I was limited to the materials and tools I had in my room and some inexpensive parts I ordered online. I mounted a digital keypad to the outside of the door which interfaced with an Arduino micro controller. I used a servo for the actuation mechanism because of it's compact design and high torque. Servos typically only spin 180 degrees so I modified one so it could spin continuously and work as a winch. To accomplish this I took apart the servo, removed the physical regulators, and re-calibrated the potentiometer so the servo would spin freely.
I was limited to the materials and tools I had in my room and some inexpensive parts I ordered online. I mounted a digital keypad to the outside of the door which interfaced with an Arduino micro controller. I used a servo for the actuation mechanism because of it's compact design and high torque. Servos typically only spin 180 degrees so I modified one so it could spin continuously and work as a winch. To accomplish this I took apart the servo, removed the physical regulators, and re-calibrated the potentiometer so the servo would spin freely.
Technical Skills learned
- Arduino Code
- Analog Circuits
- Servo Communication
- Resourceful Rapid Protyping (string and rubber bands)