Your Personal Doorman


I often want to know who is at home when I’m on campus. If I’ve had a rough day – maybe I’d like to come home to chat with my roommate or maybe I’d like some alone time.

One might argue that Find My Friends has many of the features I require but as an Android user this feature is not available to me.  Another issue to point out is that if you live in an apartment building, like me, then there is some likelihood they they are not in the room – rather in somewhere else in the building.

If I was to extend the project, I would try to use IFTTT to notify me when someone enters and exits. Additionally, I would add temporary keys so that if friends or family are visiting they can temporarily unlock my door when they need to.

Proof Of Concept

To input the password, I decided to use a keypad. Every person has an associated key, so we can track who is entering the apartment. To further incorporate the kinetic requirement of this project – I added an ultrasonic ranger which ‘unlocks the door’ when a person stands near the door from the inside.  There are also modes which can disable certain keys from working if you need privacy.

Crit2 Arduino

Link to videos



I'm a sophomore studying electrical engineering.

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