Creating homemade motion sensor to camera

[goonthortech]

im a student working trying to start a project creating a motion sensor and camera outside my door way, was wondering if anyone had any ideas of how i should get started. i don't want to buy the sensor because i want to learn how to produce the product from scratch, any help would be great

 

[berkeman]

im a student working trying to start a project creating a motion sensor and camera outside my door way, was wondering if anyone had any ideas of how i should get started. i don't want to buy the sensor because i want to learn how to produce the product from scratch, any help would be great

Welcome to the PF.

The keywords here are "passive infrared" (PIR) sensor: http://en.wikipedia.org/wiki/PIR_sensor

 

[Lsos]

I needed to get a heads-up of neighbors coming to complain whenever I have a social gathering. I ended up simply using a smartphone as a wireless webcam for my computer (there is an app for that), and I downloaded some motion-sensing program for the computer. It compares each frame to the next and detects any changes, and it works pretty well. I even rigged it up to automatically shut down or reduce the music whenever it sensed someone coming. At the very least, it makes the neighbor think twice about his sanity, and it makes the subsequent negotiations easier.

Anyway, it was basically a software solution. The hardware is on-hand in pretty much any household.