Electronic Pet Door

[Sono]

Hi
I'm trying to get a few ideas together to make a pet door lock.
I'm thinking something very simple that may be triggered by a small but powerful magnet attached to the pets collar, as we have a lot of strays using the door at present.
Any thoughts would be much appreciated.
Thanks

 

[Mike_2545]

Check out these commercially available ones
Electronic, Magnetic, Infra-Red and RFID Cat and Dog Doors

 

[EN0]

This may be a bit extreme, but it's awesome!

**broken link removed**