The Feeder Tweeter - It’s autonomous, it’s solar-powered, it feeds, it photographs, it tweets images when a bird comes to feed, and it’s open source.
A PIR (passive infra-red) sensor detects when a bird lands at the table to feed, and triggers the camera. Photographs are then uploaded to Twitter. PIR’s a great choice here because it only responds to warm-body heat; if a leaf blows in front of the assembly, nothing will trigger, but if a toasty-warm little bird stops by for some seed, the sensor will detect it, and set off the camera.
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