dodgey99 on instructables shows us his award winning 'Automatic Arduino Powered Pet Feeder'.
"This is my automatic pet feeder. Powered by arduino, using a 3D printed auger, and programmable with two feeding times with a user set quantity of food, with a battery backed up internal clock. My cats drive me nuts in the morning begging for food so I decided it was time to robotize feeding time
I got frustrated with pet feeders available in the UK. They are either the type that rotate and unveil a meal, up to four times only, or the only half decent machine with a hopper is horrific to program, forgets everything if you remove the batteries, and frequently fails to even deliver any food! I program here and there, and the last machine I used made me so mad just trying to set the feeding times I nearly threw it out the window.
America has some good machines but they start at $300 USD, and shipping would be painful to the UK, so I decided to make one!". - dodgey99
1 x normal RC servo - regular size
1 x continuous RC servo - off the shelf or hacked.
1 x 3D printed Auger parts (see auger step)
1 x 1 1/2" PVC T-Piece pipe
1 x Arduino (I used an Uno but any type will do)
OR ... for PCB (1 x ATMega328p, crystal, 2 caps, 5v voltage reg) - google "arduino breadboard"
1 x KY-040 Rotary encoder on board
1 x 16x2 LCD HD44780 compatible
1 x small push button switch (non-latching)
1 x food hopper - I used one for storing food with a firmly sealable lid - to stop feline criminal activity.
1 x mounting box - I built one from MDF
1 x 12v power supply - around 500Ma+ to be safe - driving the servos. You may need more.
For the full instructable visit; http://www.instructables.com/id/Automatic-Arduino-Powered-Pet-Feeder/?ALLSTEPS