Starting documenting the project today while the newest iteration is printing. I have used it for 3 years, and is now getting comfortable with it working. I will test the feeder with the new parts, and then upload images and .stl files.
The feeder part consist of some 75mm drain pipe. Inside the drain pipe I have a motor turning a threaded rod. On the rod it is mounted a platform witch is lifted by the turning rod. On the platform there is cat food for a weeks usage (I have 2 fat cats...). When the platform is lifted some cat food will spill over and out the drain pipe branch, down to the cat food bowl.
The feeding is triggered by the cat entering a trip plate consisting of a plexiglas plate with some 3D printed holders for some micro switches. the plate bends under the weight of the cat, and the switches are activated against the surface under the plate. This one is adjusted to my setup, and will need some adjustment for you to use.
Electronics is a ESP8266 getting signal from the trip plate, timing the motor action and total feeding at a day. This one is higly integrated with my smart home - taking a image from surveillance camera and sending it via telegram. Probably you want it differently, it is the easy to replace with an Arduino.