Automatic Pet Feeder

Hello, I'm new on the forum! And quite new on electronics as well . I want to build an automatic pet feeder for when I'm away. My idea was to have a container filled with the food, with a PVC or similar "L" shaped tube on the bottom. In the final part of this tube I'd like to place an automatic lid, that opens on a set schedule for a certain amount of time and then closes (I don't want to weight or any other exact measure of the amount of food, I'm not against it, but felt that it would be simpler to just test and program the opened interval according to an estimate of the amount of food I want to give, if I am mistaken then let me know!). I would also like to have it run with batteries, with an autonomy that, if possible, reaches 15 days.

So, I believe I need an automatic lid, a clock, and a controller. Any advice on where to start? Hardware recommendations?

Thank you in advance!

You want to have the feeder run unattended for 15 days?
Who are you feeding?
Type of food material?
Volume of each serving?
Frequency of each serving?
Fail-safe in case of a malfunction?
If you were going to be gone for 15 days, that last item in critical!!!

KMoffett said:

You want to have the feeder run unattended for 15 days?
Who are you feeding?
Type of food material?
Volume of each serving?
Frequency of each serving?
Fail-safe in case of a malfunction?
If you were going to be gone for 15 days, that last item in critical!!!

Click to expand...

It would be ideal, yes.
A small dog (in size, not age)
The food is regular, dry dog food
Volume of each serving around 2 cups.
Frequency of each serving: once a day
Fail-safe in case of malfunction? Great point. I was thinking about maybe something like the lid being "normally open", paired with an automatic disconnection if there is no opening of the lid for 2 days. Again, as I'm really new, do not know alternatives, what is the usual practice, etc.

Thanks for the reply!

Duke7 said:

what is the usual practice, etc.

Click to expand...

a web cam to check on the dog and a neighbor with a key that can check if you cannot.

I think a ready made time switch**broken link removed** would be a good way to start. You can not set the on time to less than one minute so if you require less than 1 minute you would need to trigger a timer for example an NE555 to give a shorter output time if required. These timers have an internal backup battery which seems to keep it working for several weeks. I think the difficult part is the dispensing part.

Les.