Project Cat Feeder

[techy101]

In another attempt to make my wife shake her head and sigh I've been working on a WiFi enabled cat feeder based on the Electric Imp. It's mostly built from reference designs but should do what I need. The device will be powered by a 5V USB adapter and a lithium battery backup. The basic premise has been using a cereal dispenser and replacing the hand-knob at the front with a servo. Activating the device will make the servo run for a pre-determined amount of time and then a camera module will snap a picture and upload it to a server as verification that food was in fact dispensed. My WiFi router and modem are on a pretty large battery backup so they should keep operating for quite a while if the power goes out, so this is designed to follow suit with its internal battery backup.

It uses a BQ24073 to manage the battery and a pair of LM3668SD buck/boost chips (different fixed output values) to generate 3.3V for the Imp and 5V for the servo. I've added a 4MB SPI flash memory IC to act as storage for the image while it is being uploaded to the server. Others had slowly streamed images from the camera up to the server, but I like the idea of having a concrete place to hold it prior to upload (Plus it's a way to learn to work with multiple SPI devices and external memory, both of which are new territory for me). The camera also operates over SPI. I've also got a pair of FET's that shut off power to the servo when it is not operating to try and save battery life if it loses power.

This is my second revision of the board design and part of the goal is to get it as small as is reasonable to fit inside the plastic feeder case. The main assembly will take place in my DIY reflow oven, and final touchups and difficult components will be done by hand. I have access to a stereoscope at my internship and do a lot of rework on boards of this size/density, so it shouldn't be too bad to finish by hand. Total board size is 40mm x 42mm.

I would love feedback on ways this could be improved as I'm still fairly new at this.

While it's still quite a work in progress, here is the design as it stands today:

[Bud]

You should take this project to Kickstarter, it is going to be a big hit.  Better yet if you could make the cereal dispencer levitating.

[ignator]

What is the purpose of this feeder?
Is it to control the feeding of an obese feline, or to feed when your gone on a long trip?
If it's the latter, then what is the availability of this, so you don't come home to a starving cat. Also, who's cleaning the litter boxes. And what prevents the water from being contaminated from a cat that pukes into it. You know they don't give a damn where they puke.

I have a feeder (purchased product from skymall) that is built with 6 pie like sectors, this rotates under a cover that only allow access to one of these sections. It's uses a main spring, and a battery timer to let it index with a 2-24 hour delay. It failed once with kibbles preventing the indexing. Lucky we only go for max of 2 days. Fat cat passed away.

[hamdi.tn]

Nice project    really useful if you go for a trip , can be a nice project in kickstarter , you may need to think of what can be done if the mechanical part fail

[Falcon69]

a feeder is a great idea, but, i'd be more impressed if you made a self cleaning litter box that actually worked!

[SeanB]

a feeder is a great idea, but, i'd be more impressed if you made a self cleaning litter box that actually worked!

It's called a cat flap that leads out...........

[Falcon69]

I keep my cat indoors.  Keeps them safe from other animals and cars and those pesky fleas, which carry diseases that get the cat sick.  She's a good cat.  Feeding her is easy, but cleaning litter box sucks!

I bought one of those automatic cleaning cat boxes before.  It didn't work very well. Was suppose to scoop the stuff out and into a little pouch that you remove and discard.  It never worked right, and the noise it made, i think it scared the cat and she wouldn't use the litter box.

An automatic feeder is a great idea, especially if you take a trip for a couple weeks, but, that leaves the problem of the litter box still. At what point, would the cat STOP using the litter box if/when it builds up too much?

[Falcon69]

hmm, that's not a bad idea. 

Have a bucket that holds 40lbs cat litter that comes down a tube and into some sort of a spreader.  Then, make it so the cat box itself has 3 parts. A base box, a sifter, and a discard with closing lid.

Make it so when the cat is done doing his/her business, the sifter lifts up, depositing the good cat litter to the bottom, bad stuff up top, then tip the sifter and all the stuff falls into the discard box and an automatic lid closes.  Then, the sifter vibrates and settles back to the bottom of the box.  Then when that is done, it activates a predetermined set amount of litter to come down the tube, and a comb like thing moves back and forth in the box to spread it.

Hmm, complicated, but, if the motors are all quiet, I don't think it would bother the cats much. This would save litter as well.  Could even incorporate some kind of a light perfume cat friendly spray as well to finish it all off.

You could even incorporate a low level litter warning for the bucket holding the fresh litter, as well as a warning for the discard box for full level.

Hell, I'd buy something like this. No more bad smell from litter box, and easy discard tray.  All i would have to do is just pour a fresh box of litter into the bucket once a week/month, and throw out the discard box every couple of days.

Hell, I'd help design this thing.  We'd just have to find some way of manufacturing it all.

I love my cat, but I hate changing that pesky litter box. 

[rdl]

You can train a cat to use the toilet. I did it once. I never could get her to flush it though.

[Falcon69]

I think I would train my cat to get me a beer out of the refrigerator, before I would spend the time to train her to use the toilet.