Physicist and squirrel gastronomer [Carsten Dannat] is trying to correlate two critical social economical factors: how many summer days do we have left, and when will we run out of nuts. His research project, the Squirrel Café, invites squirrels to grab some free nuts and collects interesting bits of customer data in return.
This cat feeder project by [Ben Millam] is fascinating. It all started when he read about a possible explanation for why house cats seem to needlessly explore the same areas around the home. One possibility is that the cat is practicing its mobile hunting skills. The cat is sniffing around, hoping to startle its prey and catch something for dinner. Unfortunately, house cats don’t often get to fulfill this primal desire. [Ben] thought about this problem and came up with a very interesting solution. One that involves hacking an electronic cat feeder, and also hacking his cat’s brain.
First thing’s first. Click past the break to take a look at the demo video and watch [Ben’s] cat hunt for prey. Then watch in amazement as the cat carries its bounty back to the cat feeder to exchange it for some real food.
[Helios Labs] recently published version two of their 3D printed fish feeder. The system is designed to feed their fish twice a day. The design consists of nine separate STL files and can be mounted to a planter hanging above a fish tank in an aquaponics system. It probably wouldn’t take much to modify the design to work with a regular fish tank, though.
The system is very simple. The unit is primarily a box, or hopper, that holds the fish food. Towards the bottom is a 3D printed auger. The auger is super glued to the gear of a servo. The 9g servo is small and comes with internal limiters that only allow it to rotate about 180 degrees. The servo must be opened up and the limiters must be removed in order to enable a full 360 degree rotation. The servo is controlled by an Arduino, which can be mounted directly to the 3D printed case. The auger is designed in such a way as to prevent the fish food from accidentally entering the electronics compartment.
You might think that this project would use a real-time clock chip, or possibly interface with a computer to keep the time. Instead, the code simply feeds the fish one time as soon as it’s plugged in. Then it uses the “delay” function in order to wait a set period of time before feeding the fish a second time. In the example code this is set to 28,800,000 milliseconds, or eight hours. After feeding the fish a second time, the delay function is called again in order to wait until the original starting time.
While prepping for the upcoming apocalypse, the [prepforshtf] folks had time to design and build an automatic chicken feeder. It’s a very simple design (the best kind) that is made from standard PVC drain pipe. The pipe is positioned vertically and filled with chicken feed. A T-joint at the bottom of the pipe allows chickens to access the food inside. As food is eaten away, gravity pulls more food down to the feeding area.
That sounds pretty straight forward but it quickly became clear that checking the food level was a chore, almost as much as just feeding the chickens everyday. To remedy the requirement to constantly check the food level, the automatic feeder system was taken apart and modified to include a level indicator. Now, inside the 4-inch pipe resides a plate that resembles a butterfly valve.
This plate doesn’t control the flow of feed like a normal butterfly valve would, the feed actually holds the plate in a vertical position until the feed level drops below the plate. Since the plate has a heavier side, it will rotate when the feed no longer holds it in position. A large red pointer was attached to the plate’s axle and, since it is on the outside of the feeder, it allows a clear indication that the feeder needs a refill.
This is a great project that shows that even simple projects can be very beneficial in everyday life. With no electronics or batteries to fail, this feed indicator will certainly be very reliable. No doubt the chickens will be happy. Check this out for a more involved electricity-powered feeder.
[Brian] has a fairly large 400 liter aquarium and loves the fish that call it home. Unfortunately, sometimes life gets in the way of keeping those fish fed on a regular basis. There are automatic fish feeders out there on the market and [Brian] gave one a try. Although it worked, it dropped one huge clump of food in at a time (rather than sprinkling it in), the food hopper held a very small amount of food and the unit drained a new set of batteries in less than a week. Fifty euros were spent on purchasing that auto feeder and in the end it wasn’t any more convenient than just feeding the fish.
Faced with a tough decision on whether or not to buy another product he may not be happy with, [Brian] decided to make his own automatic fish feeder system out of parts anyone can find lying around the house. The main housing is a small Tupperware bin, inside of which 3 pieces of plastic were glued together to make a v-shaped hopper. The fish food is loaded into the hopper and as it falls to the bottom it meets a reverse-spinning drill bit that acts like an auger, pushing the food out of the container. The drill bit is powered by a small stepper motor connected to the drill bit by an improvised coupling made from a silicone sealant cap!
The control system is an Arduino and a stepper motor driver chip. Through trial and error [Brian] figured out that 100,000 half steps of the motor dumped a good amount of food into the tank. The drill bit delivery method even sprinkles the food nicely for total fish enjoyment. To keep the food flowing at regular intervals, an AC timer unit controls how often the Arduino is powered on and subsequently feeds the fish.
[Ben Miller] and his dad combined forces to create this automatic dog feeder. It not only keeps their two schnauzers happy, but gives them peace of mind as they can double-check that he feeding happened by pulling up an image on the Internet. Make sure you make it through all three posts of the build to get the entire picture.
The project started with some research which turned up a project that used a commercially available automatic feeder. That one used Arduino, but because of the cost the board plus a WiFi shield is a bit high, [Ben] went with a Raspberry Pi and a USB WiFi dongle instead. The Pi is much more powerful and adds the functionality for capturing images via a webcam.
After a convoluted process of connecting the Pi to the existing button traces on the automatic feeder it was time to start coding. The system runs from a Perl script which monitors a Gmail account for remote commands (in addition to a regular feeding schedule). The final touch is a bit of mechanical engineering which splits the output into two bowls so the dogs each have their own serving.
We still use the Autodine we built several years back but its single-serving limitation has always kept a second version on our project list. Hopefully seeing a well-executed system like this will motivate us to get building!
Sometime the hacking topics come in waves. For instance, we were tipped off about this pair of automatic fish feeders just an hour apart from each other. Maybe it’s that time of year when people are about to go on Holiday and want to make sure their marine pets don’t go hungry?
The feeder on the left is a true hack. It’s built from a pair of servos and a pill bottle. An ATtiny85 drives the motors. One is mounted to the other, allowing the cap which catches and distributes the food to move along two axes. When it rotates into place under the pill bottle it bumps against a stick to open a flapper releasing more food.
On the right is a feeder that precisely doses the food. That’s because it includes a separate chamber for each feed. A worm gear drives the hopper, with screw heads pressing against a leaf switch for position feedback. This one is well designed and built to last.