This instructable was created in fulfillment of the project requirement of the Makecourse at the University of South Florida (www.makecourse.com)
This make was my intro into using the arduino microcontroller and writing code. I admit that there is a lot more that could have been done to make this project more awesome!, I applied the K.I.S.S. approach to my first build. This build is open ended with a lot of room for awesomeness, and indeed, more awesome awaits as I intend to add a temperature sensor and timer based control.
However, as a novelty, this device serves as a fun and geeky method for dispensing any dry material with a particle size diameter below 1.5 mm or so.
Step 1: Gather Materials
- Arduino UNO Learning Kit (includes LCD, Stepper motor + driver, breadboard, jumper wires, infrared sensor and remote, and USB Cable) $49.99
- DC-47P DC Series Heavy Duty Electronics Enclosure
- Use the attached CAD File to and export the model of the dispenser as a .stl file. 3D print the parts for the fish food dispenser
- Phillips head screwdriver
- box cutter
- JB Weld Epoxy Putty or plumbers putty
- Sand Paper
Ideally, you will also have a small hungry fish in need of feeding ^_^
Step 2: Finish 3D Printed Parts
Printing quality can vary. Take the time to make sure all pieces fit and that movement between pieces is unhindered.
I spent a long time sanding the rotating wheel so that it can rotate freely within the bottom housing. The attached video set at 18x normal speed is just a glimpse at the amount of sanding required. This can be remedied by adjusting the tolerances for the 3D parts prior to exporting the .STL file for 3D printing.
Step 3: Build the Circuit and Wire Components
Use the attached wiring diagram to wire the arduino to the pertinent components. The program used to generate the wiring diagram is the commonly used Fritzing program (available here for free)
This build utilizes several arduino components including:
- Infrared receiver and remote
- Stepper motor and stepper motor driver board
- 16x2 LCD Disply with I2C bus
- the I2C Bus allows for easy connectivity and control of the LCD display. You will need to include the appropriate libraries in order for the arduino sketch in the following step to work
- The power supply to the Arduino can be any 5V power supply (USB or battery)
Step 4: Upload Arduino Sketch
***You must have the Arduino Sketch IDE Software installed on your computer (available here)***
The main sketch to be uploaded to the arduino is titled FishFeeder_CODE
The "functions" file should be included as a tab as it contains the definitions for the "forward" and "backward" functions that are used in the main sketch. These functions drive the stepper motor operation. I wrote my own operation regime that would allow for two of the internal elecromagnets of the stepper to receive voltage during the step cycle so as to apply twice the electro magnetic force, thus acheiving a bit more torque. This will be necessary as this make is intended to deal with small rigid particles that could possibly induce frequent jamming. I felt that increasing the torque would be beneficial for this intended use.
Step 5: Outfit Enclosure
This step invites much customization. First, I arranged the components within the enclosure to my liking. As seen in the photos, the breadboard and the Arduino UNO fit snuggly within the enclosure.
The stepper motor driver was screwed to the exposed screw hole within the enclosure.
Epoxy putty was used as both a sealant and an adhesive. A small saw, box cutter, and drill were used to cut holes into the enclosure to make the holes for the dispenser resevoir, dispenser outlet, and for the IR receiver. The epoxy putty cam in handy to "clean up the holes and make the components appear more flush with the enclosure, limiting unwanted movement. An additional piece of tubing was attached to the outlet of the dispenser to better direct material exiting the dispenser.
Step 6: Plug and Play!
Now just connect the arduino to a power source and place the enclosure on top of the animal's enclosure. Make sure the dispenser outlet hole has a clear path to the water below.
I hope you enjoyed this make!