Stap 1: Requirements

• 5v stepper motor with ULN2003
• Nodemcu esp8266
• Some jumper wires

Stap 2: Software

The food dispenser will be controller by a (small) microcontroller with Wi-Fi. There could be chosen for a different microcontroller for example a ESP32 or Arduino with Ethernet shield.

The IDE in which the firmware has been developed is PlatformIO. You can however, choose for a different IDE.

To allow the food dispenser to be connected to the internet through Wi-Fi you should edit the following lines in main.cpp

const char* ssid     = "SSID"; 
const char* password = "Password";

Once the firmware has been flashed, the microcontroller will listen at the configured IP address and port for a GET request called /feedCat. It will also expect a parameter named "move" followed by the value which represents how far the lid should open to drop food. In this case the request would be:

http://192.168.2.55/feedCat?move=70

If you want more food to drop each time you call the request, you should increase the value of "move"

Stap 3: Case

The case in this example is printed in PLA (Black and red), however other materials can be used to print it as well. The STL files can be found in the download at the bottom of this page. The components can be put in place by melting screw thread in the designated screw holes. This can be done for example by a hot soldering iron. I have also included a wall-mount to easily remove the food dispenser from the wall in order to refill the food-container

Stap 4: Electronics

The electronics of the NodeMCU and stepper motor should be wired like the following:

• D1 -> IN1
• D2 -> IN2
• D5 -> IN3
• D6 -> IN4
• VU -> 5V +
• GND -> 5V -