DIY Radio Controller (Arduino)

A compact, 3D-printable RF joystick controller for ShunkoBot and compatible robots.
The controller features:

• Analog joystick for robot movement
• Action buttons to control the end-effector
• 2 shoulder buttons to enable rotation in omnidirectional robots
• 3 potentiometers to control the three joints of a robotic arm

This module provides 3D models, Arduino firmware, wiring, and command references.

Repository Structure

• controller_3Dmodel/ — SolidWorks models (.SLDPRT, .SLDASM)
• controller_3Dmodel/printable_files — Printable files (.stl), STL files
• controller_code/ — Arduino code, configuration and transmitter sketches, prototype image

Features

• MCU: Arduino Nano
• Radio: HC-12 433MHz UART
• Controls: Analog joystick, digital buttons, 2 shoulder buttons, 3 potentiometers
• Power: LiPo battery
• Protocol: UART (Serial)

3D Model

• Main files:
  • Base.STL, front_cover_part.STL, back_cover_part.STL, button_part.STL, button_cover.STL, shunko_txt.STL, arrow.SLDPRT
  • Assembly: controller_ass.SLDASM
• Drawings and SVGs:
  • svg/Draw1.SLDDRW, svg/Draw2.SLDDRW, freccia-2820191500.svg, shunko_txt.dxf
• Recommended print settings:
  • Material: PLA/PETG
  • Layer height: 0.2mm
  • Infill: 20-40%
  • Supports: Only for covers and buttons
• Assembly notes:
  • Follow the SolidWorks assembly for mounting.
  • Fix the Arduino Nano board to the base with M2 screws.
  • Insert the HC-12 module into its dedicated slot.
  • Connect joystick, buttons, and potentiometers according to the wiring diagram.

Wiring

• Pinout summary:
  • HC-12 Radio:
    • VCC → 5V
    • GND → GND
    • TX → D11
    • RX → D10
    • SET → D5 (with jumper NO)
  • Analog joystick:
    • VRx → A1
    • VRy → A2
    • SW → A3
  • Buttons:
    • trn_L → D8
    • trn_R → D9
    • leftE → D3
    • rightE → D2
  • Potentiometers:
    • POT1 → A4
    • POT2 → A5
    • POT3 → A6
  • Power:
    • Vin → 7.4V battery
    • GND → GND

Additional assembly notes:

• The back cover allows installing a LiPo battery, a TP4056 charging module, and a slide switch to cut power. This makes the controller portable.
• For assembly, you must create a custom PCB on perfboard (millefori) and solder all components as per the wiring diagram, using an Arduino Nano.
• To secure the assembly, use four M3 screws (20–30 mm) with plastic inserts mounted in the front cover.

Firmware

Configurator

Arduino IDE:

1. Open controller_code/HC12_configurator/HC12_configurator.ino
2. Select Board Arduino Nano, Port <COMx>, and Processor "ATmega328P (Old bootloader)"
3. Upload
4. Enter AT mode: keep SET pin LOW (pin 5 LOW).
5. Configure at 9600: HC12.begin(9600); HC12.println("AT+B115200"); expect “OK+B115200”.
6. Switch to 115200 and exit AT: HC12.end(); HC12.begin(115200); digitalWrite(5, HIGH);
7. Normal run: Serial.begin(115200); HC12.begin(115200);

Transmitter

• Required libraries:
  • HC12
  • CRC32

Arduino IDE:

1. Open controller_code/HC12_transmitter/HC12_transmitter.ino
2. Select Board Arduino Nano, Port <COMx>, and Processor "ATmega328P (Old bootloader)"
3. Install libraries listed above
4. Upload

License

ShunkoBot © 2025 by Francesco Stasi, Davide Tonti, Simona Vatinno is licensed under Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International.