Shadow-RC is a highly customizable, real-world control system for R2-D2 droids. Built on the Arduino Mega 2560 platform, it uses dual 6-channel RC controllers, Sabertooth and SyRen motor drivers (via packetized serial), and optionally supports MP3 playback and full MarcDuino integration.
The system includes four operational modes, a robust 32-slot combo trigger system, joystick flick detection, dome automation, and full parameter tuning. Shadow-RC is ideal for builders who want a reliable, analog-feeling droid control system with flexible expansion.
- Manual Mode – Responsive, direct joystick control of drive and dome
- Carpet Mode – Boosted drive power for navigating carpet and rough terrain
- Hybrid Mode – Adds dome automation and ambient sound to manual drive
- Automated Mode – Fully autonomous dome movement and sound (no RC input)
- Combo System – 32 joystick + button combos for triggering sounds, lights, servos, or MarcDuino actions
- MP3 Support – Supports SparkFun MP3 Trigger and other serial MP3 boards
- MarcDuino Support – Optional integration for screen, lighting, and panel control
- Fully documented – Includes full pinout, tuning guide, combo sheet, and builder's manual
- Arduino Mega 2560
- 2x 6-Channel RC Receivers + 2x RC Transmitters (e.g., FlySky, HotRC)
- Sabertooth 2x32 motor controller (drive)
- SyRen 10 motor controller (dome)
- SparkFun MP3 Trigger (or supported serial MP3 board) (optional)
- 5V regulated power for Arduino + receivers
- 12V+ power supply for motors
Drive Controller (A):
- CH1 → Pin 2 (Turn)
- CH2 → Pin 3 (Forward/Reverse)
- CH3–CH6 → Pins 22, 24, 26, 28
Dome Controller (B):
- CH1 → Pin 21 (Dome Turn)
- CH2–CH6 → Pins 23, 25, 27, 29, 31
Serial Outputs:
- TX1 (Pin 18) → MP3 Trigger RX
- TX2 (Pin 16) → Sabertooth & SyRen S1 line (daisy-chained)
- TX3 (Pin 14) → MarcDuino RX (if used)
Sabertooth 2x32 (Drive Motors):
[OFF OFF ON ON ON ON] → Address 128, Packetized Serial Mode
SyRen 10 (Dome Motor):
[OFF OFF ON OFF ON ON] → Address 129, Packetized Serial Mode
- Open
Shadow_RC_v1.0.inoin the Arduino IDE - Select Board: Arduino Mega or Mega 2560
- Select the correct COM port
- Upload the code to your Arduino Mega
- Power on the droid — the onboard LED (pin 13) will blink to indicate the current mode:
- 1 Blink = Manual Mode
- 2 = Carpet Mode
- 3 = Hybrid Mode
- 4 = Automated Mode
| File / Folder | Purpose |
|---|---|
/Documentation |
Builder’s Guide, Quick Start, Combo Sheet, Tunable Parameters |
/Libraries/Sabertooth |
Sabertooth library used for motor control |
ManualMode.cpp |
Code for direct joystick drive + dome control |
CarpetMode.cpp |
Enhanced drive for carpet and high-friction terrain |
HybridMode.cpp |
Drive + dome automation + MP3 ambient |
AutomatedMode.cpp |
Fully autonomous dome and sound |
ComboHandler.cpp |
All 32 joystick+button combos mapped here |
MP3Handler.cpp |
Sound playback logic and category mapping |
PWMInputHandler.cpp |
Interrupt-based PWM reader for all RC channels |
| Category | File Range |
|---|---|
| Happy | 001–016 |
| Sad | 031–035 |
| Talking | 061–076 |
| Yelling | 091–103 |
| Classic | 121–123 |
| Dance | 151–156 |
| Singing | 181–186 |
| Lines | 211–212 |
(You can update these ranges in MP3Handler.cpp to match your SD card setup. MP3 filenames must use the format ####.mp3, e.g., 0061.mp3.)
- 32 unique combos triggered by joystick direction + opposite controller button
- CH3–CH5 are toggle switches (trigger on any state change)
- CH6 is a momentary button (trigger only on rising edge, ~1988 µs pulse)
- Combos 1–4 = Mode Switching
- Combos 5–8 = MarcDuino Mode Commands
- Combos 9–20 = MP3 categories
- Combos 21–32 = Available for custom use
Refer to the Combo Reference Sheet for the full map.
This project is open-source for personal use and educational purposes. Attribution is appreciated. Please credit the Shadow-RC project if adapting or sharing.
May the Force be with you, Builder.