In 2013, I attempted to build a programmable robot toy to help teach kids how to code. The idea: a small two-wheeled robot that a child could control by writing simple programs on a connected computer, giving immediate physical feedback as their code runs.
It did catch on fire a little bit.
The robot communicates with a host computer over Bluetooth using a simple bracket-delimited message protocol. The host sends commands (e.g. move at a given speed), the robot executes them and responds with sensor state. The goal was to keep the protocol simple enough that a beginner could understand and extend it.
Hardware features:
- Two DC motors with wheel encoders and PID speed control
- Front, left, and right bump sensors
- IR proximity sensor
- LED "eyes" with PWM brightness control
- Bluetooth serial link (288000 baud)
- AVR microcontroller running at 14.7456 MHz
eagle/ — PCB schematic and component library (EAGLE)
embedded/ — AVR-GCC firmware (C)
python/ — Host-side test script (Python 2, Bluetooth serial)
Messages are bracket-delimited ASCII strings sent over Bluetooth.
| Command | Format | Response | Description |
|---|---|---|---|
| Get state | [GS] |
[FLRIIII] |
Bumper events (F/L/R) + IR value (hex) |
| Move | [MVLLMRRS] |
[OK] |
Left speed + direction, right speed + direction |
Bumper event characters: L = low, H = high, F = falling edge, R = rising edge.
From the embedded/ directory:
mkdir build
cd build
cmake -DCMAKE_TOOLCHAIN_FILE=../avr-gcc-toolchain.cmake ../Then to build and upload:
cd build
make upload_robogramThis was a prototype/exploration. The movement command is stubbed out in firmware and the Python script is a latency benchmark over Bluetooth rather than a finished interface. The project was shelved before reaching a child-facing programming environment.