A mini brushed DC quadcopter built entirely from scratch. No off-the-shelf flight controller software. Custom hardware, custom firmware, custom drivers.

• Overview
• Hardware
  • Drone
  • RC Controller
• Firmware
• Project Structure
• Build Status
• License

This project is a complete from-scratch implementation of a mini quadcopter and its RC controller. The goal is to understand and build every layer of the stack — from raw sensor data to stable flight — without relying on existing flight controller frameworks.

Key design decisions:

• Bare metal C using the Raspberry Pi Pico C/C++ SDK
• Dual-core RP2040: Core 0 handles flight control, Core 1 handles radio
• Custom drivers written from scratch for nRF24L01 and MPU6050
• No FreeRTOS, no MicroPython, no Betaflight

Power architecture:

• 1S LiPo (3.7-4.2V) direct to Pico VSYS
• Pico 3.3V rail powers nRF24L01 and MPU6050
• LiPo direct to TA6586 VM pins
• No external voltage regulators

AUW: ~67g estimated. Ceiling: 133g (1.5:1 thrust ratio).

Controls mapping:

Written in bare metal C using the Pico C/C++ SDK. Structured across three repositories:

Radio protocol:

• 12-byte packets at 100Hz default (configurable)
• 6 channels: throttle, yaw, pitch, roll, arm, flight mode
• Failsafe: motors cut immediately after 500ms signal loss
• Drone buzzer activates continuously on signal loss for crash location

Dependencies:

• pico-ssd1306 — OLED display

init-flight-stack/
├── drone/
│   ├── src/
│   └── include/
├── controller/
│   ├── src/
│   └── include/
└── docs/

Structure will be populated starting Phase 2.

MIT License. See LICENSE for details.