AI-powered autonomous control agent for the EMAX Nanohawk 1S FPV Drone.
A modular C++20 desktop application that uses a local LLM to interpret natural-language commands and fly the Nanohawk via the Betaflight MSP serial protocol. No FPV goggles required. Live camera feed streams to your desktop. You type a prompt; the agent executes it on the drone.
EMAX Nanohawk 1S -- https://emax-usa.com/products/nanohawk-1s-ultralight-brushless-fpv-drone
| Component | Spec |
|---|---|
| Frame | 65 mm brushless micro FPV |
| Flight Controller | STM32 running Betaflight 4.2.0 |
| USB Identity | VID 0483 / PID 5740 (STM32 USB CDC) |
| Serial Protocol | MSP V1 at 115200 baud |
| Motors | 0802 brushless, 4-in-1 ESC |
| FPV Camera | Analog + 5.8 GHz VTX (desktop capture via USB dongle) |
| Connection | USB-C to laptop (COM3) -- confirmed working |
DeviceWatcher automatically finds the drone at startup using two methods:
Sends NHAWK_DISCOVER (14 bytes) as a UDP broadcast on port 14560.
If a companion MCU replies with NHAWK_FOUND (10 bytes), its IP is used as the endpoint.
Scans the Windows registry for known USB device VID/PID combinations:
| VID | PID | Device | Baud |
|---|---|---|---|
0483 |
5740 |
STM32 Betaflight FC <- EMAX Nanohawk | 115200 |
2E8A |
000A |
RP2040 companion MCU | 500000 |
10C4 |
EA60 |
CP210x USB-Serial | 115200 |
1A86 |
7523 |
CH340 USB-Serial | 115200 |
0403 |
6001 |
FTDI FT232R | 115200 |
If no VID/PID match is found, falls back to sending an NHAWK? handshake on every open COM port.
| Layer | Role | Failsafe |
|---|---|---|
| LLM | Natural-language -> strict JSON | Returns idle JSON if unavailable |
| JsonPlanParser | Schema validation | Rejects malformed mission plans |
| SafetyEngine | Hard-limit veto | Blocks execution on any breach |
| AbortController | Operator emergency stop | Disarms immediately |
| MspClient.disarm() | Final hardware failsafe | ch[4]=1000, throttle=1000 |
| Manual TX | Physical radio override | Always available; takes precedence |
Key principle: The LLM never directly controls motors. It outputs JSON. JSON goes through safety validation. Only validated, operator-authorized commands reach the MSP serial layer.
- Windows 10+ (Linux/macOS stubs compile but lack Windows serial/WiFi backends)
- CMake 3.26+, C++20 compiler (MinGW-w64 or MSVC)
- Optional for GUI: Qt 6.5+, OpenCV 4.8+, libcurl 7.85+
Drone not detected
- Check Device Manager for
STM32 Virtual COM Port. - Use a data-capable USB cable (not charge-only).
- If COM port differs, update
endpoints.yaml->serial_port.
RC override has no effect
- Open Betaflight Configurator -> Receiver -> set type to MSP -> save + reboot.
LLM outputs prose instead of JSON
- Use an instruction-tuned GGUF model.
- Confirm
PromptCompileris injecting the mission schema.
Video shows no feed
- Check Device Manager for the FPV capture dongle (Imaging Devices).
- Try
uvc_index: 1or2inendpoints.yaml.
0xC0000139 on launch (MinGW)
- Rebuild via a CMake preset;
-static-libgcc -static-libstdc++is applied automatically.
Why MSP instead of MAVLink? The Nanohawk ships with Betaflight, which does not speak MAVLink. MSP is the native protocol -- lower overhead, simpler framing, direct RC override without firmware replacement.
Why local LLM? Privacy (prompts stay on-machine), low latency (~100 ms), no API cost, works offline.
Why not LLM -> motors directly?
LLMs hallucinate. Enforcing Prompt -> JSON -> Safety Veto -> MSP makes every command auditable, testable, and hard-limited before it reaches the hardware.
Why C++20?
Zero overhead on the serial framing path. Direct Win32 API access. No JVM or GIL. std::jthread keeps the pipeline clean.
- Set Betaflight receiver type to MSP in Betaflight Configurator.
- Download a GGUF model into
models\llm\and updateendpoints.yaml. - Run
nanohawk_device_detection.exeto confirm the full MSP session. - Run the CLI agent with a simple prompt to validate JSON -> MSP flow.
- Build the GUI (Qt6 + OpenCV) for live video and telemetry.
- First flight:
"Takeoff to 0.5 meters, hover 3 seconds, land"-- indoors, clear area.
Currently "Closed License".
This GitHub Repository is not currently sponsored by Emax USA - https://emax-usa.com/