Integrating Custom Script with iNav for SITL Testing on a Quadcopter

[nikita-noteunlimited]

Hello INAV community,

I'm currently in the process of developing an autopilot system for a quadcopter, with the decision-making software running on a Jetson Nano. My primary objective is to have the quadcopter react in a simulator based on commands sent from my script.

While I've found materials on how to use iNav with manual remote control in SITL and HITL environments, particularly with RealFlight or X-Plane, I'm unsure about the integration process for my specific needs.

My key questions are:

1. How can I configure iNav to accept commands from my script (on the Jetson Nano) in a simulated environment?
2. Are there any recommended practices or existing frameworks for sending commands to iNav such that the simulator (like RealFlight or X-Plane) reacts to them?
3. Is there any documentation or tutorial that can guide me through the setup process of connecting my script with iNav in an SITL or HITL environment?

Any insights or guidance on this topic would be greatly appreciated. Thank you in advance!

Best regards,
Nikita Yeryomin

[RomanLut]

1. Neither HITL nor SITL support quadcopter simulation. The only supported platforms so far are Aiplane/Flying wing.

2. The question about inav <-> external device communication is unrelated to HITL,SITL, Realflight and X-Plane.

In general, you have to configure flight controller to accept Multiwii Serial Protocol (MSP) on some UART, then communicate via this UART to request or set states.

INAV is simple self-contained firmware for enthusiasts. Not many people developed systems where flight controller with INAV firmware is controlled by the exernal device.

If you search, you can find some MSP libraries though, not widely used:

https://github.com/christianrauch/msp

https://github.com/alduxvm/pyMultiWii

3. Unfortunatelly INAV internals are not documented, including MSP protocol. If you want to program for INAV, you have to study source code, in particular - how INav configurator communicates with FC.

[nikita-noteunlimited]

Hi @RomanLut ,

Thank you for your insightful response.

1. I appreciate the clarification regarding the current state of SITL and HITL only supporting the Airplane/Flying wing. This setup aligns with my needs, as I aim to develop higher-level logic for the autopilot using this framework.

2. With the use of pyMultiWii, I've successfully established communication with my board running INAV and can retrieve telemetry data with ease. While I can transmit RC commands from my script to the board, it's challenging to gauge the effectiveness of these commands, particularly when the motors remain inactive, and the drone is stationary. Therefore, I contemplated utilizing a simulator to visually ascertain if the drone moves in the anticipated direction on the map.

I also have a query about the potential of integrating the MAVLink protocol in lieu of, or alongside, MultiWii for various logical components. However, my immediate concern revolves around constructing a setup where I can witness the drone's movement in the simulator upon dispatching commands to INAV.

Thank you for your time and assistance.