Companion computer to fly in guided mode without GPS

Hi all,

I am developing a companion software that takes control of a drone while it is flying.
I want to navigate the drone in guided mode (with NED coordinates) without any consideration of GPS.

Is there any way to use NED coordinates in a guided no GPS mode?

Hope you can help me with that.
Thanks,
Yoni

You need to add https://github.com/ArduPilot/ardupilot/pull/15854 on top of master, recompile the code and upload to the vehicle

Can you please explain how I can control a drone in auto mode?

My bad, for real time control using a companion computer you do need “guided no GPS” mode.

You can start here: https://ardupilot.org/copter/docs/indoor-flying.html

continue here:

and here:

Thanks for replying. This looks interesting but I am looking for a solution without a camera.

Do you know about any solution that might help me?
I need to navigate the drone with NED coordinates without consideration of GPS and without any additional tools (using only MAVLink)

You will need some sort of GPS replacement: beacon or optical flow otherwise it won’t work.

You could use stabilize flight mode a give joystick commands. But that is a huge hack!!!

As @amilcarlucas says, you need some other sensor to estimate the position of the drone. Without GNSS or any replacement can’t the drone know its position. You can find some replacements here: https://ardupilot.org/copter/docs/common-non-gps-navigation-landing-page.html. I think optical flow is the easiest if you are flying indoors, but that will also have some drift.

There does exist a Guided NoGPS mode, but then you can’t send NED coordinates, only attitude targets.

Thanks a lot for replying.

In Guided NoGPS mode, is there a way to know the speed of the drone?

No, there is not. You need some suited sensor to be able to measure the speed, e.g. those mentioned in my previous answer. GNSS is the most common, but if you are indoors I think optical flow is the easiest.

You could theoretically try to estimate the speed from the IMU readings or try to simulate the movements from the propeller thrusts in a dead reckoning scheme, but that will be prone to drift and difficult to implement. It is more normal to consider speed unobservable without more sensors.