I just tried using the GUIDED_NOGPS mode in SITL. It works pretty fine with GPS and compass enabled. However, if I turn GPS and compass off, it seems to work but does not show me the copter on the map. Therefore, I set the origin to some GPS coordinate and after that I only get EKF variance errors and the copter does immediately change to LAND mode. Now, I was wondering what the exact requirements for the GUIDED_NOGPS mode are. I thought it does neither need GPS nor compass.
I want to fly without any positioning and by only providing roll, pitch and yaw angles or velocities to move the copter. When I provide nothing, the copter should just hover. Do you know if there is any possibility for that?
Thanks @mlebret for the quick reply.
Of course I used those. I’ve forgotten to mention that I want to have an autonomous flight but without external positioning, like GPS or optical flow. The reason is that I have a positioning system (only position) which I want to employ. It is very precise but the connection is not so stable and if I try to use normal positioning modes the copter may be uncontrolled if I do not provide position any more.
I’m afraid that is not possible with the pixhawk hardware. The accelerometers and gyroscopes are consumer grade sensors, so their error rate not good enough for navigation._
_With some fiber optic gyros or “tactical grade” mems sensors (www.analog.com/en/products/adis16485.html) it could be possible with only a couple meters error, but not for long time, and the price of these are in the 1-10k usd range.
@mlebret thanks, I am developing an application similar with @xfly. I want to fly in a AC room there are lot of fracture of barometer value . I think Altitude Hold could not work properly in AC room or cloudy weather. So i used rangefinder (maxbotix). But did not fly properly. I used a very basic script that puts the drone to GUIDED_NOGPS mode, armed it and forces it to takeoff for the altitude say 1m, then it straight up for a while and lands. When i armed then it takeoff then drone going straight up. Did not stay in 1m altitude.
Not sure about your exact control but I learned some time ago that GUIDED_NOGPS mode also uses GPS and Barometer values, same as GUIDED. So this may be the reason that your drone did not hold its altitude.