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iNavFlight / inav

INAV: Navigation-enabled flight control software
https://inavflight.github.io
GNU General Public License v3.0
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Inertial Navigation System #4149

Closed EnsignCrasher closed 5 years ago

EnsignCrasher commented 5 years ago

Hi Guys, can someone tell me if there is some functionality in iNAV like a GPS-aided inertial navigation system? To keep track of an estimated position if GPS would somehow fail for some time?

shellixyz commented 5 years ago

It does position estimation but in case of GPS failure the position estimate is not trusted and it will execute an emergency landing.

imrj commented 5 years ago

INS navigation is primary navigation system on real commercial aircraft, not GPS...that being said you are asking for a lot and requires very accurate sensors (I think Boeing uses like 3 independent redundant INS systems)....but I think they are working on something over on the ardupilot software for navigation w/o GPS... http://ardupilot.org/copter/docs/common-pozyx.html

digitalentity commented 5 years ago

INAV is built around inertial position estimation (just like big aircrafts), however quality of sensors and conditions we're flying in are quite different, so raw estimate is only trusted for a few seconds to cover very short GPS gaps.

EnsignCrasher commented 5 years ago

Thanks for the quick responses! So if I got that right, when gps signal is lost, inav will perform an emergency landing after a few seconds... Is there any way to keep it flying anyways? Maybe with nav cruise or anything like that?

teckel12 commented 5 years ago

@EnsignCrasher It depends on how you set failsafe.

EnsignCrasher commented 5 years ago

Ah okay, so failsafe gets executed on GPS failure hm? Is that always the case or just for autonomous flight modes that require GPS? Wouldn't make much sense if you are just flying in angle mode and suddenly it triggers failsafe because of GPS failure...

shellixyz commented 5 years ago

@teckel12 It doesn't depend on the failsafe settings.

@EnsignCrasher It will only execute an emergency landing if you lose fix when you're in a mode that relies on the GPS position (RTL, POSHOLD, WP). By default after 5s (nav_position_timeout setting).