hi,
i’m unable to get a RTL mode to work with my dolphin VTOL 4s.
my parameters : bit 16 in Q_OPTIONS NOT on ( 688160)
Q_RTL_MODE :1
RTL_RADIUS : 20
Q_RTL_ALT : 15
When i choose RTLmode, the plane makes a u turn and after that goes to VTOL mode( the plane is unable to stabilizise ) and i have to go back to Qhover.
i don’t understand why the plane do not come back to the launch point in fixed wing mode : i’m at 70 meters, at 100 meters high …
i need help !
thanks
Hi, I don’t see any anormal behavior here. You have Q_RTL_MODE = 1 so the drone, after RTL, will perform airbrake and switch to QRTL when approaching the home point.
Note that you have Q_TRANS_DECEL = 1 m/s/s and your airspeed is 20 m/s, so it takes 20s to stop your drone, if you’re too close to home (distance is less than stopping distance) than it will switch immediately to QRTL. If you’re far from home point, you will stay more time in RTL Mode.
If you want a fixed wing landing I think you need to disable Q_RTL_MODE and try to set up RTL_autoland instead. You can try to change those params in SITL to make sure you have no surprise when flying
Thanks for the answer !
I’m testing the Q_Rtl before going far .. that the reason why i’m so close .
A way to get the switch to QRTL Nearer would be changing the Q_TRANS_DECEL paramétrer to 2 ?
But my fear is that the plane can’t make the transition : if you look at the ardupilot log viewer you can see that the transition fails( in q_RTL ) . I have to save the plane going to Q_Hover …
another demand : i understand the argument : 20 m/s, 1m/s airbraking = 200 meters.
but it’s strange that the plane make the transition at 100 meters (distance) , i expected that the transition was made at 20 meters .
I think (can’t be sure) that because you have d=341m (distance) and sd=406m (stopping distance) it needs to go vtol
hi,
d and sd are not parameters, could it be possible that i have a problem with my gps ?
the informations from the GPS seem to be accurate …
Had a similar issue with a plane transitioning from RTL to QRTL far outside the set radius. While it seems unrelated, disabling harmonic notch filtering resolved the issue. Can’t really explain it.
I can’t believe that turning off the notch filters is the solution. Anyway.
Is there anyone here who can explain how the Q_TRANS_DECEL parameter can be determined? Or does the rule here apply that you increase the value until no overshoot is displayed?
It’s not. Most likely coincidental in the case described. Don’t do that.
For the code to judge when to start the transition to VTOL in order to arrive at the point it should be totally VTOL, the Q_TRANS_DECEL parameter is used to calculate the when to start the transition. If the vehicle is overshooting, this value can be lowered, and vice-versa.
hi,
right for me the problem was Q_TRANS_DECEL. the parasmeter was 1 , i put 2 and this resolved the problem. it seems that the airplaine do not have the time to make the transition because the home position is too close ,
