QuadRanger support

#1

A new QuadPlane build instruction is online: http://px4.io/docs/quadranger-vtol/
Go and build one and post any questions here. We are happy to assist you in building and configuring your QuadRanger.

pinned #2
#3

Hello, I’m building and quadplane based loosely on the Quadranger build here, the only real difference is I am using 8 motor’s like an x8, and I plan to add the pixhawk2 when it arrives.
I have had one test flight. it lasted about 2 seconds.I could never figure out motor assignment in arduplane with mission planner.
My question: Is this configuration supported in px4 and if so what are the motor pin assignments?

#4

an X8 quad configuration for VTOL is not yet provided standard but is relatively easy to add as a mixer.
Just add a custom mixer file to your SD that you copied from the standard mixer and change X4 to X8

1 Like
#5

@sanderux,

I saw in the menu that Aux1 and Aux2 used for left aileron and right aileron separately.

I try to use 1 servo for both left and right ailerons.

Is it possible to use just 1 aux output for 1-servo aileron config?

Thanks.

#6

@sanderux I maidened my Ranger-EX today in FW manual mode, and found that I need nearly 50% up elevator for level flight at about 70% throttle (4S, 6600mah LiPo, 10x6 prop).
That’s with the CG at the recommended 62mm from the leading edge. Seems like it needs to move way back to get elevator trim closer to zero. Where do you have the CG on the QuadRanger?

#7

I had the CG a little more back then 62mm, but not much. are you sure your ailerons are level?

#8

The ailerons are mechanically centered at zero deflection.

#9

do you have a log? …

#10

here’s the log: http://logs.uaventure.com/view/cYQpYgHCvaS4wtYHP6HC5V
There’s some level flight from 190 to 215 seconds elapsed, then the landing. Plane flew well, didn’t need much roll trim. But the motor was too loud at high throttle. Not sure what’s causing that; the prop is balanced and the mount is solid. Need to check current draw with an external meter; my power module wasn’t set up correctly.

#11

on what channel is your elevator (main out port number)

#12

elevator output is main 1, RC input is channel 2

#13

do you have a lot of deflection on your elevator?
by the way, your airspeed sensor is very off.

#14

The elevator throw is what the manual recommended, and it felt about right in manual mode, just way out of trim. I’m not sure I trust the GPS velocity either. Both agree on the final approach, and GPS seems to be way off when pitch angle is large.

#15

Do you have any logs with 45 degree pitch descents?

#16

both gps and accelerometer read much higher speed
i would indeed conclude your CG should be further back.
carefull not to put it too far back, i still wouldnt rule out another cause

#17

The vibration looks very high at high throttle, right? I’ll try a different prop.
High vibration could also corrupt any accel based velocity estimate.
Also, it looks like logmuncher’s thrust/mag plot is broken; no thrust curve.

#18

it does.
your gps groundspeed (based on x and y,not z) would only be lower, not higher, its higher.

#19

agreed, airspeed should have been higher than groundspeed on final (into the wind) and it isn’t.

#20

I have a question about frame setup. My quadranger has booms for lift motors parallel with fuse just like the build here. what frame layout should I use? H or X? Also, would you please explain the difference to me?