ArduCopter: Spline + DO_JUMP = Crash ?! Possible BUG


Some weeks ago I had a crash with my tricopter (3.2RC9), using Pixhawk.
Basically I wrote a small mission flying through an “8” shape and then repeat it with DO_JUMP.
During the second round, once copter started to accelerate, I heard some sound signals from Pixhawk and I then lost any control. (Log, mission, parameters are in the folder below).

Today I was flying with my newly built quad (3.2RC14), made a sample mission that was quite similar to the one in the tricopter (“0” shape from 8 spline waypoints and DO_JUMP at the end). During the second round I had exactly the same issue, Pixhawk made some sound signal, copter started to accelerate and I couln’t control anymore till hit the ground (tried to switch back to stabilize or loiter w/o success). Unfortunatelly I didn’t have any logs now because battery was disconnected during crash. (Parameters, mission file are in the folder below)

So it quite looks like spline waypoints and DO_JUMP together causes total Pixhawk breakdown.

I’ll not try spline WPs again until this BUG or explanation are found… hope you understand.


All files can be found here: … sp=sharing

I forgot to mention, controller is a Pixhawk.

Could anybody test 3.2 RC14 with a similar mission? (7-8 SPLINE Waypoints and a DO_JUMP at the end for repeat mission at least 5 times).

Many thanks.

only the “tricopter crash” had any useful data (.bin) , no log for the other.
The tricopter was clearly unable to maintain roll - plot ATT.Roll va Att.DesRoll , and you will see a big difference - that gave the speed increase.

A typical sign of mechanical failure, ESC, or anything that could result in less thrust than needed, or in this case, even a servo error. - you can see yaw is also going outside desired area.

All I am unsure of, is the PWM and servo output - must assume it’s normal, on a more-than-tricopter I would expect one motor go much higher/max out before deviating that far from desired attitude, but the method is cannot be the same on a tricopter, as it’s power is not symmetric in all directions/axes.
Take that with a grain of salt, I am not really familiar with tricopters, as it’s not exactly a reliable design.

What’s clear: is that it failed to maintain attitude.