Just had my third major crash in two weeks. This time took out 4 props and my receiver ....
I think that I at last understand the problem.
I have been really keen to use RTL and up to and including .37 it has been unusable for me. The model would fly off at 45 degrees etc and the first two crashed were when I switched back to stable mode.
Today on .38 the RTL function was at last working for me - fly the model 100 metres away and then watch it come back to RTL position, a little meandering but other that than excellent.
On my third battery I tried RTL again and when it comes over my head I switch back to stable mode and just like the last two crashes, the hexa does a 180 and goes in under full power.
All three crashes, now with .37 and .38 happened when I switched from RTL to stable. To do this I move my two and three position switches through Alt_hold back to stable. I think the problem is that I am confusing the program by going between two or three modes in a split second.
Would anyone agree that this may be a problem and if so is there a way to ignore new mode for perhaps half a second.
Must say that before the crash this evening, I had the most fun in ages with Altitude hold, Loiter and RTL all working really well.
Crap, That doesn't sound good and no I don't know right away what the problem is. Is the 180 a yaw or did it flip upside down? Do you have a log? What was your throttle position when it happened? Was the copter relatively still when you switched or was it moving?
Hi Jason - when switching back to stable mode with the hexa at about 3 metres off of the ground, it suddenly flipped upside down and then powered in to the ground. I can see that it may have been caused if I'd had full throttle when leaving RTL mode but I'm sure that wasn't the case. As it flips my first action is to drop throttle to zero by putting left stick to bottom left. I can't believe how hard it hits the deck from such a low altitude.
I have a strong aluminium arched bar over the top of the model and the IMU is housed in a strong plastic case. When I picked up the model, the aluminium bar was flatted on top on the plastic case which had been smashed. To say this happened on grass - it was an amazing amount of force. I'm sure the throttle must have been up quite high. - Sorry no logs.
If this is a mode change bug, then it should not trig when switching directly from RTL to stable. (can be tested setting only two modes : stable and RTL).
If this is really a mode change bug, i think that a mode change sequencer should be designed, so that mode changes cannot corrupt some variables. The sequencer would check that all is ok before mode changing, and delay the mode change until all conditions are ok.
I also tried RTL with v37 but only had to change one position to go from RTL to Stable. Had to do this because quad was flying aggresive.
My modes are
pos 0 stable
pos 1 RTL
pos 2 AH
pos 3 Simple
pos 4 Loiter
pos 5 Auto
does it again yaw problem on this news version?
days after days,arducopter become better but apparently it s far to be perfect!!
To be fair to our unpaid development team, a bug can't be addressed until it is discovered.
I don't regret the hundreds of pounds that this project has cost me so far - it has been an all consuming obsession and if I could buy a finished version in the high street, I probably wouldn't want it..
Agree on this one, and I think we do our part as beta testers and search for this imperfections. At times it can be frustrating but someone has to do it :D.
On the switching of modes I have almost similar setup as with you I go from RTL --> ALT_HOLD --> STAB but the only thing that happened was increase power on motors which made the quad go up, I still ended up crashing I hit the tree branch, I miscalculated the distance (quite dark cause I was flying at night). Anyway, I didnt noticed the flip over behavior. I guess I would know tomorrow as I am about to test v38
ahahahah same here even if I'm closer to bankrupcy more than ever :) team development is all about that.
My thinking right now is that there is some sort of I term windup causing the flip that combined with some gyro drift and a powerful setup could cause a flip in the worst circumstances. Theoretically. I haven't run the numbers but a log would be awesome if you had one.
Agreed. Please post logs!
Mine was already deleted as I knew it was pilot error but if I see the same behavior tomorrow I will post the log. But maybe Philip still has his logs