So i’m running the ArduCopter 3.6 RC-11, and having this weird issue where my copter keeps climbing in altitude even when i have set the waypoints to be of only 27m height? I will be attaching the log files as well as the waypoint file. I have tried to see if there are any errors, but so far, I’m not able to find any issues as far as I can see. Even downgrading the firmware does not help as by downgrading, the Pixhack only shows one internal compass(does not detect the other 2 compasses) even when it has 2 internal and one external connected to it. Please help.
Vibration levels are far too high I’m afraid. Perhaps there’s no vibration dampening on this vehicle?
The levels can be seen in the VIBE message’s VibeX, VibeY, VibeZ fields and the Z-axis is regularly above 60m/s/s. A normal vibration level is about 15m/s/s and we recommend that the frame be such that levels are below 30m/s/s (some occasional spikes above this is fine).
They grey zone is from 30m/s/s ~ 60below where altitude control might work but might not.
Above 60m/s/s we very regularly see the EKF get confused about it’s altitude and so the altitude hold doesn’t work well.
Thank you so much. It solved the problem almost immediately. I never did bother putting any dampeners as the pixhack was internally dampened. Shows just how much more I have to learn.
If I may ask another question, I have flown today in Auto again, but while going to a waypoint, my copter pitched 90 degrees. I immediately changed to RTL and saved the drone. While checking the logs, I noticed that one RCOUT was very less compared to the other three, and auto analysis of logs said that the motors balance has failed? Does that mean that the motor is not working properly?
It’s hard to be sure unless I see the logs but it certainly could be an ESC or motor failure. Another possibility is that the ESCs haven’t been calibrated so an output from AP can cause the motor to stop because the range the ESC is expecting doesn’t match the range the flight controller is outputting. This is a guess of course… it could be a number of other things as well.
If you don’t mind. I have attached the log file in this comment. Please check it, I have calibrated the ESCs using the manual, one at a time and automatic calibration method. But still see that the 3rd ESC seems to not take the same pwm range? I have changed the motors too, and got back the same results.
The ESCs I use are Flightline BLHeli 40amp ESCs. I have tried to do the BLHeli passthru, but not once has any of the ESCs gotten detected. If any suggestions, I will be grateful. Thanks again!!!
This vehicle looks to be flying 3.5.7… so really this doesn’t really belong in the 3.6.0 release thread.
It may not be an issue with motor3 actually. The output to that motor is very low because the attitude controllers have found that it doesn’t need that motor much. It is actually more likely to be an issue with some of the motors not being straight, the center-of-gravity of the vehicle is very far off… or perhaps a combination of issues like this. It’s actually kind of surprising that it flies at all. I’m not sure I’ve ever seen a vehicle with a single motor this far from the rest and still have it flyable.
… another possibility is that the ESCs are misconfigured… so for example is motor3’s ESC was configured so that it can spin backwards we might see something like this… it’s pretty unusual but I don’t think it’s an AP software issue. It’s almost 100% an issue with the frame.
So Sorry for the logs. I didnt mean to send the wrong one.
I just wanted to clarify that it was the ESC problem from the logs as I’m still earning how to use logs for better analysis of the flights my drone has flown. Thank you so much for such a quick reply.
The frame is a s500 frame, so the motors are slightly tilted by a few degrees inwards. As for the center-of-gravity, I check it every time before i take off, as it is part of my pre-flight checklist.
I did try the BLHeli passthru, but it could not connect to even one ESC, so I think its the ESC too. Thanks a lot again.
If i may ask, is there any documentation on how to read logs so that you can understand the problems in the drone? If yes, could you please give the link so that I may learn more.
