Went to do a survey mission with our quadcopter today. Conditions weren’t too ideal with wind gusts of 20-25 mph, but we had tested previously in those sorts of conditions and it performed OK. The mission was going smoothly until the last couple of waypoints when the drone started gaining altitude like crazy. An attempt was made to land the drone at around 300ft. It started descending, but then continued to climb even higher. It ended up reaching >500ft in altitude and “toilet-bowling” before crashing some ways away.
[quote=“swagFault”]Went to do a survey mission with our quadcopter today. Conditions weren’t too ideal with wind gusts of 20-25 mph, but we had tested previously in those sorts of conditions and it performed OK. The mission was going smoothly until the last couple of waypoints when the drone started gaining altitude like crazy. An attempt was made to land the drone at around 300ft. It started descending, but then continued to climb even higher. It ended up reaching >500ft in altitude and “toilet-bowling” before crashing some ways away.
[quote=“BigTulsa”][quote=“swagFault”]Went to do a survey mission with our quadcopter today. Conditions weren’t too ideal with wind gusts of 20-25 mph, but we had tested previously in those sorts of conditions and it performed OK. The mission was going smoothly until the last couple of waypoints when the drone started gaining altitude like crazy. An attempt was made to land the drone at around 300ft. It started descending, but then continued to climb even higher. It ended up reaching >500ft in altitude and “toilet-bowling” before crashing some ways away.
Do you not have access to the .bin/.log file? Is the vehicle completely lost?[/quote]
I do have a .log dataflash file, forgot to post it earlier. Here it is
[quote=“swagFault”]Couldn’t figure out for the life of me how to attach the log to the post so here is the hosted link: 2015-10-02 09-18-56.log[/quote]
At an initial glance I’m noticing:
As you alluded to, the magnetic interference is quite bad. Where is the GPS mounted on this vehicle? Do you have it elevated or is it on the frame somewhere? Have you tried to run compassmot/Extended Compass calibration? This is where you either reverse the props or strap the vehicle down, start the test and run the throttle up 70 to 100 percent for 5 seconds or more.
Your IMU vibrations are out of spec. How do you have the FC mounted? Foam? On a plate with rubber dampers? Both?
I saw some EKF errors, which will likely happen when you have magnetic interferences this big.
That’s about all I can start off with. I"m still a bit of a rookie when reading these but I’ve had a bunch of experience reading them now.
[quote=“BigTulsa”][quote=“swagFault”]Couldn’t figure out for the life of me how to attach the log to the post so here is the hosted link: 2015-10-02 09-18-56.log[/quote]
At an initial glance I’m noticing:
As you alluded to, the magnetic interference is quite bad. Where is the GPS mounted on this vehicle? Do you have it elevated or is it on the frame somewhere? Have you tried to run compassmot/Extended Compass calibration? This is where you either reverse the props or strap the vehicle down, start the test and run the throttle up 70 to 100 percent for 5 seconds or more.
Your IMU vibrations are out of spec. How do you have the FC mounted? Foam? On a plate with rubber dampers? Both?
I saw some EKF errors, which will likely happen when you have magnetic interferences this big.
That’s about all I can start off with. I"m still a bit of a rookie when reading these but I’ve had a bunch of experience reading them now.[/quote]
Thank you for your reply! The weird part of this whole thing is that the drone didn’t start acting up until almost the very end of the mission. Also, can’t seem to find any data in these logs that would explain why it started climbing uncontrollably. But, to answer your questions:
The GPS is mounted on a ~3 inch tall 3D printed stand that sits on the frame, so yes, it is elevated. I haven’t tried running compassmot yet since it didn’t look like we had major problems with interference during previous flights. That’s on the list now…
The FC sits directly on the frame’s centerplate and is held using 3M VHB tape. You mentioned IMU vibrations. What are they and where did you find that parameter?
[quote=“swagFault”][quote=“BigTulsa”][quote=“swagFault”]Couldn’t figure out for the life of me how to attach the log to the post so here is the hosted link: 2015-10-02 09-18-56.log[/quote]
At an initial glance I’m noticing:
As you alluded to, the magnetic interference is quite bad. Where is the GPS mounted on this vehicle? Do you have it elevated or is it on the frame somewhere? Have you tried to run compassmot/Extended Compass calibration? This is where you either reverse the props or strap the vehicle down, start the test and run the throttle up 70 to 100 percent for 5 seconds or more.
Your IMU vibrations are out of spec. How do you have the FC mounted? Foam? On a plate with rubber dampers? Both?
I saw some EKF errors, which will likely happen when you have magnetic interferences this big.
That’s about all I can start off with. I"m still a bit of a rookie when reading these but I’ve had a bunch of experience reading them now.[/quote]
Thank you for your reply! The weird part of this whole thing is that the drone didn’t start acting up until almost the very end of the mission. Also, can’t seem to find any data in these logs that would explain why it started climbing uncontrollably. But, to answer your questions:
The GPS is mounted on a ~3 inch tall 3D printed stand that sits on the frame, so yes, it is elevated. I haven’t tried running compassmot yet since it didn’t look like we had major problems with interference during previous flights. That’s on the list now…
The FC sits directly on the frame’s centerplate and is held using 3M VHB tape. You mentioned IMU vibrations. What are they and where did you find that parameter?[/quote]
If you’re reading the dataflash logs this will get you started:
[quote]High vibrations cause the Copter’s accelerometer based altitude and horizontal position estimates to drift far off from reality which leads to problems with alt hold (normally rocketing into the sky) or Loiter (drifting).
Vibrations are best viewed by graphing the dataflash’s IMU message’s AccX, AccY and AccZ values. The AccX and AccY values (primarily used for horizontal position control) should be between -3 and +3 m/s/s and the AccZ should be between -15 and -5 m/s/s. The accelerometer values will change momentarily as the copter moves up and down which is why it is better to pull the data from a portion of the flight where the copter was mostly stationary but even with a copter that is moving you can still see the vibration levels by comparing the difference between the top and bottom of the “grass”. an occasional blade of grass going over the lines is ok but if it’s sustained then it’s likely a real vibration problem.[/quote]