DroneFlying
Captain
Flight distance : 10774613 ft
United States
Offline
|
Phan-TOM Posted at 2017-7-19 17:22
Spent the day trying to figure this out. Several sessions with DJI support chat, four different support agents, multiple times refreshing firmware, calibrating IMU, compass, sticks on the controller and recalibrating the forward and downward facing sensors, and still no change. It flies straight for 10-20 feet, then dives for the ground, slides left or right several feet or climbs until I stop it. No telling which way it will go either. It just doesn't want to fly in a straight line. Numerous attempts to recalibrate everything and test fly have not helped.. and really, neither has an entire day working with DJI support.
I did look at your files a little a couple of days ago and was hoping to come up with something more conclusive, but at this point all I can say is that your concerns about your Mavic are justified, because it doesn't seem to be functioning normally. I was going to review the videos again this morning, but it looks like you took them down and to be honest I'm not sure I'd gain more insight anyway.
The drifting appears to have a couple of different causes. First, both the videos and DAT files indicate that there's a bit of yaw drift occurring even when your Mavic is stationary. I've seen a few other people mention this happening to them lately but unfortunately I'm not aware of there being a definitive cause or solution. I know you already mentioned that you've done IMU and compass calibrations, and the DAT file shows no stick input so I'd guess that calibrating the remote also won't help, though I suppose it couldn't hurt either.
The more dramatic lurches you're seeing in your driveway may be caused by the reduced GPS health that occurs due to the thick canopy of trees around your driveway. In other words, this may be the Mavic trying to adjust its position after it regains a GPS location that it can trust. The DAT file does show a number of brief drops in the GPS health and also a handful of GPS_POSITION_NONMATCH errors, though the correlation between them is far from perfect so I'm not at all certain this is really what's causing it. I did notice that at least in the early minutes of the railroad track videos -- where you were flying in a more open area -- that you appeared to only encounter the less dramatic yaw drifting and not the more serious sliding experienced in your driveway.
The VPS data, on the other hand, is a bit more clear-cut: unless there's something physically interfereing -- such as an obstructed sensor or some attachment that's interfering with the readings -- it definitely appears that the VPS readings are sporadically incorrect, and that's why you're seeing the sudden drops in altitude. In other words, the Mavic suddenly thinks that its altitude is higher than it really is and drops down to compensate.
So while the data related to not being able to fly straight is inconclusive, the bottom line is that there does appear to be a problem with your Mavic and it's probably one that should be covered under warranty. At least that's my personal opinion and hopefully DJI agrees. I'm sorry that I don't have a more definitive diagnosis for you, but I am pretty confident in saying that this is something you should continue to pursue with DJI, and I personally would be pretty insistent on getting a warranty replacement.
Good luck and let us know how things turn out. |
|