TLDR; Running Go4. Lost connection momentarily and RTH initiates. Thereafter the AC would not take ANY commands - from app (command timeouts) or RC. Returned to home but stopped landing at about 9+ ft due to “unsafe landing area.” Had to wait for batt to get to basically zero before it came down low enough to catch. Whew.
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The whole story plus logs...
Flew my P4P out from a lake shore out over the (frozen) lake and turned to come back when battery was about 60% (a minute or two before that I got a warning that it was returning to home due to low batt. I was heading out on a headwind. So coming back would be a tailwind and I knew I’d have plenty of batt to get back. I was right).
On the way back it lost connection momentarily. Not sure if I ever lost downlink. Connection came back but it was R’ingTH. I wanted to take control back so I hit the X in Go4 to cancel RTH so I could continue to fly back manually. I got a “Command Timeout.” I kept trying multiple times with command timeout every time. Video and telemetry were fine. I tried to use the sticks to speed up or drop altitude - no response. I tried to cancel RTH with the button on the controller. It stopped beeping for about 5 seconds, then started beeping again. RTH continued. So I let it come back. (I hacked the RTH speed to be faster than stock so I was feeling that would help.)
My concern was what would happen when it came back and did autoland. I wasn’t in an open field. I was on the edge of a lake with benches and a road. And some grass. Could I take control and land it myself?
No.
It got overhead at about 350 ft or whatever alt it was flying at last I had control and started autoland. It was coming down in an OK spot. Not over the bench I launched from but a few feet away over some grass. I still wanted to catch it if I could because some rock sticking out of the ground a foot away. But I had no control.
It got to about 9 ft (eyeball estimate) off the ground and stopped - warning that it was an unsafe area to land. And it wouldn’t land. And I couldn’t force it to. I figured I’d wait for critical battery to force a land and I’d catch it because the ground below wasn’t perfect. edit: obstacle avoidance was off. There may be a setting to disable the safe landing. I’ll have to check and memorize that.
I waited for it to hover from about 25% battery all the way down below 10%. Then 5%. I got warnings saying it was landing due to critical battery.
It wasn’t landing.
It continued to hover. I killed the app and restarted. I restarted the RC. It reconnected fine as far as downlink. But still no control.
Continued to hover. So I figured it would hover till the battery died and shut the motors off. Didn’t think it would completely survive a 9+ ft fall so I waited to catch it in free fall.
Much to my relief it start a slow descent at 1% batt or less. So I gently caught it by the landing gear and it shut off.
The drone had a mind of its own. I’m just glad it was a sane mind. But now I need to figure out what happened.
Any ideas would be appreciated. I’m charging the battery now to see if the problem persists.
Here is the airdata link of the main flight (there is a separate one for the landing but I doubt it’s interesting):
Airdata UAV - Flight Data Analysis for Drones
Here is the phantomhelp upload of the main flight from Go4:
DJI Flight Log Viewer - PhantomHelp.com
I’ll post more info from the power up when that happens.
.....
The whole story plus logs...
Flew my P4P out from a lake shore out over the (frozen) lake and turned to come back when battery was about 60% (a minute or two before that I got a warning that it was returning to home due to low batt. I was heading out on a headwind. So coming back would be a tailwind and I knew I’d have plenty of batt to get back. I was right).
On the way back it lost connection momentarily. Not sure if I ever lost downlink. Connection came back but it was R’ingTH. I wanted to take control back so I hit the X in Go4 to cancel RTH so I could continue to fly back manually. I got a “Command Timeout.” I kept trying multiple times with command timeout every time. Video and telemetry were fine. I tried to use the sticks to speed up or drop altitude - no response. I tried to cancel RTH with the button on the controller. It stopped beeping for about 5 seconds, then started beeping again. RTH continued. So I let it come back. (I hacked the RTH speed to be faster than stock so I was feeling that would help.)
My concern was what would happen when it came back and did autoland. I wasn’t in an open field. I was on the edge of a lake with benches and a road. And some grass. Could I take control and land it myself?
No.
It got overhead at about 350 ft or whatever alt it was flying at last I had control and started autoland. It was coming down in an OK spot. Not over the bench I launched from but a few feet away over some grass. I still wanted to catch it if I could because some rock sticking out of the ground a foot away. But I had no control.
It got to about 9 ft (eyeball estimate) off the ground and stopped - warning that it was an unsafe area to land. And it wouldn’t land. And I couldn’t force it to. I figured I’d wait for critical battery to force a land and I’d catch it because the ground below wasn’t perfect. edit: obstacle avoidance was off. There may be a setting to disable the safe landing. I’ll have to check and memorize that.
I waited for it to hover from about 25% battery all the way down below 10%. Then 5%. I got warnings saying it was landing due to critical battery.
It wasn’t landing.
It continued to hover. I killed the app and restarted. I restarted the RC. It reconnected fine as far as downlink. But still no control.
Continued to hover. So I figured it would hover till the battery died and shut the motors off. Didn’t think it would completely survive a 9+ ft fall so I waited to catch it in free fall.
Much to my relief it start a slow descent at 1% batt or less. So I gently caught it by the landing gear and it shut off.
The drone had a mind of its own. I’m just glad it was a sane mind. But now I need to figure out what happened.
Any ideas would be appreciated. I’m charging the battery now to see if the problem persists.
Here is the airdata link of the main flight (there is a separate one for the landing but I doubt it’s interesting):
Airdata UAV - Flight Data Analysis for Drones
Here is the phantomhelp upload of the main flight from Go4:
DJI Flight Log Viewer - PhantomHelp.com
I’ll post more info from the power up when that happens.
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