Servers by jDrones

Everything was fine until this last flight


(Mike Gauthier) #1

My copter with PIXHAWK was working great after finishing autotune for all 3 axis. I flew it several times with no problem. Today, I took off as normal in Alt Hold mode and it was very jittery and was erratic with the altitude too. I tried to land it but it came down rather suddenly and just flipped over.

I will attach the log to see if someone can help me understand what suddenly went wrong. MissionPlanner.log (500.1 KB)

(Mike Boland) #2

I found your log was truncated with too many errors so I couldn’t have a look.

Is that the flight log, .bin file, from the flight controller?

(Mike Gauthier) #3

Yes, I downloaded the .log file using Mission Planner. I don’t know how to download the .bin file.

(Mike Gauthier) #4

Here is a fresh download of the log file.00000008.log (688.4 KB)

(Benjamin Mathon) #5

From what I can see your throttle input value was very high and your baro and ground speed values show that it was a nearly static flight.

So you are running on 3s, with a massive voltage drop under load, nearly a volt.

Was it a brand new battery?

(Mike Boland) #6

From a quick look,
Your problem seems to be not enough power and/or being unbalanced.

Your throttle is pegged to the max but the copter is reluctantly climbing with motors 3 and 4 being pulsed to minimum for most of the flight.

Were you fighting a breeze?

As @bendead noted your battery is barely keeping up with such a large voltage drop and you haven’t set up current measuring so I can’t tell you any more there.

For further help you really need to give us more detail about your setup and the flight in question.

(Mike Gauthier) #7

You both hit the nail on the head. It was a 3s battery with a weak cell. I installed a new fully charged battery and it flies great again.

Thank you so much for the help.