I'm a completely new quad pilot who just spun up the motors on his homemade quadcopter for the first time today and started stepping through the "First Flight" exercises from the ArduCopter Wiki. I was working on achieving a stabile hover a few feet off the ground as recommended in the Tips for your first flight section when, all of a sudden, my quad rose up and started to "fly away" with the throttle at zero. I'll admit, I panicked a bit because all I could see was my brand new expensive project flying away from me. After freaking out and not knowing what to do, I gave it a little throttle and it seemed to start to respond (though I don't really have the experience necessary at this time to know if this was real or just coincidence). Needless to say, I set the quad down as quickly as I could while still being gentle. After it was on the ground, I could not get it to stop the motors or disarm until I found the Arm/Disarm button in Mission Planner.
I've downloaded the log files from the APM and have been trying my best to analyze them, but I could really use some help. I know that the APM went into RTL mode (thankfully, I had followed my own checklist and verified my GPS fix before arming my quad) followed by a brief period of loiter mode, but I can't seem to figure out why. I have all six flight modes set to STABILIZE and can verify that my channel 5 data did not change (if you're looking at my log file to verify this, please see note #2 below). I have my failsafe threshold set to 975 and it looks like my channel 3 data did not drop below 1000.
I suspect you guys probably get this all the time, but if anyone is willing to help me analyze my log file, I would be eternally grateful. At this point, I'm still a little bit freaked out and nervous to try flying again until I understand what may have happened. Does anyone have any thoughts?
A couple of caveats about the attached log file:
- I had the quad powered up for quite some time while it sat on the kitchen counter indoors and I checked settings and configurations. This will show as zero data for the RC_CHANNELS_RAW data. I then took the quad outside and powered on the transmitter while a family member carried my laptop for me.
- I performed a radio calibration (at about 1880 on the x-axis) after getting the quad on the ground. Feel free to chastise me for this if it is a bad idea on a live aircraft...it's the only way I'll learn my lesson. At the time, I was concerned that my quad may have gone into failsafe mode and it was all I could think of.
Replies
Below is some pages that should help with your logs.
I assume you were only flying in stabilize mode only?
Logs
There are a few wiki pages where we talk about how to use the dataflash and tlogs here (http://code.google.com/p/arducopter/wiki/AC2_Datalogging), here (http://code.google.com/p/arducopter/wiki/AC2_Record) and here (http://code.google.com/p/arducopter/wiki/AC2_Logs). The last two pages have videos on them where I go through some of the details so that might be useful...
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