Looking at the FULL log file you indeed did not touch the throttle except for a few minor blips here and there from 66.5 seconds in all the way to 131.8 seconds yet in that time your altitude goes from 48.5 meters to over 70. You also have a compass error toward the end, maybe after it already landed on your roof. At 132.5 seconds you give it full throttle but it's still on it's way down.
Phantom 4 fell out of the sky...why?
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I've read on here that the last seconds of video doesn't always get written to the card in a crash but may still might be in the bird. Turning it back on and recording a few seconds sometimes pushes it to the sd card.
Crash looks weird, following and doesn't look like you did anything wrong.
GPS satellite count was always good, mostly between 17 and 19 but as low as 14 toward the end. Also you were in P flight mode the entire time, and likewise it also shows your Phantom never went into attitude mode, always GPS mode.
How about if I host a zipped file on my server?
Here is the zipped .dat file http://www.tokenradio.net/Aviation/FLY036.zip
T!
When I first got my Phantom and turned to this site, every 10th thread was about a crash blamed on flying a partially charged battery. Most of those usually saw a battery warning and a voltage drop just before falling and it doesn't seem to be your issue but O have made a point to fly on fully charged batteries.
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I would do 2 things....
1) inform DJI of everything including any footage you have left
2) include the pics of the damage it caused to the truck.
In theory it sounds like a malfunction and not human error. With the damage it caused you, I would expect a brand new replacement with extra batteries thrown in to make up for the damage to the truck
Neon Euc
1) inform DJI of everything including any footage you have left
2) include the pics of the damage it caused to the truck.
In theory it sounds like a malfunction and not human error. With the damage it caused you, I would expect a brand new replacement with extra batteries thrown in to make up for the damage to the truck
Neon Euc
The truck (actually a 1999 ZR2 Blazer) is 18 years old with 200k miles on it and shot paint, it is my desert off-road beater, very dependable but not really pretty, bordering on ugly. Believe me, I don't care about a couple dents in the roof.
What I do care about is if I did something wrong I would like to make sure I do not do it again. If I did nothing wrong and it is a failure of some kind I want to take care of the failure so it does not happen again. If it is an external cause, such as GPS jamming / testing or some other RFI / EMI issue I would like to identify it so that I can take measures and it will not happen again.
T!
Ok so after digging into your logs, It does appear as though the craft developed a mind of its own for one reason or another in terms of the altitude. The barometer height and GPS height seemed to skew around the 100 second mark. It also seems as though the drone realized this as this was in the log:
106.061 : 846153654 : 9009 [L-FDI][FDI][CTRL]: fault on , height_ctrl_fail
As for the yaw, the yaw appears to have been commanded correctly by you with your stick. The yaw from your RC is the green line on the 2nd graph, and you can see it matches the yaw direction that occurred in the first graph which is the craft yaw (also green).
That said, there was definitely some kind of issue that occurred with the barometer and height control of the craft. I don't know if it was caused by the environment or hardware. You could either send it back to DJI for diagnostic/warranty, or you could wait and see if it happens again.
106.061 : 846153654 : 9009 [L-FDI][FDI][CTRL]: fault on , height_ctrl_fail
As for the yaw, the yaw appears to have been commanded correctly by you with your stick. The yaw from your RC is the green line on the 2nd graph, and you can see it matches the yaw direction that occurred in the first graph which is the craft yaw (also green).
That said, there was definitely some kind of issue that occurred with the barometer and height control of the craft. I don't know if it was caused by the environment or hardware. You could either send it back to DJI for diagnostic/warranty, or you could wait and see if it happens again.
I'd be glad to. I'm just still such a noob here that I'm having surprising difficulty finding a way to do so.
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Well then, given that the dents actually increase the cachet of the vehicle, giving it more charm.
Thanks for looking at those for me.
I plotted the data that was in the csv file that resulted on the phantomhelp page and came up with plots similar, but less detail, to what you got. Of course I can’t see the gpsAlt or one of the two Yaws in that file.
After seeing the GPS alt data to me it looks like at some point the recorded baroAlt started lagging the real world badly. The Barometric alt data should respond as fast or faster than the GPS alt data, and does so until after the 77 second mark. But from that time on the GPS alt data seems to be responding before the baro alt data, with the same general trends after about 110 seconds or so but with several seconds of time delta.
Note that the GPS alt data ends at about the right altitude on top of the truck, while the baro alt data is still coming down at that point (when I turned the P4 off), with a 35+ meter delta between the two.
To me it really looks like the system was responding to baro data that was not keeping up with the pace of the real world. Probably after the height_ctrl_fail all bets were off on its ability to keep itself up in the air with no elevation inputs from me. If I had been looking at the thing instead of head down I probably would have been able to control it to the ground.
I can’t think of any way a failed barometric sensor could cause this kind of lag. Errors yes, no input yes, but several seconds lagging input seems more of a processing system error than a barometric sensor error. At least to me, but what do I know, I am an RF guy, not a software guy
What really concerns me, I mean besides it happened at all, is that the obstacle avoidance with its Vision Positioning sensors, with the ultrasonic altitude detection, apparently never attempted to slow the fall of the aircraft, and I was in P mode according to the data.
I don’t remember me commanding the start of the yaw, in fact I thought I responded trying to counter the yaw, however the RcRudder vs Yaw seems to support that yaw was under control until impact.
At this point I will watch the thing closely for the next few hops. If it shows any future issue with alt control I will contact DJI, but until it shows an issue again I will treat this as an isolated glitch. The next two flights after that were essentially flawless.
I am somewhat surprised and pseudo pleased that the P4 wacked the truck hard enough to dent the roof, and made a heck of a thump sound, with the only detectable damage on the P4 as a broken prop that probably impacted an antenna just before smack down.
By the way, is there any data out there on the format of the .DAT file or maybe does a converter exist? I would love to be able to look in detail at the information in there.
Thanks,
T!
Sure you can get everything I looked at using DATCON and CSVVIEW: CsvView/DatCon
