Jamming / interference?

[bnsr]

I was flying today, following the vehicle I was in - so the range was within a few hundred feet at all times, in a rural area. Everything was going great until the AC suddenly lost connection.

Running the data through Healthydrones, just about everything was going well (with the exception of some motor overloading) until the signal went catastrophically bad. I wrestled with it for a while to prevent an RTH - it wouldn't have made it across the lake, I don't think - and eventually it descended into a tree, tumbling about 100ft to the ground and damaging the gimbal.

My question is - what might cause such a marked signal degradation in an area like this?

Extra points - the quicktime file is damaged. Any tips on how to recover?

 

[BigAl07]

Often times if you power ON the aircraft with the SD card in it and do a normal power OFF it will finish writing the data to the SD card. Due to gimbal and possible other damage that's probably not going to help you.

Try this link (be sure to use the latest version of the software)
App to fix corrupted Video Files (new one)

 

[Meta4]

I was flying today, following the vehicle I was in - so the range was within a few hundred feet at all times, in a rural area. Everything was going great until the AC suddenly lost connection.

My question is - what might cause such a marked signal degradation in an area like this?

It's unlikely that there was any interference and much more likely that you just had poor signal.
There are plenty of spots after 50% where your flight data shows poor signal.
Possible obvious causes might be trees between your controller and the Phantom, the car roof blocking signal or controller not pointed toward the Phantom.

There are a couple of preventable problems with your flight that could have caused you more problems.
You left the home point back over a mile away across the lake which could have caused issues if the Phantom tried to RTH and also would have had the Phantom wanting to go back when it calculated battery level getting low to make that trip.
At any time you could have reset the homepoint to either the Phantom's location or the controller's and prevented RTH being a big issue.
You flew right through to 6% which is way past safe. You should have reeled it in before you got down to 20%.

 

[bnsr]

It's unlikely that there was any interference and much more likely that you just had poor signal.
There are plenty of spots after 50% where your flight data shows poor signal.
Possible obvious causes might be trees between your controller and the Phantom, the car roof blocking signal or controller not pointed toward the Phantom.

There are a couple of preventable problems with your flight that could have caused you more problems.
You left the home point back over a mile away across the lake which could have caused issues if the Phantom tried to RTH and also would have had the Phantom wanting to go back when it calculated battery level getting low to make that trip.
At any time you could have reset the homepoint to either the Phantom's location or the controller's and prevented RTH being a big issue.
You flew right through to 6% which is way past safe. You should have reeled it in before you got down to 20%.

Thanks, understood. Unfortunately I lost connection well before 6% - I would say around 2/3 through the flight. After that I was wrestling with it through intermittent signal trying to prevent an RTH. You are quite correct however that I could have reset the home point - in the moment I forgot how to do so.

Where you see the poor signal - that's where it turned the corner from flying well to uncontrollable. None of my variables changed during that time - distance from the AC, direction of the controller, orientation inside the vehicle. My point is that it went from 5/25 minor signal errors to 100/500 MSEs without any difference in my situation. Even after I exited the vehicle and started walking back toward the AC's position (while it was still airborne) it didn't recover signal in any meaningful way. Hence my question about external factors.

What I can say about this location is that cell service drops off pretty badly where I lost the AC - but that shouldn't have any effect on the connection between the controller and the AC, correct?

 

[sar104]

Thanks, understood. Unfortunately I lost connection well before 6% - I would say around 2/3 through the flight. After that I was wrestling with it through intermittent signal trying to prevent an RTH. You are quite correct however that I could have reset the home point - in the moment I forgot how to do so.

Where you see the poor signal - that's where it turned the corner from flying well to uncontrollable. None of my variables changed during that time - distance from the AC, direction of the controller, orientation inside the vehicle. My point is that it went from 5/25 minor signal errors to 100/500 MSEs without any difference in my situation. Even after I exited the vehicle and started walking back toward the AC's position (while it was still airborne) it didn't recover signal in any meaningful way. Hence my question about external factors.

What I can say about this location is that cell service drops off pretty badly where I lost the AC - but that shouldn't have any effect on the connection between the controller and the AC, correct?

The signal loss doesn't seem to be readily explained by the location. If you can borrow one (assuming that you don't have one), I'd go back there with a spectrum analyzer and check the 2.4 and 5.8 GHz bands.

 

[bnsr]

Often times if you power ON the aircraft with the SD card in it and do a normal power OFF it will finish writing the data to the SD card. Due to gimbal and possible other damage that's probably not going to help you.

Try this link (be sure to use the latest version of the software)
App to fix corrupted Video Files (new one)

Thanks Al, that worked like a charm (even after the Grau tool failed).

Here's the video of the whole thing; the 5 minutes of wrestling with it after connection was lost is sped up:
Dropbox - Sequence 1.mov

 

[bnsr]

The signal loss doesn't seem to be readily explained by the location. If you can borrow one (assuming that you don't have one), I'd go back there with a spectrum analyzer and check the 2.4 and 5.8 GHz bands.

Interesting - will do that, good plan.

 

[kerrylaw7307]

How did you get these shots? Did you have a driver and you were hanging out the window? I liked what I saw until the end! LOL

 

[bnsr]

Thanks! My buddy was driving, and I was riding in the passenger seat. I tried originally to use the 'follow me' mode, but it doesn't account for altitude changes - and it didn't work at all.

This method of having someone else drive at around 30mph worked great until the one spot where I lost all signal. Good news is that the UAV received only minor damage - the gimbal appears to be fine after reconnecting the cables. Just waiting on some $8 hardware to reattach it to the airframe and see if it works again.

How to do it the expensive way:

 

[HWCM]

It looks like it went into auto land.