RANGE AND ENDURANCE TESTING
Hello.
Right this morning was cold and a bit windy, and I forgot my gloves and the SD card for the camera (what can I say, it was a very early start). BUT the purpose of the flights was always going to be range and endurance testing with the gimbal, so I have re-attached my Flytrex (it does fit under the aircraft with the gimbal properly installed, although I needed to use double-sided tape as opposed to the 3M Command picture hanging strips due to their thickness).
I'll summarise the conditions and link to the Flytrex data for the two flights:
FLIGHT ONE
http://www.flytrex.com/mission/quadcopt ... ton-20368/
Winds 10-12mph, gusting 18
Temp +4.5C
Flight location: Open farmland, no other wifi in range, take-off point on higher ground than that overflown. No obstacles, trees, etc.
Flight type: low energy, typical photographic/video flight profile including periods of hovering, not much full stick deflection
Battery percentage Motors start: 99% Motors off: 21%
Run time 17m10s
Note: I have a modded antenna set-up (ground end only) so these observations are made relative to range performance with those mods but without the gimbal.
* No loss of wifi signal at the maximum range - camera was facing directly away in relation to control position - some mild skipping of frames were noted.
* Towards the end of the flight I did a run out to 800ft+ with gimbal motor side of camera directly facing my control position. No loss or degradation of wifi signal was observed.
* Below 30% battery I got occasional temporary battery low alerts if suddenly pushing hard on the sticks - the consequent voltage drop with the gimbal attached seems to be enough to trigger this when sub 30%. However easing back on the sticks will stop the alert and prevent any autoland kicking in.
FLIGHT TWO
http://www.flytrex.com/mission/quadcopt ... ton-20371/
An impromptu flight with Shedracer (nice to meet you!), lower altitude and the sun had come out so condition slightly warmer and less windy than previous flight. Flight type was more "sport flying" with higher average speeds and plenty of turns and maneouvres. I brought the aircraft in close a little early and used the opportunity to run the battery right down for calibration as per DJI manual.
Flight location: Large open field, no obstacles, controlling and flying in close proximity to another Vision.
Battery percentage motors start 99%, motors off <5%
Run time 18m26s
* No issues noted when flying with another Vision (which was stock in terms of antennas).
* Less manoeuvring earlier could probably have pushed this over 19 minutes, although fighting autoland all the time of course.
MY CONCLUSIONS
1. In my setup I didn't notice any degradation of wifi performance at all (in fact in flight one above I achieved a personal record for distance, and was only limited by the control signal running out of grunt). I also tested the worst case scenario (gimbal motor facing the transmitter) and had perfectly clear wifi rolling out to 800ft+ (this was not a limit that I hit, I just needed to come on back in). I am running a stock Vision aircraft with a Horizon FPV Antennas 9dBi Blackhawk Micro (LHCP) 2.4GHz directional helical antenna on the range extender (and a Horizon FPV Antennas 9dBi Blackhawk Micro (LHCP) 5.8GHz on the transmitter). I can't tell you how you will be affected if you are running totally stock, but unless you want to do hardcore FPV it looks like simple ground-end only antenna mod on the range extender can, from my results, completely negate any issues the gimbal motor may cause.
2. Endurance tested on a "normal" flight profile (normal for me, at any rate) was solidly 17 minutes without taxing the battery at all. If I had pushed down to the autoland threshold at 15% then flight one could probably easily have pushed to 18 minutes or more. Flight two was more "sporting" and would probably have come in nearer to 16 minutes if I had not wanted to let the battery run all the way down for recalibration purposes.
Hope this data is useful for those who've asked for it. It's only from 2 flights, of course, but I'll continue to post all my logs to my Flytrex account and monitor the averages. But so far, so good.
