Multi Battery Flights

Equipment:

Drone: DJI Phantom 3 Pro, firmware version 1.8.80; RC firmware version 1.6.0
Map Pilot App: v1.5.1
Ipad mini 2: iOS 9.3.2

All other Apps closed; i.e. nothing running in the background

Flight altitude: 120 - 150m with bright sun.

Issues:

When using auto exposure, the drone only flies at approximately 4.4 m/sec. Max flight speed is set much higher, and the setting "Slow aircraft according to light conditions" is turned off.
Using manual exposure, the first flight is great and drone flies at the desired ~7.4 m/sec. After powering down to replace the battery 1 of 2 things happens: a) the drone returns to abandonment point but will only fly very slowly (4.4 /sec) regardless of the amount of available light; or b) drone begins taking pictures the minute it hits the cruising altitude and returns to the abandonment point (at 4.4 m/sec) taking pictures the entire way.

The only way to fix is to create a brand new mission and resume flying. All's great for first flight then same problems begin again. Any thoughts?

Cdamon June 07, 2016 19:31

Official comment

1. If the Slow Aircraft setting was turned off it wasn't light related. What was your overlap setting? What is the SD card speed setting? If the overlap was high and your SD card speed was slow that will limit your maximum allowable aircraft speed to make sure that the framing limits mesh with the overlap requirements.

2. The aircraft should fly the same speed for all flights in the mission. If it flies 4.4 m/s in the first it will do the same in all subsequent flights. We will look into this because we have heard some other issues related to multi battery missions and the manual exposure setting. Are you manually landing or allowing it to land on its own? Sometimes there are some extra modes thrown by the DJI software and this will drop extra Abandonment Points which will cause the behavior you are seeing. If you let the aircraft come all the way back under automated control and just take over when it is time to land this will not likely happen.

Please email any pertinent log files to mapping@dronesmadeeasy.com so we can inspect them to see what might have cause the issues.

Thanks for the detailed reports. We hope to fix these issues in the next release.

Jay June 08, 2016 21:19

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2 comments

Thank you for responding.

After an additional 7 flights today, we seemed to have narrowed the issues down to using cached or offline mission plans. If we design a mission and use directly, the system operates as expected -- flight speed is consistent between multiple flights (on multi-battery missions); Auto exposure doesn't excessively limit drone speed; and the drone returns to the abandonment point before image capture begins again.

We always manually land the drone once it begins its decent. If manual control is triggered before the drone actually begins to decend, a new abandonment point is added and that's where the drone returns to when resuming the next flight. Even following this method, when flying a cached mission, the 2nd, 3rd, 4th, etc flights will only fly at ~4m/sec.

The SD card speed is set to 2.5 seconds and overlap is at 80%. These settings work perfectly fine when the system is operating properly and the images look great.

We have another 5 flights planned for Friday, so I will be able to confirm if direct planning and flying a mission mitigates/eliminates the gremlins. I will email separately a screenshot of the cached mission we were using, and the log files from the first 2 flights showing the drop in drone speed after the first battery swap.

Cdamon June 09, 2016 06:39 0 votes