I tried the mapping today, constant altitude, with a Mavic Pro. It worked until WP 7, when it stopped for many seconds, then again at WP 9, longer, and finally at WP 11 until the mission was automatically aborted due to time overrun.
Read this topic:
Details for debugging:
I ran the mission twice and it behaved the same both times. The problem occurred the 3rd time it was to turn after a photo leg. The drone stopped just before the turn. There was a high wind warning although there was no wind. The times when it eventually did continue, it snapped the photo, turned left, and flew on.
My guess: The drone stopped because it had reached the WP, but the app was still waiting for it to arrive. The app interpreted the “delay” as caused by high wind. The discrepancy in location might be due to a conversion error in the coordinate system. One possible fix would be to overshoot the WP a bit (and take the photo in flight, as with the others), and or to have a “snap” margin to account for these small errors in position. Depending, of course, on what the error is and how the code is written.
Hi, had already read it, and it has nothing to do with the bug I found.
I think it’s caused by a false object detection by the forward facing object avoidance sensors caused by sun rays.
This is a well known problem (I experienced myself several times), especially when the sun is low and in front of the drone.
Try disabling object avoidance.
Would you define “constant altitude”? Does that mean a constant height above take-off or a constant height above ground? The two will cause a difference in how photos are captured at interior photo locations (if that is where your drone is stopping).
Do you use AirData to analyze your flight logs? The data will verify whether or not there was sufficient wind at the height you were flying to cause that warning. Wind speed is almost always greater the higher the drone is. The warning is a result of the pitch or roll angle of the drone approaching its maximum allowable value in order to maintain its GPS location.
There would be no conversion errors. Your Mavic Pro is a very capable drone. The mission was loaded into the drone and executed natively by the drone. The app is not even required to be running during a waypoint mission on a Mavic Pro.
Waypoint missions where the drone has difficulty reaching a programmed waypoint are normally only seen in VSC (virtual stick) drones. The Mavic Pro has native waypoints and would normally not experience this type of error.
The camera was facing straight down and it was overcast.
Altitude as in Latitude, Longitude, Altitude. The wind was less than 2 meters per second, i.e. calm.
That does not answer my question. If you chose height above takeoff no interior waypoints would have been generated. If you chose height above ground, interior waypoints may have been generated depending on the terrain. If the drone never stopped in the interior of the mission, it doesn’t matter.
It may not have been windy at ground level but depending on how high you flew, it could have been windy at altitude. The flight logs will show this.
The drone was very close to me, I saw it, there was no wind. As a geographer I can affirm that constant altitude is related to the geoid, not to ground.
SOLVED:
Today I flew several tests and either of two changes resolved the issue:
- Turn in curves instead of 90° angles
- Fly much slower
In 6 m/s and 90° turns it stopped abruptly, no slow-down but full brakes, and that triggered the OBSTACLE alarm. I suppose the camera swang so wildly that it got detected. When flying in 3 m/s it worked fine, and also when doing curves instead.
Thanks to all who gave input.
The logs would confirm that. If there was no wind at the height of drone, yet it issued that high-wind warning. There could be a problem with the drone.
DJI drones estimate height based on real-time barometric pressure as compared to that when the drone took off. As a result, the height is always relative to take-off location. If the “Above Ground” option is used, elevation data is used to adjust the height according to the ground elevation under each waypoint. However, this calculation assumes that the ground elevation under waypoint #1 is the same as the ground at the take-off location. Also, if the “Above Ground” option is used, the barometric height may have to be adjusted by placing extra waypoints along the flight path causing more stops (with straight line missions). You mention “geoid”. If you are referring to the ellipsoidal approximation of the earth’s surface used in GPS height, that has nothing to do with waypoint height of a DJI drone.