DJI Air 3 - Waypoint Mission Crash into sea

[PeRo]

Thanks @JNB!

DJ Wes: "Because the last two waypoints were so much higher, the flight path went below the height of waypoint 2 as it approached waypoint 2 in order to make a smooth curve up to the last two higher waypoints."

So that means that there is proof of the idea from @DJ Wes that the WP algorithm allows to fall below the pre-programmed minimum flight altitude in case of certain curve interpolations?

No hint, no warning?

Weird!

 

[DJ Wes]

So that means that their is proof of the idea from @DJ Wes that the WP algorithm allows to fall below the pre-programmed minimum flight altitude in case of certain curve interpolations?

No hint, no warning?

The type of curve that DJI Fly uses for waypoint missions goes through the control points (waypoints). An obvious result of this is that this type of curve (spline) cannot satisfy the "convex hull" property. Most waypoint flights are configured and occur in the X-Y plane where the flight path can easily be seen on the screen where it is displayed. The flight path will often be seen extending beyond the limits of a polygon defined by the waypoints. Since the flight path is created in 3D space, this extension will occur both laterally and vertically. This is simply the nature of a spline that goes through its control points.

If you are interested, I have more information on this here:

Litchi Missions vs DJI Fly Missions

Wes Barris

www.litchiutilities.com

 

[JNB]

Thanks @JNB!

DJ Wes: "Because the last two waypoints were so much higher, the flight path went below the height of waypoint 2 as it approached waypoint 2 in order to make a smooth curve up to the last two higher waypoints."

So that means that there is proof of the idea from @DJ Wes that the WP algorithm allows to fall below the pre-programmed minimum flight altitude in case of certain curve interpolations?

No hint, no warning?

Weird!

Yes, it may fall below the waypoint heights - DJI directed me to RTFM (page 41) :

 

[JNB]

The type of curve that DJI Fly uses for waypoint missions goes through the control points (waypoints). An obvious result of this is that this type of curve (spline) cannot satisfy the "convex hull" property. Most waypoint flights are configured and occur in the X-Y plane where the flight path can easily be seen on the screen where it is displayed. The flight path will often be seen extending beyond the limits of a polygon defined by the waypoints. Since the flight path is created in 3D space, this extension will occur both laterally and vertically. This is simply the nature of a spline that goes through its control points.

If you are interested, I have more information on this here:

Litchi Missions vs DJI Fly Missions

Wes Barris

www.litchiutilities.com

This makes sense - I can see the reasoning behind it - it's better for cinematic, smooth footage, worse for crashes into the sea LOL

 

[PeRo]

Yes, it may fall below the waypoint heights - DJI directed me to RTFM (page 41) :

View attachment 173179

Special thanks! Was not aware of this hint in the Manual.