Same Litchi mission ran twice, once in the summer, once in the winter

[Steve_in_DE]

Here is the same Litchi mission ran twice with my Phantom 3 Advanced - once in the summer, once in the winter. They are autonomous flights with the heading and gimbal tracking POIs. The mission was laid out in google earth and then POIs, etc, added in the Hub. I synced them up reasonably well - note that I did NOT adjust the speed on either video here.

The only difference between the two is that the winter trip flew roughly 30 feet lower than the summer trip. I am not sure why that is - I am not clear on how the temperature affects how the Phantom determines it's altitude. Any ideas on that?

 

[GMack]

Don't know why the altitude changes, but these things are still a bit on the toy side, imho, and not some military-grade stuff.

I had my P4 do a high-speed three rotation in orbit mode with Autopilot once. With each rotation, the altitude dropped maybe 10 feet. Sort of a downward orbiting spiral until it was at eye level from maybe 30-40 feet up to begin with. Odd stuff, but my altitude often shows it flying at -40 feet too from take-off at zero feet. Same has happened on outward legs where the inbound leg will fly lower, but going out again on origional leg it goes back to same height as first run.

Dunno. Chinese quality components perhaps, or some electronics thermal drift.

 

[RodPad]

@Steve_in_NJ,
"the winter trip flew roughly 30 feet lower than the summer trip. I am not sure why that is - I am not clear on how the temperature affects how the Phantom determines it's altitude."

My Thought.

If you started your Phantom in the exact same place, then your starting elevation via the Barometer would be zero.

If cold air is denser than warm air?
Since the Barometer is deciding the elevation through the entire mission, wouldn't that effect its calculations?

More elevation plus or minus from zero would very its accuracy by some kind of percentage.

Rod

 

[Nightwolf]

Since the Barometer is deciding the elevation through the entire mission, wouldn't that effect its calculations?

Nailed it

 

[bsartist]

I did something similar. Ran the mission through all the seasons and instead of split screen, I cross faded from one season to the next.

 

[Phantom Phanatic]

Very nice. There is a noticeable difference in color and clarity between the two. Did you use a filter with the winter one and not the summer one?

 

[randaljds]

Bloody good stuff bloke!