Hi all,

I am looking for a drone that will do a good job of shooting windsurfing on autopilot. Given the speed of the subject+ the wind, it needs to fly pretty fast. I see that the current P4P and P4A can do ActiveTrack at up to 50kph. Is this also true of the older P4? 50kph?

What happens if the drone can't keep up? For example, a gust of wind makes it fall behind - would it drop Activetrack altogether? Will it keep pushing through and try to catch up to the subject? If you have made it follow you at these speeds, are there any other considerations about quality/reliability?

I just don't want to spend 1200+ on the new generation of drones and thinking about getting a refurbished P4. But even that is a lot of money for something I am not sure will work so well (even 50kph seems borderline given that I can sail in winds of 40kph).

Thanks! Nikita.

P4 does 20mph while the P4P does 30mph with active track, so you are better off with the newer models, also importantly the newer ones can see a lot further so if they get left behind then there is a much better chance of them keeping a lock on the target while they catch up.

To some extent the wind doesn't matter, I have had my P4 keep track in a 43km/h wind.  However top speed into the wind was then only 3km/h - while doing an active track orbit it was barely moving on the upwind segment!   Take it out of active track and use sports mode and it can still get about in a 43km/h wind with decent video but it does start to get a bit difficult for the pilot since there is a huge difference in top speed depending on direction.

I don't really think it is feasible to pilot the drone while also wind surfing, you will need to lock onto the target once you are on the board with the sail up.  However active track will make it a lot easier for someone on the beach to produce a nice video.

Not sure how well they cope with the fact that a windsurfer changes shape significantly depending on direction?  I would expect fairly frequent lost targets but also some good video.

Theoretically, P4 can follow a subject up to 36km/h. If the subject is too fast to follow, the drone might lose the followed subject, then it will hover at that position until the subject comes back to the screen. But notice that the drone might crash if the wind is too strong to resist. So please kindly select a good place and good weather to fly.

Nigel_ Posted at 2017-9-28 04:16
P4 does 20mph while the P4P does 30mph with active track, so you are better off with the newer models, also importantly the newer ones can see a lot further so if they get left behind then there is a much better chance of them keeping a lock on the target while they catch up.

To some extent the wind doesn't matter, I have had my P4 keep track in a 43km/h wind.  However top speed into the wind was then only 3km/h - while doing an active track orbit it was barely moving on the upwind segment!   Take it out of active track and use sports mode and it can still get about in a 43km/h wind with decent video but it does start to get a bit difficult for the pilot since there is a huge difference in top speed depending on direction.

Ok, you say that P4 is limited to 36kph (20mph) in Track mode, but you had wind of 43 and it also managed to move a bit. So it must have had air speed of about 50kph? Do you have the newer P4 or the standard?

Too bad their P4 page with specs is gone. You can buy it (refurbished), but I can't find the official specs!!!

Thanks again!

nikitapiankov Posted at 2017-9-28 08:16
Ok, you say that P4 is limited to 36kph (20mph) in Track mode, but you had wind of 43 and it also managed to move a bit. So it must have had air speed of about 50kph? Do you have the newer P4 or the standard?

Too bad their P4 page with specs is gone. You can buy it (refurbished), but I can't find the official specs!!!

You can download the P4 manual still, it was updated not long ago, I guess you will find the specs in there.

Yes, I think max air speed of 46kph in active track, but only if it is windy, following a windsurfer max is presumably 36kph since the windsurfer is never going to sail straight into the wind!

76kph in sports mode even without wind, although I don't think I would want to be the pilot trying to film a windsurfer at that speed!
  
Mine is a standard P4, for most purposes perfectly adequate.

In wind over 40kph I would be a bit worried about it getting salt spray inside, very bad for electronic circuits.

I was trying to follow my boat in Active Track with my few months old P4 and I was disappointed. When the P4 couldn't keep up with my slower speed it gained altitude to keep me in the center of the screen. But even when I was drifting with 3-4Km\h the drone gained altitude.

Nigel_ Posted at 2017-9-28 09:19
You can download the P4 manual still, it was updated not long ago, I guess you will find the specs in there.

Yes, I think max air speed of 46kph in active track, but only if it is windy, following a windsurfer max is presumably 36kph since the windsurfer is never going to sail straight into the wind!

Just looked at the manual. It cites the max speed in S mode a bunch of times (20m/s), but doesn't say what it is for P mode! ANYONE???

nikitapiankov Posted at 2017-9-28 10:21
Just looked at the manual. It cites the max speed in S mode a bunch of times (20m/s), but doesn't say what it is for P mode! ANYONE???

P-mode with the forward sensor enabled, the speed reaches 10 m/s, 16 m/s with the forward sensor unable.

DJI Thor Posted at 2017-9-29 01:39
P-mode with the forward sensor enabled, the speed reaches 10 m/s, 16 m/s with the forward sensor unable.

Thank you, Thor. 16ms will probably be about enough for it being somewhat useful. There won't be any objects to hit over open water, so I am guessing the lack of forward sensor won't matter.

nikitapiankov Posted at 2017-9-29 07:47
Thank you, Thor. 16ms will probably be about enough for it being somewhat useful. There won't be any objects to hit over open water, so I am guessing the lack of forward sensor won't matter.

You are welcome, if you unable forward sensor, please flight carefully, watch out the flight environment coz it can not avoid the collision.