I need to lower the maximum developed kinetic energy in P3 from 163 joule to 150 j

Ether the weight or the max speed or a combo.

Only speed from 16 to 15,2 m/s

Only weight from 1280 to 1171 g

Weight: to reduce the weight with 109 g (~9%) may be done some way but I expect that to be complicated as there would surprise me if not every thing unnecessary already has been removed.

Speed: the 16 m/s is specified to the ATTI mode, that suggest it is lower in other modes. As the P3 will, by it self, go in to ATTI mode I cant see how to lower the speed by forcing P-GPS mode

Another way may be to convince the programmers to include a 'low speed mode' that I can lock in to. This may also satisfy the authorities.

Those 13 j causes:

UAS 1B instead av UAS 1A permission

-slightly higher insurance, not a problem

-limited flight hight to 125 m (400 ft), not really a problem

-safety area around the P3 of a radius of 50 meters! Really annoying; people, cars, houses, and all not related to the flying has to be removed...

Any thoughts or suggestions? /BKE

WoW, after I got my magnifying glass out to read this I agree, would be good f there was an option that just limited the speed of the Phantom. Would make some situations easier to film in.

Agreed.   I would like to be able to lock the speed.   For an amateur like me, this would help from getting carried away with speed, etc.   Things would go a lot smoother creatively.   And, help you with the aircraft classification.

Hi ad6..

I don't have any suggestions on reducing the energy level, but curious..

Is this a legal requirement for you in Sweeden?

Cheers, Chris H.

kiwichrish Posted at 2015-6-11 14:46
Hi ad6..

I don't have any suggestions on reducing the energy level, but curious..

Yes, it a Swedish government limitation. And it forces the P3 in to 'class 2' of aircrafts that have this 50 meters safety radius, that makes it (almost) useless for real estate photo.

For commercial use in Sweden I need a pilot license for the specific unit, an insurance and every photo has to be sent (by snail mail) to the Swedish Armed Forces to get a clearance in advance. And this even for the smalest thinkable aircraft.

But if I use it non-comersial there is no limit, go figure...

OK, some more thoughts:

Reviewing the form again makes me believe that even if I reduce the weight (I had a idea of removing the camera) would do noting to solve the problem as it state 'maximum weight', and that would then _include_ the camera or _any_ payload to the maximum (DJI specified) limit.

Back to the speed then:

I got some (prompt) feedback from suport telling me that that in upcoming Ground station it will be possible to set the speed in each waypoint. I am not sure that will be the solution (to the authorities). And it is also uncertain when this will be possible.

So I am playing with two alterations. One is to aerodynamically change the drag by some light weight wings that will slow the P3 down the 0.8 m/s. Ugly but possible. It may be enough just to cover the landing gear in three sides (of the cube shape).

Another one it to reduce the Ø of the propellers, of course that will also shorten the flight time, I can handle that. Depending if on a (commercial) job or not the choise of altered or unaltered propellers is easy. I believe I can take little chunk of at a time off and measure the maximum speed and find when I get down to 15,2.

By the way, have anyone taken the P3 to a reality check? What is the real weight and what is the real maximum speed? Unfortunately I have mine stationed miles away out in the archipelago for the moment (for training, leraning and fun) and will not have access for some weeks. And the two critical parameters (to calculate the joule) is taken from DJI specification that may be a bit off.

/BKE

Any news on possible reduction on kinetic energy to 150J so we can have P3 in UAS 1A class (Sweden)?
Or documentation that the aircraft only produce 150J in GPS mode?

Thanks in advance!

How about propeller size?

Propeller or software restriction is ok but need some official documentation from DJI on that so it could be sent to authority in Sweden.

Done some preliminary tests, a standard duct tape covering back and sides (just one row in height) gives some good result. The test is not final as I want to do the air brake of Kapa and some 3D print locks and I also had a wind of 2-3 m/s (as can be seen in the graph going back and forth with or agains the wind).

Next test will be final and then comes the real test, convincing the authorities that this is enough to get a 1A permission... The people I talked to at Transportstyrelsen has been very kind and with the approach "it's fixable"...

/BKE

PerlanSwed Posted at 2015-6-25 00:29
Any news on possible reduction on kinetic energy to 150J so we can have P3 in UAS 1A class (Sweden)? ...

BTW, I did asked:


In the Matrice 100 specification you list:
the 22 m/s (ATTI mode, no payload, no wind)
17 m/s (GPS mode, no payload, no wind)
Have you any data for the Phantom 3 in GPS mode? As you only list speed in ATTI.



answer:


Blair.Tang (DJI)
Jun 12, 14:50
I check it with our R&D colleagues and in our database but sorry to tell that we do not have the accurate data for the Phantom 3 in GPS mode.
All i can tell is that it will be smaller that 22m/s.
Sorry that i can not help for this issue.
With best regards
DJI Product Application Technical Support

ad6 Posted at 2015-7-1 06:14
BTW, I did asked:

OK, so I got trough the process after presenting a detailed study of the modifications. Granted a flight permission UAS1A and the same day an insurance (1.295 SEK), just took two days in administration! I am awaiting the final paperwork but all is clear :-)

If of any interest I can specify the modifications (later the final 3D .stl) here or by private mail to help other Swedes stuck with the kinetic limits. ad5 dot runtime dot net.

/BKE

ad6 Posted at 2015-7-9 01:49
OK, so I got trough the process after presenting a detailed study of the modifications. Granted a f ...

Hi.
I am very interested in the modifications you have made and would be very happy if
you could explain a little more in detail about that.

There is also a new Swedish facebookgroup for DJI fans https://www.facebook.com/groups/115765918761991/
It would be great if we could get many members and discuss Swedish "problems and solutions" in Swedish.
Thanks/ Jörgen

I'm also from Sweden and interested in how you got UAS1A!

ad6 Posted at 2015-7-9 01:49
OK, so I got trough the process after presenting a detailed study of the modifications. Granted a f ...

I'm interested in the modifications you did as well! Would be great to see a couple of pictures and some detailed information about what modifications you did to get the UAS1A certificate.

/Majk

Same problem here, it's not only in Sweden, it's for the entire EU.
But it only applies when using the drone for professional use, hobbyists etc can still just go by the "informative" rules.

At the moment, I'm paying twice that in insurance because I'm at 163.8 joules   stupid drone speed.

very interested in your modifications.

I would love to get the modifications too, live in sweden and was hoping to use the Phantom 3 i UAS1A

No guaranties, but here it is. This modifications together with some serious measured stats and graphs in a PDF is what made Transportstyrelsen to accept the P3 as a UAS1A class vehicle. I have no idea if my resume (earlier experiences working with control towers in TIZ/TIA) and references had any influence.

As in my earlier idea I covered three sides of the 'box' surrounding the camera. Figuring out how much needed to be covered I tested first with some duct tape.

The final version is 3D printed with some small hooks that hold the thin air-brake to the legs as shown 40mm height and aligning with the lowest part of the body. The weight is neglectable. I may put up the .stl on thingiverse.com later.

The P3 behaves nice and the only noticeable  difference is a slightly tilted angle att full throttle. But as the aim (for me) is still photo at a maximum height of 50 meters that is no problem.

If windy with hard gusts I can see that video could be troublesome. But the cover attaches and removes in a flash.

Good luck! / BKE  (and sorry, I don't do Facebook)

ad6 Posted at 2015-7-29 17:07
No guaranties, but here it is. This modifications together with some serious measured stats and grap ...

Hi!
I am trying to get a license as well in Sweden and it seems to go well
Thanks a lot!

One question though. Is it possible to use the DJI Assistant app to adjust speed instead?

Reduce your speed.  Easy to do in this case.  Buy a set of 9443 Self Tightening props from the Phantom 2.  Same self tightening thread pattern.  Smaller prop.  May be exactly the decrease you need without having to modify any parts on your bird.
http://store.dji.com/product/e300-9443-props-red

simon.enelesfil Posted at 2015-10-1 06:06
Hi!
I am trying to get a license as well in Sweden and it seems to go well
Thanks a lot!

Cant limit in app unfortunately. :/   I suggest buying the 9443 props that were made for the P2.  Smaller prop. Less thrust.  Probably exactly what you need.

In my mind, adding the drag with the air brake will work the rear motors even more than normal, assuming mostly forward flight.  It would be nice if you could lower the maximum joules without adding any drag.

Can you adjust the throttle curve and reduce the full deflection amount? That way you'd be not at full throttle when the stick is fully forward.

ad6 Posted at 2015-7-29 16:07
No guaranties, but here it is. This modifications together with some serious measured stats and grap ...

Wow, great idea. Would it be possible to buy one 3d-printed box from you? I'm having the same issue with registering it as a UAS1A-class vehicle but don't have the equipment to create a box with a 3d-printer myself.