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Artlav
11-20-2011, 12:30 PM
Continuing on the quest of achieving a fun and stable quadrotor, i now try to move forwards instead of upwards.

As the thing does the loop i walk below it.
That is quite disorienting at first - you glance down to assess the steps, then look up to find the quad drifting fast, then correct the flight and step into a hole, look down to assess the next 5 meters of terrain, look up to find the quad about to do some flips in the grass and so on.

I also implemented the Honk's old advice of scaling the throttle curve to keep 100% stick at 70% throttle.
That is a very useful thing to do, as it gives much finer altitude control instead of "release balloon" and "pop balloon" the regular way gives.
But it also takes getting used to when you need to slow a descent, for example.

Summarily, it was a slow and steady forward flight against the gusts of wind and inexperience:

http://www.youtube.com/watch?v=i7g21szuVvU

I really need an FPV rig...
Hate to choose between travelling and getting a quad upgrade.

Honk
11-20-2011, 07:56 PM
What were you trying to do? Forward flight against the wind while walking behind it?

I must tell you this about wind and multirotors: it's treacherous! It's hard to anticipate the wind, so therefore we wanna have as little "wing area" as possible against the wind and we want as much force as possible to fight the wind.

As little wing area as possible is accomplished by using smaller props, and besides getting less wing area (less wind influence) we also get a prop/motor that potentially can change RPM faster due to less mass.

The other thing, force, might be achieved by trying a Y6 or X8 setup, I think that might prove good against the wind. So if I were you I'd get some more motors/ESC's and some sets of smaller diameter props.

Artlav
11-24-2011, 05:00 PM
Treacherous it is.
The wind is mostly one way, but i don't really want any more to walk downwind from a flying, flexing quad that is only slightly controllable.

Smaller props means smaller quad, means less mass, means less wind resistance, no?
My small one can't stand any wind at all, and is only really flyable in a room.
Let's see how the new big one will behave, with much smaller cross-section.

Honk
11-24-2011, 10:08 PM
Smaller props means smaller quad, means less mass, means less wind resistance, no?
Smaller props = less wing area = less wind effect on craft... I think... :)

But smaller props != smaller craft I think. Smaller props = use more props. I think the Falcon 8 is a winning concept. It's got 8 pieces of 8" propellers in a V/H manner and can evidently handle wind exceptionally well.

http://www.youtube.com/watch?v=GgrAtQDyEAE

And it also isn't all because of software, this means the real hardware is mechanically able to handle it.

elchan
11-25-2011, 03:15 AM
Just a question, Artlav, what transmitter do you have? Did you remove the ratchet on the throttle, so that the action is smooth? Because, seems like a lot of your problem is related to operating the throttle smoothly.

Artlav
11-25-2011, 08:45 AM
Just a question, Artlav, what transmitter do you have? Did you remove the ratchet on the throttle, so that the action is smooth? Because, seems like a lot of your problem is related to operating the throttle smoothly.
Futaba T7C.
The throttle problems are mostly because i scaled the 50%-100% throttle to 50%-70% response and haven't got time to get used to it yet.
I tried to remove the ratchet by putting rubber tubes on it, but it scratches itself back after some time.


Smaller props = less wing area = less wind effect on craft... I think... :)

But smaller props != smaller craft I think. Smaller props = use more props. I think the Falcon 8 is a winning concept. It's got 8 pieces of 8" propellers in a V/H manner and can evidently handle wind exceptionally well.
Nice.
You'd think more props=more area=more trouble for the same wobble.

Kind of reminds me of this victorian era thing:
http://www.3dlinks.com/images/gallery/gallery3/L%27Albatros.jpg