Piccolo Questions

I'm 80% done building my Fun Piccolo and have a couple of quesitons. Why does the rotor head have to pivote back and forth on the bearings? Is it part of the cyclic? I'm just not getting the physics behind it. It seems the swash alone would give all the movement necessary. Second, is the stock motor a plain 6v speed 280? Thanks.

[pgoelz]

It's a little complicated but the basics are that the swash moves the flybar paddles. This causes the flybar to tilt in response to the cyclic. Since the flybar is connected to the head, this causes the head to tilt, causing one blade to increase pitch while the other decreases. This generates lift that changes direction to follow the tilt of the swash. And THAT causes the heli to tilt in response to the tilt of the swash. This setup where there is no direct connection between the swash and the main blades is called "Hiller" as opposed to "Bell" (swash controls the blades directly.

There are other gyroscopic and misc. effects but that will do for starters.

The G295 is very similar to a 6V S280, but we all think it is missing a couple winds and is therefore slightly hotter and more suited to operation on 7 cells (the stock Piccolo pack). I have used a 6V S280 and it works but the 295 is noticably better.

Welcome to the fold!

Thanks for the quick reply. So am I correct in understanding that the pitch on either blade will be the same at a given point in the roation. Meaning does the pitch of blade one = x as it passes over heading Y on the compass, AND the pitch of blade two also = x as it passses over that same heading Y? I've been running the head without blades real slow trying to prove how this thing works to myself, but its still very complicated. Thanks again.

[Qema]

I don't have a clue how it works. I am just happy when the little bugger stays in the air till it runs out of battery power. [img]/ubbthreads/images/graemlins/smile.gif[/img]

Rest assured, there are some great minds here on this BBS. I dare say I am willing to bet any of your questions can been answered.

Oh, and welcome to the Friendly Skies neighbor.

wstrouse you could do worse than read Colin Mills articles, they don't go into the gyroscopic effects deeply, but give a flavour of how complicated the subject really is.

Colin Mills articles

You can reduce the url to get the rest of the articles.

is ANKS on the trade list?

whoops wrong post, sorry!!!!

[gaanel]

What is also confusing is the gyroscopic precesion (sp?). I am no physics major either. Basically the control input is 90 degrees before the force takes place. Say if you want to do a roll to the left. Looking down at the helicopter with 12:00 Oclock at the nose, 3 Oclock at the right side, 6:00 Oclock at the tail and 9:00 Oclock at the left side. A control input to roll to the left will actually make the flybar at the 12:00 position angle up for increased lift. However, the flybar paddle will not actually pitch up until it gets to the 3:00 position, 90 degrees after the control input. The flybar then pitchs up which causes the head to rotate which causes the blade at the 12:00 position to angle up. Again, the blade will not actually pitch up until it gets to the 3:00 position, 90 degrees after the control input. This is simplified but it goes something like that. So when the helicopter is static it looks like a left cylic input would actually make the helicopter go backwards. Kind of neat when you think about it.

Oh also to get a "feel", rather than a dry mathematical point of view, for what the forces do, hold the picc in one hand and spool it up (probably best only to do this on the FP) then mess with the cyclic controls. You'll feel the forces (which I found surprisingly strong) and the delay in response.

Be careful!