Choosing a Heli
olly
I just wanted to drop the group a line and ask what people are
currently using/ their recommendations in terms of suitable platforms.
My UDB3 has been sitting on my desk for a good month or two now just
gathering dust and finally have a little time and money on hand.
I have my eye on a flybar Trex600 (http://www.rchobbies.co.nz/
product_info.php?products_id=1814) but being quite an outlay (around
$1,500/2000 nz all in) I just wanted to post to the group and get some
feedback/thoughts
Is there anything I might need to consider or that might trip me up?
I know very little about RC helicopters (or RC in general for that
matter). I note your post, Peter, on EMI interference etc and the your
recommendation for 2.4Hgz Spektrum technology last month.
Any other advice would be gratefully received.
many thanks to all for the brilliant work. A fantastic site.
PS - has there been any progress on the HIL plugin for helis? this,
for me, would be a great place to start. Although I note on the web
there was quite a bit of interest in 2005/2007 from what I understand
this wasn't feasible for simulation of the X-Plane heli. I take it is
your area Marcus? I would be keen to get involved if there is some on
going work in this area.
Kind regards,
Oliver
John McClelland
I am flying the TREX450. I have been thinking about the 600, but got side
tracked building a Quad right now. Both the 450 and 600 platforms should be
good but the 600 gets pricey. I am assuming you will go electric. There
are good build/tune videos on the net to help you setup your heli (look for
Finless videos). You will need a pitch gauge and some bubbe levels at a
minimum. I sugget watching them in advance of putting things together.
Then there are the LiPo batteries and chargers as you probably now by
now....it all adds up just to get in the game.
If you really do not have experience in flying helis, I stongly suggest you
get a simulator and practice...a lot. You are pretty much guaranteed to
crash without some simulator time under your belt. MP-H helps you learn
once you have the basics by providing stabilization in pitch and roll. but
if something goes wrong you will want to be able to switch to manual and fly
it yourself. Once you have some sim time and feel comfortable flying, there
arre some good tutorial sites you can go to and go through the basics.
I use the Spektrum system as well. I have the DX-7 Tx and AR7000 Rx (7
channel). I suggest you go with a 7 channel system. You will be able to
control Throttle, 3 Swash serrvos, Rudder, Rudder gyro gain, and Mode. Mode
is used for manual, stabilized, and navigation (future) in MP-H.
In principle, you could use 6 channels by using the Heading Hold function of
MP-H which bypasses the rudder gyro (in next release), but I think you may
want the option to fly with the 401 gyro as well.
HIL is not implimented for helis as far as I know. Marcs has worked on it.
It just hasn't got high enough on the TODO list.
In addition to the UDB3, you will (or might) need the following items:
Get a few extra main rotor blades, main rotor shafts, and tail rotors and
plan on replacing a few as you learn to fly!
There are crash kits out there, it just depends what access you have to
local hobby shops that stock heli parts. Ordering online can be more
expensinve with shipping and take longer to get what you need.
Magnetometer for Heading Hold (next release of MP-H) if you want to bypass
401
Ultrasonic and barometric sensor for altitude control (under development)
GPS (not needed until we include navigation)
Special cables for extra input/output channel for Heading Hold (you can make
them yourself)
We may go to PPM inputs in the future for extra channels.
OpenLog to log telemetry data in flight (very useful to diagnose problems)
Hope this helps,
John
olly
Thank you. I can go out now and buy with confidence. I note you (or
perhaps another individual in the group - I saw a pic somewhere not so
long ago of a chopper on 'training balls/kit' ) is using a flybar
model? Apparently the flybar-less are slightly more stable..?
In terms of flying skills I was thinking of trying something like this
(http://www.youtube.com/watch?v=IOCSNvJTaTs). Seems like a great idea.
If I have any luck I will post the part files (but then perhaps I am
getting a little ahead of myself. Best purchase the helli first
lol).
Incidently, I have come across some of your videos by chance on the
web. Fantastic, really helpful. I also note a few references to them/
others in the occasional thread. Is there a specific source/depository
where they can be found?
thanks for your time!
Olly
On Mar 1, 11:39 am, "John McClelland" <mcclelland.j...@gmail.com>
wrote:
John McClelland
in action. I think Jerry might have some sort of stand, maybe he will
comment.
I used the "training gears" (just 4 ping pong balls on rods) when I started
developing MP-H to give a little forgiveness if I came down hard in a tilt
(happened until we figured out the gyro saturation problem on the early
boards). They just keep you from tipping to a degree and getting a blade
strike. Cheap but only help up to a limit.
I think the flybarless models use something like the UDB to stabilize. You
might be able to go flybarless and use MP-H to do the stabilization, but I
haven't tried that and I suspect we would have to play with the gains to get
things right. I think the flybarless versions are a little more efficient
since they aren't turning the paddles and possibly quicker. I don't think
quicker is necessarily a good thing when starting out. You can always take
them off later once you get some experience on it.
I have put videos up in the past on Vimeo but they expire eventually. Once
winter breaks up here I plan to do some for the MP-H release and maybe the
Quad. Jerry has some quad videos.