Anybody flown helis (single main rotor) with baro or GPS modes?
« on: September 24, 2018, 11:20:56 pm »
There really isn't much place to mount a baro that is away from the main / tail prop blast.

After I get it flying with Basic AttiEstAlgo in Attitude I'm wondering if I will need to change the EKF settings to ignore the baro to be able to use INS13 AttiEstAlgo.

As an aside, given Bernoulli's principle it may be possible to design a vertical tube around the baro that would have lower pressure due to the airflow, then modify it into a slight funnel shape to increase the pressure back to normal atmospheric pressure.  More simply, first protect the Revo from the main blast, then if the baro is seeing increased pressure, put a roof over it, or if it is seeing decreased pressure, put a basin under it.

karla

  • *****
  • 629
Re: Anybody flown helis (single main rotor) with baro or GPS modes?
« Reply #1 on: September 25, 2018, 02:31:10 am »
Hi Cliff,
glad to hear you are picking up a heli again :)

I have a Revo Nano mounted in standard orientation (upside pointing forward) inside the bottom plate of a Trex450 frame.
I have  flown many times in AltitudeHold and AltitudeVario using INS13 AttiEstAlgo, and it works great. Very stable with small altitude corrections.

Here is a picture of the mount.
You can barely see the Nano board inside there.
Its pretty easy to access it later on, just unscrew the landing gear and open the bottom plate.



You can get a full sized Revo board inside a 450 size heli as well but it needs to be mounted in a different orientation. With a Nano you have more options for mounting.

Re: Anybody flown helis (single main rotor) with baro or GPS modes?
« Reply #2 on: September 25, 2018, 05:08:19 am »
Thanks.  That's good to know.  I guess it's like quads.  You've just got to deal with whatever issues you find, but you've told me that baro can work on a heli.  :)

I have several of the exact same quad kit that even run the same size prop.  The kit has a slightly larger base plate and smaller top plate (both are perforated) and is open all around from the side.  I always put the FC between the plates.  I had problems with one build, maybe because it has taller, slightly more powerful motors, though I don't really notice a power difference in flight.  Air blast was hitting the larger bottom plate and moving sideways to pressurize the center section.  Higher pressure; it thinks it is too low; it adds power; even higher pressure...  On that build I sealed the sides and the problem completely went away.

I can't guarantee I will get it done, but I had a nice nitro TRex-600 given to me and I am afraid of it for several reasons.   :-X  I would be more willing to try it out with full Position Hold available.  Of course I intend to learn LP heli setup with something more like a cheap 300 to 400 sized electric heli that I also have a couple of.
« Last Edit: September 25, 2018, 05:13:35 am by TheOtherCliff »

karla

  • *****
  • 629
Re: Anybody flown helis (single main rotor) with baro or GPS modes?
« Reply #3 on: September 25, 2018, 06:30:44 am »
I see.
Yes, a well tuned position hold is very nice to have.
Just to know its available provides a sense of comfort and relaxing.

That will also require a gps and compass though.
I have still not succeeded to get my Librepilot heli to a good position hold.
It does hold position but its too much "toilet bowl similar" motions to be trusted.
Really have difficulties finding good flying locations here so project is really slow.

Good luck!