Re: Collective jumping
« Reply #15 on: March 19, 2018, 11:56:58 am »
Ok, so i missed what you were trying to say about the min. I reset that and things are acting better. I will let you know. I think that my be part of the issue not i just need to go through and reset up eveything.

Does the throttle neesd a low min too? Or just the collective.

Thank you so much.

mr_w

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Re: Collective jumping
« Reply #16 on: March 19, 2018, 12:40:05 pm »
hi,
I have double checked what I did on my setup, and I have to correct myself, it is not V shaped but this:



This has given me nice positive and negative collective.. or at least I believe it does so :) (the thing actually flies).

Re: Collective jumping
« Reply #17 on: March 19, 2018, 05:37:09 pm »
Need both throttle and collective to have neutral set very low.  Reasons:

I think what we have learned is that for the default setup, when the throttle stick on the transmitter is above zero, but below neutral, then all the channels are set to their neutral settings.

It sounds like you had a low throttle neutral, but a middle collective neutral, so the first little blip of throttle made the collective servo go to it's neutral (middle), but adding more throttle stick made collective go to where you want collective to be.

karla

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Re: Collective jumping
« Reply #18 on: March 20, 2018, 02:06:40 am »
@Brad,
I dont think you need to redo all the setup.
Just remember every time you need to redo the transmitter calibration you need to put the neutral back to min.
That change will cover it.
(but of course you still need to level the swashplate travel and set up correct angles for cyclic and collective :) )
Let us know how things develop!

@mr_w,
when the Collective Pass through is checked, in Vehicle, Helicopter, Basic settings, CCPM options,
then I don't think it matters how that curve look like. It will use whatever the transmitter is sending right?
I think the setting of the mixers (Collective, Pitch, Roll) just to the right, will have most impact on a good enough range of the collective.
« Last Edit: March 20, 2018, 02:29:27 am by karla »

mr_w

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Re: Collective jumping
« Reply #19 on: March 20, 2018, 09:28:58 am »
@karla

Yes the curve actually matters, it is applied to collective channel. I suppose it would be helpful if there was title above the curve which says so.

It looked like for -1,+1 range, collective goes (with jumping) twice through all positions, so without digging further into the code, I just assumed that something in mixer is doing abs(collective) (or equivalent), and then applied this curve to scale -1,+1 to 0,+1.. which kind of fixed it. I am also pretty sure that this can be properly fixed somewhere else. Just thinking if this is common issue with heli setup? (this is my first and only heli with LP so far, but I have done plenty of multirotors and couple of wings).


karla

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Re: Collective jumping
« Reply #20 on: March 20, 2018, 10:14:54 am »
Thanks a lot for verifying that the curve still has impact!

Its not really any issue when setting these Helis up (other than the default collective setting neutral to mid of min and max).
Since, once you check the Collective Pass through, then you will work on the transmitter only and adjust it to what ever that curve is looking like, until you get the desired movements on the pitch angels on the rotor.
« Last Edit: March 20, 2018, 10:52:12 am by karla »