karla

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Re: GPS assist and Heli
« Reply #105 on: January 23, 2018, 07:20:42 am »
Is RC control over telemetry also supposed to work on LP 16.09?

f5soh

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Re: GPS assist and Heli
« Reply #106 on: January 23, 2018, 10:46:57 am »
No, this feature is introduced with LP-548

karla

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Re: GPS assist and Heli
« Reply #107 on: January 23, 2018, 12:36:10 pm »
okay thats why :)
I think this is a really nice improvement.
Seems so redundant to have a separate PPM thing going separately while you have a perfect data communication going anyway with telemetry.
I have some unexpected results using it though and maybe I start a separate thread about this.
It feels very much worth it to get it running smooth.
Thanks a lot
Karl

Re: GPS assist and Heli
« Reply #108 on: January 23, 2018, 10:16:55 pm »
One of my new, cheap clone OpLinks has a 43khz AFC Correction shown when testing it with next.  That is more than a whole 40khz channel.  It seems to work better than expected in low power testing, but one of the things I noticed was that the Rx Level jumps back and forth from OK (say 50) to bad (say 75) without moving anything.

If I were to move these apart a little more, the 75 would turn into a regular drop out like you are seeing.

I suspect that the "channel order" of this device doesn't match the good devices.  "Off by one channel" would cause the 43khz AFC Correction, but maybe the "channel order table" (actually frequency synthesizer divisor) is wrong in other ways too.  I have played with the min and max channel settings (didn't help).  I could have tried different combinations of OpLinkSettings->HopChannel but I just grabbed a different OpLink when I found this problem.

f5soh

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Re: GPS assist and Heli
« Reply #109 on: January 23, 2018, 11:24:14 pm »
OpLinkSettings->HopChannel setting is related to OpenLRS, nothing to do with OplinkReceiver or OPlinkCoordinator usage.
In all cases the OpLinkSettings->HopChannel do not need changes at all, this is populated according to the OpenLRS binding and updated on binding.

In OPlink setup channels used for hopping are simply generated using min/max channels defined by user.
Since the limits are the same in both devices the channel list are the same and "in phase" in both devices.

Except if you are using low baudrates the frequency deviation (and almost channel bandwidth) is set as follow:
 100 kbps - 60 khz
 128 kbps - 90 khz
 192 kbps - 128 khz
 256 kbps - 150 khz

A AFC correction is not really a problem at short range but a Xtal tuned (aka AFC~0Khz) can help for quick reconnect when link is lost at larger range.

xfce

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Re: GPS assist and Heli
« Reply #110 on: January 25, 2018, 01:58:24 am »
Hi all,
does GPS assist flight mode have be supported by Heli now ?

karla

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Re: GPS assist and Heli
« Reply #111 on: January 25, 2018, 03:29:05 am »
Hi xfce, nothing has changed yet.
Still working to complete a successful position hold using Next.

The progress is
. verifying, setting and using Collective as Thrust and using Governor mode on heli ESC, this works as expected using AltitudeHold in Basic AttEstAlg.

The remaining issues for me are
. the RC control and telemetry is not stable, many unexpected failsafe's.
. vibrations must be sorted out before even attempting INS13 AttEstAlg and position hold.
. the compass had too much disturbances last time (have changed to a DJI unit now).

Please go ahead and try it yourself.
You need to change setting the FlightModeSettings > DisableSanityChecks to True.
Otherwise it will be a Red CONFIG.