Geolink drift

[Nmony]

Hello,

if vibrations are high then Stabi Correction ON will not work well, also for any other Stabilisation/Rescue mode.

Now it depends if you wish to check and fix the vibrations which as result will give the best results.
Or you can just leave Stabi Correction OFF or if the problem persist to enable Signal Processing - Extended.

In this section you can find the correct procedure when Drifting is happening:
http://manual.spirit-system.com/index.p ... g#Drifting
This is basically what we are trying to resolve.

You said that there was some success with previous settings, can you explain in a greater detail what was wrong exactly?
It should work so that when you engage Position Hold it will hold position (not altitude). It might be few centimeters until model will stop completely and there it will hold (approximately +/- 10cm precision can be achieved) if you are not touching sticks.

Hi

The only success I have had with Position hold was after I had calibrated the compass. I've watched a video you put on Youtube of this function and mine was not behaving like that, it was more like the Coaxial Stabi, which was activated at the same time, However once I landed and took off again then I had to use a lot of stick input to keep it level as below.

The issue I am having is that I currently have to hold nearly full right aileron and nearly full forward elevator when Position Hold is on or the heli will try to move back and left.

With just Coaxial stabi enabled the heli is very stable and easy to hover in 1 place with minimal corrections.

I have not tried to enable any other GeoLink features except Position Hold.

I'll try with Signal Processing - Extended and see if that helps.

I have a DJI Naza-H on an old Nitro heli with a flybar and that thing is rock solid stable when GPS mode is engaged.

Please let me know if you need more info, I can check the vibrations and post up the graph if that is helpful?

[Nmony]

Right, I changed the settings so that Signal Processing - Extended was on, and I turned off Stabi Correction.

I calibrated the Geolink compass then flew the heli.

Heli does not stay in one position, it flies the same as when in Coaxial mode - small corrections required to keep it in 1 position.

After 4 mins of flight the drifting started - it was pulling to the back and left, it took full right aileron to keep it level and land.

I disengaged Position Hold, re-positioned the heli and then re-enabled Position Hold. After 20 seconds of flight it was drifting badly again - Something is not right here....

[ZeXx86]

Thank you for your details.
Please send Vibration plot, this would be very helpful.
Indeed there is something really wrong.

It should be enough to measure Y and possibly Z axis, but ideally with tail blades on. (No main blades).
Before measurement please set tail blades so they have 0° pitch with your rudder stick.

[Nmony]

Here are the Vibration graphs, I'm sorry about the size of the images:

Z-Axix

X-Axis

Y-Axis

[ZeXx86]

Thank you very much for the plots.

The spike from rudder mechanics is unfortunately really high. Normal magnitude has 30 - 60% in all axes.
It look like bent tail shaft or unbalanced tail blades.

[Nmony]

Thank you very much for the plots.

The spike from rudder mechanics is unfortunately really high. Normal magnitude has 30 - 60% in all axes.
It look like bent tail shaft or unbalanced tail blades.

Shall I try running it without the tail blades?

[Nmony]

Without the Tailblades the vibration is under 30 - new set ordered along with a tailshaft.

Why would this affect the geolink when Coaxial seems to work well?

[ZeXx86]

The issue is almost always not in tail blades. Tail blades will only make the problem more apparent.
So buying new set will likely not help unless you can see a damage.

With no tail blades vibration level should be rather under 15% as there is virtually nothing that should cause them.

Could you please check the tail shaft? When putting at the glass there should be no deflection.
Ideally if Coaxial mode will work with Stabi Correction ON / Extended Signal Processing OFF it should all work perfectly and precisely for unlimited time.
With Extended Signal Processing ON there are certain limitations, yet it is more immune to vibrations.

It look like we will have to make it completely independent from model vibrations in next update.

[Nmony]

There is some damage on the tail-blades, new set on the way, this will take a few days to arrive.

I will run the heli up with out them and post the graph today - Tail shaft does not look bent but I will remove and replace.

[Nmony]

Here is the graph without the tail-blades mounted: