Motorized FDS trim wheel - detect manual pitch trim mode

[fisfro]

Hello,

I'm developing a driver for connecting the FDS motorized trim wheels to JH. I hoped that I can use the offsets 73A5 and 78E9 for this. It seems that this offsets are not working in standard configuration (with no other supported trim wheel connected). So I haven't seen any data on this offsets.
Okay, so I have used the trim data from FSUIPC to control my wheel during flight, which is working so far now.
Now I want to realize the "man pitch trim mode" and I want to ask, if there is an offset for this mode provided by jh or do I have to use the offsets for ADIRS, ELAC,SEC and FAC to create my own logic for detecting the case, when usually "man pitch trim mode" has to be active?

Thanks in advance!

Robert

[jeehell]

Hi,

Don't use the 73A5 offset, it has been replaced by 73AE due to collision with an already assigned offset...

MAN PITCH TRIM cannot be user triggered, it has to be because of failure/mis configuring the OVHD systems.
If the trim is not taken over by my software, the offset 73AE will read -9999.

Regards,
JL

[sstusek]

Bonjour Jean-Luc,

I am also interested in this motorized trim wheels topic. I've been fairly successful with offsets 73A5(now 73AE) and 78E9 in SIOC, got the trim wheels turning. I am not quite sure what is the role of offsets 73CC-13 and 73CD data pipe with trim wheels?
Thank you for your clarification and assistance.

Regards,
Simon

[jeehell]

The trim threshold determines how much out of synchronization you can get between FMGS calculated trim, and physical wheel position, before the AP gets disengaged.
This is mainly to allow enough time and counter any accuracy issue in the wheel positioning (both motor time to put the wheel in position, as well as the potentiometer accuracy).

JL

[sstusek]

Hi,
Ok, if I understand correctly, trim threshold is allowable trim wheel error value. If I encounter unexpected AP disengagement due to trim wheel position error (slow motor or unaccurate pot), I should increase trim threshold value. Otherwise, if it works, I can leave it at default 1 degree?
Thanks.


Regards,
Simon

[jeehell]

Hi,

Thats it!

JL

[fisfro]

Hi,

Don't use the 73A5 offset, it has been replaced by 73AE due to collision with an already assigned offset...

MAN PITCH TRIM cannot be user triggered, it has to be because of failure/mis configuring the OVHD systems.
If the trim is not taken over by my software, the offset 73AE will read -9999.

Regards,
JL

Hi,

so if I understand the trim handling right ->
The requested trim position (the set value for the wheel position for the control loop) I will read out of the offset 73AE and the current position of the wheel I will write to offset 78E9 .
I'm afraid that I still have not the point because I will read only "0" from offset 73AE during whole fligth and also if I will produce "man pitch trim mode" by switching off the flight computers I will not read -9999 from 73AE - only "0".... :-(

Robert

[jeehell]

Do you have the last version?

[fisfro]

I'm runing B44.0 - should it work in this version?

[jeehell]

no. Latest is 44.4

[fisfro]

thanks a lot - just updated to the latest version and FDS trim wheel is working now during flight as expected.
I have only one further question:
After touchdown you will set -9999 to the offset 73AE and therefore I set also the trimwheel into manual mode. But this will avoid, that your software will set trim to "0" and so the trimwheel doesn't rolls back to "0" quiet after touchdown.

So if the trim-value will be "3" during touchdown - the value will remain in your software also because the trim wheel will write the current position with "3" to offset 78E9 at that moment the driver will receive the -9999.

Should I avoid update to offset 78E9 of trim position for a specific time after touchdown?

Thanks in advance!

Robert

Edit: it seems that you will switch to manuel trim mode before touchdown - I will receive -9999 a few seconds before touchdown.

[jeehell]

The trim resest is a bit broken for now, I need to work on it.

JL

[fisfro]

No problem, I will implement a little workaround in my driver which will set the trim to zero after touchdown without regard to the -9999 info from the 78E9 offset....

Thanks for support!

Robert