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witek
09-01-2017, 09:40 AM
Hello Guys,

I have Vision 380 installed in my RV7A and unfortunately the pitch servo is working in opposite way. I did the ground test and roll servo reaction is correct but in case of pitch servo the reaction is opposite.
What can be wrong? I have not found information in the installation manual regarding cables which I could reverse - like in case of roll servo.

Any recommendations what should i check first.

Thank you,
Witold

Auburntsts
09-01-2017, 09:51 AM
Look at the wiring pinouts listed in the manual -- the info you're looking for should be there.

Don't know about the Vision specifically, but my on my TruTrak GX Pilot you either add or remove a jumper between the pitch control wires at the control head to reverse the servo direction.

jbDC9
09-01-2017, 10:44 AM
Look at the wiring pinouts listed in the manual -- the info you're looking for should be there.

There's an easier solution... I ran into this recently on my install, but it's an easy fix! It's a set-up function; see the Vizion install/Ops manual, page 14; a yes/no selection to reverse servo motion.

witek
09-01-2017, 12:43 PM
Thank you John,

I read 2 times the manual and did not find this information :mad:

Witold

There's an easier solution... I ran into this recently on my install, but it's an easy fix! It's a set-up function; see the Vizion install/Ops manual, page 14; a yes/no selection to reverse servo motion.

1001001
09-01-2017, 01:04 PM
There's an easier solution... I ran into this recently on my install, but it's an easy fix! It's a set-up function; see the Vizion install/Ops manual, page 14; a yes/no selection to reverse servo motion.

Wow, that could be scary--a software selectable servo direction. What if a software update were to reset the default to the opposite selected for the airplane? I would make sure to verify proper direction of the autopilot after making any change to the programming. Hopefully, they have some safeguards built in for that, but it does present a potential risk.

Perhaps I'm misunderstanding, though.

witek
09-03-2017, 03:35 AM
Thank you. It works perfectly now :D

pa38112
09-03-2017, 08:44 AM
[QUOTE=1001001;1200871]Wow, that could be scary--a software selectable servo direction. What if a software update were to reset the default to the opposite selected for the airplane? I would make sure to verify proper direction of the autopilot after making any change to the programming. Hopefully, they have some safeguards built in for that, but it does present a potential risk.

Perhaps I'm misunderstanding, though.[/QUOTE

I like this feature. The direction is dependent on the installation, so this way you wire it one way every time and then set the direction. That is the reason you do a ground test, and would do one after any update even if this option were not available.

Timberwolf
09-04-2017, 02:30 PM
Wow, that could be scary--a software selectable servo direction. What if a software update were to reset the default to the opposite selected for the airplane? I would make sure to verify proper direction of the autopilot after making any change to the programming. Hopefully, they have some safeguards built in for that, but it does present a potential risk.

Perhaps I'm misunderstanding, though.

I would hope as a prudent owner or mechanic such a thing would be checked on the ground, or at the very least in VFR conditions before trying to go IFR with a whole software update. If it doesn't react the way you expect you turn off AP, fly the damned thing, and figure it out on the ground. Either way, I think that's blowing it out of proportion thinking it's a preposterous idea to have software be able to change such a thin.

1001001
09-04-2017, 06:07 PM
I would hope as a prudent owner or mechanic such a thing would be checked on the ground, or at the very least in VFR conditions before trying to go IFR with a whole software update. If it doesn't react the way you expect you turn off AP, fly the damned thing, and figure it out on the ground. Either way, I think that's blowing it out of proportion thinking it's a preposterous idea to have software be able to change such a thin.

I didn't say it was preposterous--only that it represents a risk that needs to be mitigated.

rleffler
09-05-2017, 06:49 AM
I didn't say it was preposterous--only that it represents a risk that needs to be mitigated.

To accommodate the new switch that allows the AP to level the wings and fly the current heading, they had to free up some pins or move to a larger DB connector. The end result was to eliminate the servo direction jumper and implement it software.

Personally, I prefer it over the jumper. It shouldn't cause anyone concern, nor is it a risk. I assume that everyone validates all their settings after any firmware upgrade, then conducts a test flight. Correct?

TruTrakAndrew
09-05-2017, 09:00 AM
As Bob said, we had to make a choice with hardware vs software for pitch servo reversal with the new features added to the Vizion.

Glad that you got it working properly.

For future reference, there should also be some standard starting settings for each aircraft type (at least for all of the RVs) in the back of the installation manual.

Thanks!

1001001
09-05-2017, 10:56 AM
To accommodate the new switch that allows the AP to level the wings and fly the current heading, they had to free up some pins or move to a larger DB connector. The end result was to eliminate the servo direction jumper and implement it software.

Personally, I prefer it over the jumper. It shouldn't cause anyone concern, nor is it a risk. I assume that everyone validates all their settings after any firmware upgrade, then conducts a test flight. Correct?

I don't want to get in a semantic argument, but it is most certainly a risk, and that's why one does a validation and test flight. If it wasn't cause for concern, why would anyone check it out before flying? My point was simply that it represents a risk that should be mitigated.

jbDC9
09-05-2017, 12:12 PM
I don't want to get in a semantic argument....

Too late, you're already there. There may be a slight risk involved here, but that's why we check it before flight and then test fly it. If it gets weird in flight, turn the a/p switch off... no big deal, just fly the plane.

rleffler
09-05-2017, 02:45 PM
I don't want to get in a semantic argument, but it is most certainly a risk, and that's why one does a validation and test flight. If it wasn't cause for concern, why would anyone check it out before flying? My point was simply that it represents a risk that should be mitigated.

The same is true for everything else in your aircraft as well. The risk, although minimal, is due to making a change. The risk isn't that the function is implemented in software. The risk is similar for any component of your aircraft that you make a change.