Odd slow taxiing behavior…
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There is no Superman here , just algorythmic convergence issue which is normally catched by a motion detection code that rounds values to zero in those situations and keep ac static
For a reason I can’t explain there is an issue on your rig……
Could also be a bump value not’correctly inited
Difficult for me to fix if I can’t repro this myself
Does it happen to you in a fresh created TE ? With any f16 variants ?
I agree– the motion detection code is NOT catching this crabbing, and so it’s not keeping the aircraft static.
You say it’s my rig (!!!) I say it’s the code. And I say that the reason you can’t repro it is because you aren’t being patient enough with your slow starts/stops at idle on the ground. It takes a few attempts to induce the crabbing. And remember: brake to a stop and then release the brakes and let it sit there for a moment.
I didn’t test EVERY F16 variant, but it happened with three different ones.
You know, this isn’t a deal-breaker. It’s easy to deal with-- all you have to do is apply the brakes and roll out of the crab motion. I just thought you’d want to know about it and take a closer look at your motion detection code, that’s all.
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OK SoBad; Thank you will try to repro on my side.
Do you also confirm Yaw Trims to Zero? Could you also try with no joystick/rudder (keyboard only)? That would be a useful info if I can’t repro.
Dee-Jay, will do and report back to you…
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I agree– the motion detection code is NOT catching this crabbing, and so it’s not keeping the aircraft static.
You say it’s my rig (!!!) I say it’s the code. And I say that the reason you can’t repro it is because you aren’t being patient enough with your slow starts/stops at idle on the ground. It takes a few attempts to induce the crabbing. And remember: brake to a stop and then release the brakes and let it sit there for a moment.
I didn’t test EVERY F16 variant, but it happened with three different ones.
You know, this isn’t a deal-breaker. It’s easy to deal with-- all you have to do is apply the brakes and roll out of the crab motion. I just thought you’d want to know about it and take a closer look at your motion detection code, that’s all.
It’s been 12 years I am coding and flying every day this code , believe me if I tell you I can’t repro it
I am not sure it is the motion detection code it can be plenty of other things
Do you confirm it happens to you on a fresh TE as well ?
I could make the filter bigger for motion detection but that could mean a small hiccup when starting rolling
I could also very slightly increase the initial friction
I wish I could repro it
and by the way, i’m not saying your rig is faulty, i am saying i cant repro and i know very small things can make things different
fact is you can repro it
fact is i cant -
ok
jsut to show you what i se eon my rig and what should be normal behavior
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On ground, wind data is displayed on DED when speed is above 70 lnots
I mean the “sensed” wind commuted by IRS. (on ground it shouldn’t be possible since no drift angles nor difference between ground speed and TAS or (if displayed) would not be a valid info.)
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and i am also able to replicate it , and this confirms what i was saying, multiple causes possible
this is not motion detection and algoryhtm divergence.
this happens when you release parking brake on a “bump” with minimal thrust. The bump is high enough to prevent from going FWD as the thrst is weak but the side slope of the bump makes the AC to turn along that slope (the front gear should rotate …).
Although this is physically possible (since the BMS code is 100% physics computed), i agree this is weird and i might figure out a way to prevent it
thank you for the report, and next time dont stop on a bump slope (i know you cant see them, but dont stop on them anyway ;p)
and when you say “it takes a few attempts” , that’s because it takes a few attempt to stop perfectly on a bump
FYI bumps are modeled as trapzoidal terrain , so dont stop on slopes, you can stop on the flat surface (a few inches lol )
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Mav & Dee-Jay - Thanks for your patience. Please see attached video. My rudder controller was disabled in this video, per Dee-Jay’s request.
The crabbing starts at the 2:14 mark, if you want to get right to it. This time, it crabbed to the left. I show both outside and satellite views of it.
Mav, I think you’re probably on the right track, but the front gear does NOT rotate during the crab (see outside view), and the motion is pure vertical axis through the CoG for approx. 20 degrees of movement with no forward motion (see satellite view), which is physically impossible for the aircraft (unless invisible Superman is involved ).
I hope the second video is a better example.
PS - It happened on a fresh TE and on a stock campaign.
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Mav & Dee-Jay - Thanks for your patience. Please see attached video. My rudder controller was disabled in this video, per Dee-Jay’s request.
The crabbing starts at the 2:14 mark, if you want to get right to it. This time, it crabbed to the left. I show both outside and satellite views of it.
Mav, I think you’re probably on the right track, but the front gear does NOT rotate during the crab (see outside view), and the motion is pure vertical axis through the CoG with no forward motion (see satellite view), which is physically impossible for the aircraft (unless invisible Superman is involved ).
I hope the second video is a better example.
You think I am on a right track ?
Good news I know I am on the right track LOL
As I said , the front gear does not rotate but it should , but it does not because of plenty of reasons I don’t need to explain here
So case is closed, thank you for the report. This issue may or may not be fixed in 3 to 4 weeks
In the meantime , don’t stop on a bump or if you do jump it with a little more pwr
And the side of’the Turn is dependant on the bump’shape since all bumps have different sizes and shapes (randomly)
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You think I am on a right track ?
Good news I know I am on the right track LOL
Mav, I was a programmer for 30+ years. I even wrote a silly tank artillery game back in the early 90’s that Walmart distributed for a couple of years, using state-of-the-art VGA graphics (lolol) and fairly elegant physics coding/modeling. I meant it as a compliment, not an insult, that you were able to so quickly narrow down the possible places in code to examine.
PS - Clicking your video in your previous post shows “Video Not Available”
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Speaking of Nose Wheel Steering…“?” I cannot seem to find that so I can taxi around on the parking area to taxi and turn off after I land. I have been searching everywhere in the menu for “Nose Wheel Steering” in 4.34.
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It’s on the stick, “missile step” which does several functions including toggle NWS when on the ground and AAR door closed.
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just for those who have not well understood
this is a bug
this has been fixedyou will have to wait 3 to 4 weeks.
thank you the OP since it would have been extremly difficult to catch without a proper video
this perfectly demonstrates why we need repro cases, since it’s difficult to understand specific bugs in writing …