Central position trimmer problem

OK, I'm back with the problem. Where were we? ..............................

I think here

(...) did Viper use quick presses-releases? Yes. Did he use FD? No (...). And after hi hit his trim (without holding down) he didn't get any unintentional inputs.

Well, I tried today again thinking about trying the 'wrong trimming method' i.e. holding down the trim button. The problem is the bumps I get occur on the trim button press. Plus the above.

With FD on I get no bumps but it's not anywhere near being a solution.

I don't have that problem, everything works fine for me.

I don't have that problem, everything works fine for me.

Very, very weird then. But I'm done troubleshooting that sorry issue for now. Maybe I'll test it again the next time I reinstall my system. In the meantime I'll have to use the "holding trim" method and stay away from 300 kph as I get a bump as soon as I PRESS the trim button.

... as I still believe in many circumstances, you should :)

... as I still believe in many circumstances, you should :)

?

You should get 'the bump' when you press trim in a number of aspects and manouvers, from having by that action just neutralised and started afresh the influence over the control surfaces applied by the autopilot dampers (no longer holding you back from the course you've set with the cyclic, where you were essentially 'fighting' against the AP to set your current course). It seems natural enough, even if footage of it is scarce.

Nate

:music_whistling: but he is done testing this sorry issue for a while! :lol:

I know.. I should have known better, I know how I'd be in the same situation.

First off, there's a reason why normal procedure is to do short trim taps. It's plain to see if you could try both methods in the real aircraft. While holding down the trim button the spring tension is gone. Have you ever tried to fly a flight sim with a joystick that didn't have a spring in it? It sucks. A lot of what makes a joystick usable is the artificial feel (as it's called) spring.

Transients are happening because of sudden changes in autopilot input (these "bumps"). You're flying along with the AP providing some +17% AP input along a channel which is being applied post-pilot input. You press the trim button. This AP input must be rest back to 0% or the AP authority won't be symmetrical after the next capture. Releasing this authority is going to be a bit of a bump.

What's potentially not modeled correctly is the relaxation time associated with this AP authority re-centering. The AP channel can't go from +20% to +0% authority instantly. It's a hydraulic actuator which is a physical system and takes time to move. Additionally Kamov may have purposefully slowed down this process to smooth flight. In the computer simulation world these considerations require deliberate effort on the part of the coder which may or may not have happened.

It's all nice but have any of you compared bumps during my flight to the bumps Viper is getting (practically none)? http://forums.eagle.ru/showpost.php?p=987218&postcount=10

Also my response to Viper as a reminder

I thought so - you don't get any input bump after each trim :(

I get a bump every time I trim in the direction my controls are moved to. Note that the bump is not mirrored in the controls position indicator Rctrl+ENTER!

O.K. well the autopilot is always trying to get you back to the state of bank pitch and roll you last trimmed for, so whenever you trim, those controls are released, so there will always be some sort of jump. I just press and hold, so I can somewhat avoid the problem.

Please read the post #60 again :) Or record a vid if you get bumps too on TRIM PRESS.

Viper and your track/video look like the same behavior.

Really? :) I'll have to take a look at both again.

The possible bug re-cap:

I get a bump every time I trim in the direction my controls are moved to. Note that the bump is not mirrored in the controls position indicator Rctrl+ENTER!

- the joystick quality was as good as it gets - X-52 Pro with hall sensors mod

- tested with X-52 Pro, rudder axis unmapped, rudder pedals disconnected and using a [T] key instead of the trimmer mapped to the a joy button

- tested with the same as above but with Saitek AV8R-01 (also good potentiometers)

- DCS BS version - the latest for the time of the recording

- Windows 7 x64

the video recording:

Aviator test:

Same behavior!

http://www.mediafire.com/?j2njwvjb2skuty0

and

what I observe is not a bug only if real Ka-50 pilots get the bump too.

(...) did Viper use quick presses-releases? Yes. Did he use FD? No (...). And after hi hit his trim (without holding down) he didn't get any unintentional inputs.

Quick comment - To use the Trimmer without the Flight Director on requires you to press the trim, manoeuvre to the pitch and attitude you want to maintain and only then release the trim.

 

If you fail to do this (and do it very often) you will see uncommanded pitch and roll inputs as the autopilot authority is reset (ie stick position + 20%). This 20% reset is what you are seeing, and it will not show in the Ctrl-Enter indicator as it is the autopilot entering this input. The Trim is not intended to be used as a quick stab and release due to the coupling of the autopilot and the cyclic centre position reset.

 

This is why I prefer to fly with the Flight Director on if I have any sort of manoeuvring to do. The Flight Director will allow you to use quick stab trimming if you like, as the autopilot is disconnected.

 

Nate

At first there doesn't seem to be a problem to me, a little bounce when trimming is not unusual.

 

What I did notice is that you are not flying symmetrical. The "ball" is out of the center and it looks like the more it is, the greater this bounce is.

 

This could be eigther the flightmodel, or a little bug in the flightmodel. Besides the a-symmetric flying, I don't think you do anything wrong.

 

Will need to test this myself.

 

Greets,

Fraz

maybe...

Transients are happening because of sudden changes in autopilot input (these "bumps"). You're flying along with the AP providing some +17% AP input along a channel which is being applied post-pilot input. You press the trim button. This AP input must be rest back to 0% or the AP authority won't be symmetrical after the next capture. Releasing this authority is going to be a bit of a bump.

 

What's potentially not modeled correctly is the relaxation time associated with this AP authority re-centering. The AP channel can't go from +20% to +0% authority instantly. It's a hydraulic actuator which is a physical system and takes time to move. Additionally Kamov may have purposefully slowed down this process to smooth flight. In the computer simulation world these considerations require deliberate effort on the part of the coder which may or may not have happened.

Just wanted to add my 5 cents to the mix. Many people have mentioned on this forum that in BS2 the trimmer is different. There are known issues with FF joysticks, however testers do not acknowledge issues with normal ones. Perhaps not all sticks experience the 'bump' thing, however from what I can see the Saitek X52s have this problem. I have it, a few other people have it. Frankly speaking BS2 is unplayable on my X52. At first I figured I'm doing something wrong, not trimming properly or not often enough, but in BS1 I have zero issues - I can fly fast, aggressive and the helicopter does not act as a drunken hippo on speed. And I'm not even what most people would call a descent pilot. If we add wind to the mix (Medved 2 campaign is a bad weather fest all the way, ground control refuses engine start-up most of the time, not to mention flying) the sim is unplayable.

If we add many minor bugs (clipping gear, NVGs and other) and combine in with the fact that 1.1.1.0 has some serious performance issues for no apparent reason - 20$ for a patch that actually breaks more stuff than fixes (at least more crucial stuff like the trim) it's a bad deal altogether. I'm sorry to say this, I have always been an enthusiastic ED customer, but I simply feel ripped-off.

Escalating expectations is not a good thing. But we are all buying their next product anyhow are we not... ;-)

I have not read through your whole thread (seen enough complaints). Have you tired a larger deadband setting? Sounds like that could be causing it.

however testers do not acknowledge issues with normal ones....

Absolute rubbish.

Testers have provided adequate explanations of the said behaviour. I for one acknowledged the issue to death. The forum is littered with the virtual ink of my replies in various threads, together with tracks and illustrations etc etc. Then again, why listen to me? Move along, nothing to see here......

Have you ever considered the possibility that you have been doing it wrong in BS1? It is clear that you do not understand the trim/AP systems as well as you should. Have a look at the replies by the various testers in the threads and you'll find the answer you are looking for.

.....the sim is unplayable......I'm sorry to say this, I have always been an enthusiastic ED customer, but I simply feel ripped-off.

Nothing that more practice/flight hours will not cure. If you are unable to put in the time, the SIM is scaleable. I would suggest you tick the 'GAME AVIONICS' mode. As for being 'ripped-off', it's hardly fair to blame the SIM for shortcomings, no?

Problem with the weather? Edit it in the ME! 1 min and you're done......It's not rocket-science.

Viper, I understand your arguments, but I just feel lost in all this. Yes, I have read most (if not all) of the stuff on trimming in BS, yes I have considered the possibility of doing stuff wrong in BS1, but then again I have been doing it according to what I saw on the forums and in the developers release notes movies and various other YT videos. I have seen tracks and read your posts, but whatever I do, I still have the bump unless I fly using the pres-hold-release method and as far as I know, this is not the proper way to fly the Shark.

I did put time in BS1 and I also put time in BS2. I do not intend to switch to "game mode", since I do not see the point of playing a study-sim this way, not to mention all the time and effort I put into learning this sim would go to waste. I may not be an active member of the community, but I am fairly proficient in operating all the systems in the sim and the only thing that I find difficult is controlling the helicopter itself (in BS2 not BS1).

From what I have read here and there, it was only confirmed that FF joysticks are broken and issues with normal ones are just are result of "you're doing it wrong". Yet there was no developers release notes, new tutorials or even a mention that flying the KA-50 in BS2 is now different. I'd gladly spend more time learning to fly if I had any clue as to what I am doing wrong.

As for being ripped off, I do not understand what do you mean about blaming the sim for shortcomings. I you are addressing the issue of paying 20$ for a patch that has shortcomings and the customer dissatisfaction that goes with it, I would say it's quite fair.

It is not my intention to argue with anyone, however, it's a fact form me that whatever I do in BS2 I cannot get rid of the bump, where in BS1 the issue does not exist. I have tried to do everything I saw in the tracks and videos you have posted, but it just does not work for me - bumps still happen and unless I fly with the press-hold-release method, I am all over the place. Changing axis settings also does not help.

I'll post it again, hold down the trim, make your course, speed, height adjustments and release. Is anybody that uses the hold then maneuver method having issues? no bump, no fighting with auto pilot nothing. when using FD you don't even have to hold the trim if you don't want to, just maneuver then click.

I know the real way of using the trimmer is the real way :) but it's causing non-stop trouble for people. just use the hold trim method and enjoy your brand new tame black shark.

.....I have tried to do everything I saw in the tracks and videos you have posted, but it just does not work for me - bumps still happen and unless I fly with the press-hold-release method, I am all over the place. Changing axis settings also does not help.

The only assistance I can offer is for you to fly a circuit or two illustrating the problem you have and post the track. I can then replicate your flight parameters and offer possible 'habits' that negate the 'bump' you are experiencing.

I'll say this again - I am not stating that my way is the correct way. It is merely an interpretation of how I understand the issue. As I have illustrated in other posts, a lot of issues are being experienced due to the fact that trim is not attended to often enough, when needed. Adjustments that are made are too large for the SAS system and AP system to handle all at once, resulting in the additional input experienced. A good example would be the 'trim for altitude' track - you cannot trim for a 10m/s climb with one trim-immediate-release: It takes approx 8 trim inputs to trim for those flight parameters. It is little wonder that the deviations are experienced when trimming puts the SAS and AP systems under such workloads.

Another aspect to keep in mind is that it is not always necessary to trim for every flight parameter deviation, provided that you are trimmed correctly to start with. Extreme evasive maneuvering can be undertaken without trimming at all - it all depends on the circumstances.

I know the real way of using the trimmer is the real way :) but it's causing non-stop trouble for people. just use the hold trim method and enjoy your brand new tame black shark.

And I find it works exactly the opposite for me, with FD on and hold trimming I'm constantly fighting the aircraft while with lots of small trim adjustments and no FD I get the aircraft do to exactly what I want it to do. Just so many ways of flying! :)

And I find it works exactly the opposite for me, with FD on and hold trimming I'm constantly fighting the aircraft while with lots of small trim adjustments and no FD I get the aircraft do to exactly what I want it to do. Just so many ways of flying! :)

yea i don't hold down the trim while using FD, just saying you can if you'd like. When using AP though i use the hold down method and I get no bumps bruises ect ect that people are having problems with. If you can correct your issues by changing the way you fly a little bit and it works, problem solved :thumbup: I promise Vlad the ka-50 instructor won't smack your knuckles for using a different trimming method. :)

Just so you know

The Unchain Rudder from trimmer mod breaks central position trimmer method, I had this problem and fixed it but reverting to the origonal Lua files. The mod was included by accident in NVG RC3 mod so if you have either of these mods then I would guess they are the culprit.

See my forum Posts

http://forums.eagle.ru/showthread.php?t=95390

http://forums.eagle.ru/showpost.php?p=1576841&postcount=223