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Strange flap movement

help needed

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J V R21/04/2014 18:49:59
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I have a couple of planes set up with either flaps or flaperons on a 3 position switch and I keep getting a strange movement or a bounce at the bottom of the flap movement. Is it me when I make the mix on CX9 or do I have a problem with my Taranis. I have uploaded a couple of videos to the Bucket and if I have done the correct linking you will see the bounce at the end of the stroke

**LINK**

Bob Cotsford21/04/2014 20:44:53
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I can't see the video but I have experienced bounce or overshooting with some brands of servo when moving them fast - as in flicking a stick which is similar to using a switch. If I move the stick at normal rate they follow the movement smoothly, so I would suggest slowing down the servo action even if only by 0.2 second and see if that fixes the problem.


Biggles' Elder Brother - Moderator21/04/2014 21:02:30
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Wow! That's amazing. I take it the actual model does it as well - not just C9X?

I can see a little bit of your mixer programming behind the Tx simulation. One thing I would say - and I'm not saying this is the problem but I have had a few strange things happen when doing this - be very careful about whether you specify an input as a channel rather than a stick. So using CH4 as the input to a second aileron channel works fine 99% of the time - but under some circumstances, like if you are using differential, it really screws up! You need to use AIL as the input in the CH5 mix.

Now as I say whether this is part of your problem I don't know TBH - but it might be worth straightening out first to see if the effect is still there.

BEB

J V R21/04/2014 21:36:41
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Hi bob

Hopefully this idea from Pete B will work & you will see the video.

BEB I will post the mix shortly, at the moment I have multiple windows open on my PC trying to embed one of the video's that I have on Photo Bucket

Edited By Pete B - Moderator on 21/04/2014 23:01:35

J V R21/04/2014 21:42:28
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imag0580.jpg

J V R21/04/2014 21:44:53
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One of the short video's of the flaperons

 

Edited By Pete B - Moderator on 21/04/2014 23:02:57

Biggles' Elder Brother - Moderator21/04/2014 21:56:03
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JVR, I'll PM you an email address, can you send a copy of the eeep file? Then I can have a look - no promises but the problem looks interesting!

BEB

Biggles' Elder Brother - Moderator21/04/2014 22:54:29
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OK got the file - which model should I look at?

BEB

PS OK Prankster - amazing mine does the same - I'll have a look around

Edited By Biggles' Elder Brother - Moderator on 21/04/2014 22:56:52

J V R21/04/2014 23:06:36
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BEB

I followed one of Scott page's videos on the other '' forum'' and got an even more exaggerated effect on the elv using a slider to control the down mix to compensate the lift made by the flaperons so I deleted that one and put the elv mix on a switch

Jan............

Biggles' Elder Brother - Moderator21/04/2014 23:07:57
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Well the first thing I've noticed is that if you change all the delays to 1 sec - up and down on both settings of the flaps and the effect goes away.

BEB

J V R21/04/2014 23:14:15
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Thats good news BEB, I used a long delay to lessen the effect of extra lift caused by the flaps

Jan...........

Biggles' Elder Brother - Moderator21/04/2014 23:14:45
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OK it happens when ever the down slowing is more than the up slowing no matter by how much.

Its also bigger the bigger the slowing

It only effects the second step - never the first

Off to try some other stuff

BEB

J V R21/04/2014 23:17:07
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Yes that's correct with my fun cub, its the second stage that behaves badly

Biggles' Elder Brother - Moderator21/04/2014 23:17:22
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Oh - if you make the up slower than the down - the bounce happens at the start of the movement - not the end!

BEB

Biggles' Elder Brother - Moderator21/04/2014 23:20:36
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It still happens if you delete the down elevator mix so its not that

BEB

Biggles' Elder Brother - Moderator21/04/2014 23:23:57
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Ah - if you delete the intermediate step - so you just have full flaps down with SB down - it doesn't happen. Let's see what happens if we have three steps instead of two...

BEB

J V R21/04/2014 23:24:58
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Strange..........

Biggles' Elder Brother - Moderator21/04/2014 23:30:48
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OK - putting a third flap stage on SC- set to 60 - it didn't show the bounce at the third stage - but its still there at the second stage.

Putting stage one flaps on SB- then stage two on SC- and no bounce on either smile

So it only happens when the down and the up slowing are different and the multi-stages are on one switch. Otherwise it doesn't happen

BEB

J V R21/04/2014 23:39:37
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So is it a fault with the transmitter ? or a bug that needs sorting out ?. I would have thought that if you have switches with multi positions & the ability to slow up and down movements you should be able to do it from one switch. Thanks for the work you are doing BEB.

Biggles' Elder Brother - Moderator21/04/2014 23:43:41
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OK - a bit of a breakthrough. If you make the first stage movement have the same speed up and down, then even with the second stage having different speeds it works fine.

What you can't do, without getting the "wiggle", is have the first stage at different up and down speeds - unless you put them on separate switches! I don't know why! That's a job for tomorrow!

If first and second stages have the same up and down speed again no wiggle

I have emailed an altered eeep file back that doesn't show the effect - that's done by setting the first stage flaps to the same up and down speed. Hope that at least helps for now!

BEB

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