Go Back  RCU Forums > RC Airplanes > RC Jets
Reload this Page >

Futaba Flight Condition question

Notices
RC Jets Discuss RC jets in this forum plus rc turbines and ducted fan power systems

Futaba Flight Condition question

Old 08-15-2014, 07:03 AM
  #26  
Dieselman1220
Thread Starter
My Feedback: (25)
 
Dieselman1220's Avatar
 
Join Date: Feb 2004
Location: McAllen, TX
Posts: 814
Likes: 0
Received 0 Likes on 0 Posts
Default

Bob on the 12fg it's the same screen you showed me above. Condition delay under the flight conditions menu. While the servo is
transitioning from one condition to the next, and you move the stick while its moving the servo will only move at the speed you have selected until the transition is complete. For me it's not a big deal. But for example if you required a large and slow control serface change
between flight modes it could get you in trouble.
Old 08-15-2014, 07:25 AM
  #27  
Bob_B
My Feedback: (11)
 
Bob_B's Avatar
 
Join Date: Nov 2003
Location: Bluegrass State of Mind
Posts: 4,074
Received 1 Like on 1 Post
Default

Interesting I have never noticed this.
Old 08-15-2014, 08:41 AM
  #28  
mauryr
 
Join Date: Dec 2010
Location: , ITALY
Posts: 482
Likes: 0
Received 0 Likes on 0 Posts
Default

I set this up for a test on a feibao velox XL which requires much up elevator with landing flaps. I really wanted to slow down the deployment of the offset, but I am basically unable to move the elevator during the flaps deployment and that truly scares the hell out of me
Old 08-15-2014, 08:45 AM
  #29  
Bob_B
My Feedback: (11)
 
Bob_B's Avatar
 
Join Date: Nov 2003
Location: Bluegrass State of Mind
Posts: 4,074
Received 1 Like on 1 Post
Default

I understand, you can still use the separate trims without delay, I would think slowing would avoid the jump. Or deploying the flaps during a turn in the pattern where you are holding a fair amount of up elevator would work.
Old 08-15-2014, 08:49 AM
  #30  
Dieselman1220
Thread Starter
My Feedback: (25)
 
Dieselman1220's Avatar
 
Join Date: Feb 2004
Location: McAllen, TX
Posts: 814
Likes: 0
Received 0 Likes on 0 Posts
Default

Mauryr speed your flaps up a little bit, then you can speed up your elevator. My bobcat requires about a quarter inch of up with full flaps.
I'm around 20 on my flap and elevator speeds. The transition is so smooth I don't even need to touch the elevator during configuration changes.
Old 08-15-2014, 08:54 AM
  #31  
mauryr
 
Join Date: Dec 2010
Location: , ITALY
Posts: 482
Likes: 0
Received 0 Likes on 0 Posts
Default

Right now, what I do is slow down quite a bit and give a little down elevator as soon as I hit the flaps switch, but the jump up is quite noticeable because the elevator corrects right away while the flaps are not deployed yet.
It would be really nice if a firmware update would fix this.

It's really simple... right now:
final_pos=servo_pos+(gimbal_pos-servo_pos+newoffset_pos)*slow_k
should become:
final_pos=gimbal_pos+newoffset*slow_k

Essentially... take the delta position between current servo pos and requested gimbal pos out of the slowing multiplier coefficient, which should just act on the offset

Any way to get it through to futaba?
Old 08-15-2014, 08:55 AM
  #32  
mauryr
 
Join Date: Dec 2010
Location: , ITALY
Posts: 482
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by Dieselman1220 View Post
Mauryr speed your flaps up a little bit, then you can speed up your elevator. My bobcat requires about a quarter inch of up with full flaps.
I'm around 20 on my flap and elevator speeds. The transition is so smooth I don't even need to touch the elevator during configuration changes.
That would work, but a cure to the disease would be better
Old 08-15-2014, 09:01 AM
  #33  
Dieselman1220
Thread Starter
My Feedback: (25)
 
Dieselman1220's Avatar
 
Join Date: Feb 2004
Location: McAllen, TX
Posts: 814
Likes: 0
Received 0 Likes on 0 Posts
Default

I agree with you Mauryr, it's not right, but I can live with it. If a fix were to become available I would definitely do it.
Old 08-15-2014, 09:03 AM
  #34  
Bob_B
My Feedback: (11)
 
Bob_B's Avatar
 
Join Date: Nov 2003
Location: Bluegrass State of Mind
Posts: 4,074
Received 1 Like on 1 Post
Default

Originally Posted by mauryr View Post
That would work, but a cure to the disease would be better

I will ask ask about this issue.
Old 08-15-2014, 10:09 AM
  #35  
Geoff White
 
Geoff White's Avatar
 
Join Date: May 2002
Location: Oxford, UNITED KINGDOM
Posts: 1,151
Likes: 0
Received 0 Likes on 0 Posts
Default

Hi Bob,

A few years ago I showed a friend how to use flight conditions and condition delay on his 18mz. He went away and started playing with this. A few days later he phoned me up and told me of the issue with the servo responding slow. At first I didn't believe him as I had been using condition delay for a long time(mainly on flaps/elevator) and never felt the slow response during flight. Of course, he was right and the 'feature' does exist.

I contacted futaba support(RCU forum) and asked them if this was correct. They said it is working as designed and there were no plans to change it.

From my experience I don't think its a major problem as I can only detect the slowness if I really 'pump' the elevator rapidly, which of course you don't do in flight. Added to the fact that I still use condition delay to this day.

It will be interesting to see if Futaba still say its not an issue.
Geoff.
Old 08-15-2014, 10:23 AM
  #36  
Bob_B
My Feedback: (11)
 
Bob_B's Avatar
 
Join Date: Nov 2003
Location: Bluegrass State of Mind
Posts: 4,074
Received 1 Like on 1 Post
Default

I have been giving this some thought, not being an electronics expert, but since we have delayed the servo speed when moving to a new trim position it would only make sense that any other inputs to that channel IE: a stick input would see the same delay during that brief time period. To be honest I've never noticed this delay during flight, but will have a look tonight in a static condition. I wonder if this is common to all radio brands when you use a similar feature/setup.
I've posed the question, so lets see what they have to say.
Old 08-15-2014, 11:14 AM
  #37  
mauryr
 
Join Date: Dec 2010
Location: , ITALY
Posts: 482
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by Bob_B View Post
I have been giving this some thought, not being an electronics expert, but since we have delayed the servo speed when moving to a new trim position it would only make sense that any other inputs to that channel IE: a stick input would see the same delay during that brief time period. To be honest I've never noticed this delay during flight, but will have a look tonight in a static condition. I wonder if this is common to all radio brands when you use a similar feature/setup.
I've posed the question, so lets see what they have to say.
Bob, the servo goes wherever the radio tells it to go.
It's all in the software and, as a programmer by trade, my opinion is the programmer simply took the easy way out, not deeming it important to take the extra 10 minutes to do it properly.
What they did is simply to set a servo slow right before inputting the new destination coordinate to the channel position, to remove it after a given amount of time.
What they should have done is calculate the delta between the precedent condition's trim and the new one and then feed this delta into the channel over time.

As it is now, you can see that if you give an input to the channel in the opposite direction of the trim adjustment movement, it will move in the direction of the input, but very slowly.

Imagine what would happen if you had the trim adjustment slow set up onto the aileron and you needed to suddenly compensate for an unexpected asymmetric deployment of the flaps for example...
Old 08-15-2014, 11:37 AM
  #38  
Bob_B
My Feedback: (11)
 
Bob_B's Avatar
 
Join Date: Nov 2003
Location: Bluegrass State of Mind
Posts: 4,074
Received 1 Like on 1 Post
Default

Mauryr, I get it! I do understand that the servo only moves to the position the radio commands it, to move to. I can tell that this issue really concerns you.
Can I quote you on what you believe would fix this issue?
Bob
Old 08-15-2014, 01:42 PM
  #39  
mauryr
 
Join Date: Dec 2010
Location: , ITALY
Posts: 482
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by Bob_B View Post
Mauryr, I get it! I do understand that the servo only moves to the position the radio commands it, to move to. I can tell that this issue really concerns you.
Can I quote you on what you believe would fix this issue?
Bob
Sure

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.