Airbrakes on an Optic6?

[Tim Hooper]

Gents,

I'm having a small problem setting up airbrakes on an Optic6/Optima6 combo.

The model in question is an RET Bird of Time, so there are no ailerons to worry about. I'm flying Mode2 so the rudder will be controlled by the r/h stick on channel 1.

I'm fitting airbrakes to the inboard panels, and so I can adjust their throws and endpoints individually I want to set them up on seperate channels mixed together. I also need to have one of the channels reversed to suit the servo installation.

I'm wanting to have the brakes controlled by the left lever on channel 6, and to disable the right lever so that it can't be moved inadvertantly.

The model memory has been reset to factory defaults prior to programming.

To operate the second airbrake I've activated P-Mix1, and am using channel 5 as a slave.

My problem is that although I can get both servo servos to operate in sort of unison (with the appropriate end-points), I can't get the slave (channel 5) to operate linearly. Both servos start together, then the slave lags behind in the mid-range of the throw, then speeds up again to catch up with the master at the end of the channel.

It's almost as if there's a good dollop of expo built in to channel 5. It's not the servos at fault; I've tried it with servos of a different manufacture and the result is the same.

I'm sure there's either a quick fix, or another way of achieving this. Can you help at all please?

tim

[Biggles' Elder Brother - Moderator]

Tim,

 

on my 8FG there is a "flag" at the bottom of the P-mix screen called "Linear" - this is the default setting, it can be changed to a non-linear setting (though I've never done it! Is it possible that you have inadvertantly toggled some equivalent of this on the Optic on the slave channel?

 

BEB

Edited By Biggles' Elder Brother on 06/07/2010 09:51:08

[Bob Cotsford]

Try this - set PMIX2 to mix ch5 with itself at -100%.  I just tried it on the bench, and I found one servo would be non-linear depending on the gear switch position  without this.  Mixing Gear with itself to give zero movement on the switch seemed to match the movement.

As the Optic is my reserve tx, I'm not that familiar with it so there is probably a better way somewhere in the options.

Edited By Bob Cotsford on 06/07/2010 11:50:56

[Tim Hooper]

BEB,  Your tx is obviously far fancier than mine, but thanks for the suggestion anyway!

 

Bob,  adding PMIX2 as you suggested has certainly cured the non-llnearity of the servo response  - thank you very much!

 

Now I need to disbale all the switches - all of which seem able to move at least one of the servos in varying directions!

 

tim

[Bob Cotsford]

buy an FF9, Eclipse or Aurora?  I think this is one of the limitations of the Optic, it decides what is assigned to any particular switch, and it's designed tor two or three servo wings, there's just not enough channels for 4.  It's a nice budget transmitter, better in may ways than the Futaba FF6, but it is a pretty basic computer radio, as I came to realise when comparing it to an FF8.   A clubmate had just bought an Aurora, that is IMHO the next step in interfaces and usability.  All the same, I bet there are still functions it can't do easily.

 

Now, if anyone can come up with an Optic setup for a 4 servo wing that gives:

CROW

Ail > Flap mix

Flap > Ail mix (proportional, not switched, camber change)

I will be eternally grateful (and absolutely amazed)

Edited By Bob Cotsford on 07/07/2010 12:30:46

Edited By Bob Cotsford on 07/07/2010 12:32:04

[Tim Hooper]

Thanks Bob.

 

I've managed to disable all but two of the sliders and switches, so we'll leave it at that for the time being!

 

As you say, the Optic is probably punching above its weight in this application - although it features a crow  and variable camber setups in its programs, there's certainly no facility for using more than one flap serve (unless to rig them onto the Y-lead and sort out the relatives throws mechanically).

 

 

tim

 

 

[Bob Cotsford]

Tim, as I found out, the variable camber is more in the way of flight modes set up on the 3 position switch, and both that and crow are only for 3 function wings, ie single flap or twin flap with Y lead.  I was going to transfer my Cularis on to it, but I'd lose the propo camber change and mixed flaps with ailerons,  which is really needed to aerobat the Cularis.

 

The Optic's still perfectly good enough for a slope or power sport aerobatic model though!

 

Bob

Edited By Bob Cotsford on 08/07/2010 09:35:27