Swash plate does ?

[Cagey]

Simple to some but a bit of a mystery to me, swash plate mixing is set at a default of 60% on my DX6i, with another two mix settings available. Firstly, what is this mixing for, what does it do and why ? Why is there options for other mixes, how many do we need already ? The mixes were set for me at ail 50%, ele 50% and pitch 60%, percentage of what and why change the given value ? I'd be most obliged if someone can explain please.

[pchristy]

This is the mixer that does the ccpm mixing. If you waggle the "elevator" stick forwards and backwards, that would normally only move one servo, whereas with ccpm, you want all three to move! The various percentages govern how much the relevant servos move in response to each stick.

So, if you find the model sluggish on "elevator", altering the elevator mix will increase the response of all three servos to elevator input.

If you try and achieve this with the elevator travel adjust, you will only affect ONE servo - the one plugged into the elevator output on the receiver - which will result in severe trim changes as you waggle that control!

Beware of putting too much input into any given function on the swash mix. Its probably not advisable to go much beyond the default 60%. Otherwise you introduce a lot of non-linearities at extreme throws.

Also, the "expo" function on the swash mix isn't a real "exponential" function. What it does is to try and make the angular movement of the swashplate proportional to stick throw, no matter whether the stick in centred or up one end.

You can also set the mix functions to negative values in order to reverse that function. For example, if everything else was correct, but the elevator function was reversed, setting the swash mix for elevator to -60% would correct this.

Reversing just the elevator channel, would only reverse the one servo plugged into the elevator output from the receiver, leaving the other two still working in the original direction - NOT what you want!

[Cagey]

Swash thingy

Thank you for your speedy reply Pete, I really appreciate it. Yep, that all makes perfect sense to me, I think The tenuous grasp I had wasn't too far out after all. Would I be right in thinking that a reduction in the default of 60% to 50% on ail and elev would be similar to 10% expo on these cyclic inputs ? Or am I assuming too much.

[pchristy]

It would be more like a 20% reduction in the travel adjust. Remember that the swash mix is only 50 or 60%, so knocking 10% off that is like knocking 20% of a 100% travel - er, if that makes any kind of sense!

Basically, 10% on the swash mix is about twice as effective as you might expect!

Do not confuse it with expo, which only affects the sensitivity over a narrow region around center stick. This is so that you can have reasonably tame controls for hovering, but still have maximum control authority when you need it in a hurry!

[Cagey]

swash again

Basically Pete I'd like to say it all makes sense now, but can't, because I'm back to the confused state which seems to be my default setting re helis and swash doodahs. But, thanks loads for trying, it's just your bad luck that this learner's a dunce.

[pchristy]

The thing to do is copy your existing settings to a spare memory, and then experiment with the various settings and see what happens.

Especially experiment with negative percentages, and then try reversing (say) just the elevator channel.

Hopefully this will make it all clear, and you'll still have your original model memory stored safely away!

[ReadyToFly]

i use the swash mix to determine how much travel the servos will have and, mainly, to establish the max and min pitch degrees.

for example, if the mechanical setup is OK and i'm having only 5 degrees of positive pitch, i can increase the pitch value on the swash mix menu so i`ll have 7 or 8 degrees.

as to the aileron and elevator, i can determine the max travel these servos arms will have.

so, the swash mix menu determines the travel potential the cyclic servos will have.

every other feature - like expo and d/r - will work within the boundaries estabilished by the swash mix menu.

i hope i`m not mistaken.

[Nick B]

Hey Ken,come up the field over the weekend and i will try and explain it all to you

[Cagey]

Hey Ken,come up the field over the weekend and i will try and explain it all to you

Will take you up on that Nick, the weather don't look too good tho' and you know me, still in hibernation till the sun puts in an appearance.
Cheers mate, Ken.

[coptermanic]

.............see you in May or June then Ken!!!!!!!!!!!!!!!

[Nick B]

Bleedin fair weather fliers

Its a weird science is swashplate mixing when clueless,Ken

I remember i spent 2 hours on my 500 trying to get it right when i was clueless.....frustrated for the whole saga