600 My swash wont remain straight through the travel

[coolgabsi]

??????


Why??

When I start the video the swash is too low on the far side and when I move it up, it will be the one highest.. Seems like on that one servo arm I have more travel than the others

This is a 140Defree JR setup with ikon fbl.

Please help
Swash setup issue .... - YouTube

 

[Tony]

Okay, stupid question, you are using the exact same servos all the way around right? Those look like Align DS610's to me.

The arm on the servo could have the hole a little farther out than the other two, that would account for this.

Check your travel menu and make sure it's exactly the same as the pitch and elevator.

If all else fails, find a 120º swash and stick on there to see if that cures it, but don't think it would.

 

[pvolcko]

I'm thinking along the same lines as Tony. Make sure you are using the same holes on the bellcrank arms and servo horns (and pull out the calipers to make sure the distances from pivots are in fact the same, maybe have a mismatched set of horns or bellcranks or some kind of manufacturing defect in one of them). Make sure the two swash ball arms on the swash are the same length. Unlikely, but make sure you do not have a pitch->ail mix in the Tx.

Ikon... There's no servo travel/range type adjustments in there that I know of. Maybe check advanced mode to make sure all cyclic servos have the same settings (don't recall if they break them out individually in there or not). If there are per servo adjustments available in advanced mode, and mechanical setup checks out, maybe try adjusting that servo pulse width or travel range.

Another option is to ignore it. If it is flat at 0 degrees/neutral and even difference on the max pos and neg positions, then fly it and see what happens. The FBL may well automatically counter any ail roll it induces since it would interpret it as undirected error (same as wind or other external error sources) and attempt to neutralize it.

 

[Lee]

Did it just start doing that or have you changed something?
Can you adjust the travel limits on that one servo to get it level with the others?

 

[coolgabsi]

I just never caught it. Been flying like this for a while... Noticed my swash would be tilted forward at boot up at negative pitch.

Centered all as at zero apparently had a little adjustment to be made and re initialized at negative pitch and same problem.. Then started digging

It makes a difference as going from stationery to hover, heli wants to move forward like it needs to be trimmed back

And at climbs the heli goes nose up

Stupid

I am going to inspect that bell crank today

 

[coolgabsi]

I found out there is a servo wise "Positive throw" and negative throw adjustment on the IKON software under COmmon>servos.. Hey I might be learning something new if this gets figured out!!! I am excited


I am going to start with my bell crank like y'all said, then go to the servo horn and then , I am thinking, I bought these servos used, If by chance someone had the bright Idea to mix and match servo gears, the throws could be different.

NEVER know what that could be. I never caught this before cause I never had a swash levelling tool and this difference was so little that it is not noticeable unti lin flight.

So now that I found a swash leveller for my bird, I discover this. Good to have the right tools to do setup. haha

 

[Tony]

Gears won't make any difference. Everything is run off of the pot in the servo. As I posted, if your throws are 100% in your Tx as they should be, then it has to be somethign mechanical. But, if you can dial this out in the Ikon, great. I am pretty sure people can do the same thing with the AR7200BX as well. Post up some video of making these changes.

 

[pvolcko]

As far as I know there is no way to do individual servo throw adjustments on the 7200BX. There is individual centering for swash neutral setup, but that's it. Unless there is some option when using a USB connection and software. I'd be surprised if there is.

 

[Tony]

YOu can see how long it's been since I played with a 7200 lmao. I set that thing up one time, and it was solid as a rock, so I didn't mess with it. I know, it's not me, but it was on an expensive helicopter that I really don't want to crash lmao. i will however be playing with this gyro on the 450. Just sucks that I have to mount it up top with all of those wires showing...

 

[coolgabsi]

There is one on IKON ... IKON programmer replkied, and so did many people.. They said this happens, seldom but happens.. that servo all the same dont react the exact same way

That is why they have that menu that apparently lets you make sure all servos travel the exact same way .. like in this case only one servo is causing the issue, and if I can level that servo equal to the other two, this will be a WIN!

I have honestly never had this before, where three same servos end up having a bit of different travel. but I am seeing many responses of people saying that happens. INTERESTING>


YES tony the pot makes it move, but you can mix and match gears and the end output be dofferent (DOING THAT IS WRONG) .. more or less than stock throw.. I have done that mistake on my MKS servos.

 

[Tony]

No, the pot does NOT make it move, it tells the servo where the output arm is located. You can put whatever gears in there that you want, the pot will always stay the same. But, this is not the topic lmao. And don't get me started on a debate, I'm in a mood

And how do you know it's that one servo that is causing the issue? How do you know it's not the other two just not moving enough? huh? HUH!?!?!?!?!?!

 

[pvolcko]

I agree, doesn't matter what servo gear train is as far as positional accuracy. It will affect torque, speed, perhaps center hold and position hold capability. Gearing can result in slowing it down or speeding it up so much that it may slosh back and forth around a hold point since the PID loop inside these things are tuned for a certain range of gear train behavior.

The pot itself or factory calibration of output to input signal is probably the culprit in this case. I'm kind of surprised this doesn't happen more often, actually. Especially when mixing servos from different production runs or years of production, even if the same model.

 

[coolgabsi]

Ok ok doesn't matter


BTW, I did figure it out and yes I got all three servos straightened out using servos menu in advanced screen. It's amazing what all I can do with this ikon man!!! It's amazing. Made a video with results of the setup.

Still got to equalize the throw but now that in know what to do, i should be able to precisely tune it

Uploading videos

 

[coolgabsi]

Forgot I had uploaded already lol

Ikon servo tubing.. - YouTube

 

[Graham Lawrie]

Very interesting thread.

On my 450 I had a similar problem, swapped the servo to another plug and the problem followed. Turned out it was a small cut in the servo wire.
Glad you found the problem

 

[pvolcko]

Cool. I was thinking there was a menu like that on the Ikon in the advanced section, just had never played with it.