New Flybarless System

[hamslice]

What happened? Did it just tip over on lift off, or was it a crash after you were airborne?

i think it was a programming error on my part. went to the lhs and got the parts to get her back up in the air tommorrow. i am pretty bummed, because i was so pumped to get her in the air without a flybar. oh well i am sure with some questions answered i will have her flying like a champ.

[hamslice]

skookum,

i will def put 100% on hiller decay next time.

[eurylokhos]

I got mine installed and setup about 30 minutes ago. I'm testing it on a Blade 400 since it's cheap and I have it. The conversion was simple, as were all the connections to the sk360. I can definitely see where people could mess up the setup and kill a heli. The first time I set it up I thought it was all good from following the instructions, but a bit of inattention on my part meant that I missed the need to click the rotate 90deg button in the software. This resulted in the gyro correcting pitch with aileron, and vice versa. Didn't show up in setup unless I really paid attention to what each box said, since moving the sticks resulted in the correct movements of the swash, but getting out of setup mode showed the automatic corrections were wrong. It was pretty subtle, as well, the corrections are not large, and the first couple times i checked it I thought it was correct.

I can definitely see how someone could kill their heli with a wrong click in the software, it's like having your gyro reversed, except instead of spinning it'll drive itself into the ground if you don't get it right the first time.

[SpeedVision]

Success!!!!!!!!!!!:thumbup:

Well I ran 4 batteries the evening in my Mini Titan and everything went very well. Heli is much more quiet... Setup needs help, but that's workable.

Of course, I had the Hillier decay at 25% which did make takeoff's a challenge. Batteries tomorrow will be run at Skookum's suggested setting of 100%.

Now that I have shared my success, I now will display my ignorance. What's a "locked in" flybarless heli supposed to feel like??? If felt way different than I anticipated. Every control input had to be offset to get back to a hover. For some reason I anticipated that inputs would be nulified when the stick was returned to zero. Also, it seemed to want to wander around requiring lots of corrections. I turned hillier gain up, but got oscillation. Ended up leaving it at 52% hillier and 32% bell. Like I said, setup needs help...

Here's what I anticipated: Right elevator and return stick to zero and the heli would return to a stationary hover...

Here's what happens instead: Right elevator and she just keeps going right until I give it left rudder to offset... Could this be related to hillier decay set to 25%???

Finally, I think we need more information on the relationship between elevator and aleron gains for Hillier, Bell and Dampening. The default numbers don't really correlate to the explanations in the manual. Is aleron gain supposed to be 50% of elevator??? Hillier elevator is 50% and aleron is 40%. Bell is 32% and 32%. Dampening is something like 22% for elevator and 19% for aleron. Ratios are all over the place and I just don't understand.....

Sorry for so many in depth topics, but we better air them out now, because I doubt I will be alone. Also, keep in mind that I actually flew 4 batteries without crashing!!! Gotta give me credit for that!!

PS - I have about .6mm of space between the SK and the sides of the frame of the Mini T. I folded a business card over the top of the SK to act as a spacer between the frame. Once the unit was in and stuck down, I removed the card and Waaalaaa, perfectly centered eith a nat's nut hair on each side... Phew...

[SpeedVision]

Ok, so the Skookum website FAQ answered one on my mis-perceptions...


Quote:
What will a helicopter converted to flybarless with the SK360 fly like?

The gyro provides solid "neutral" stability in the pitch and roll axes (aileron and elevator).
This means that if you let go of the sticks, it will hold to whatever attitude it is currently at. If you put it in a perfectly level hover, it should stay there hands-off for some time, even in wind. If you're in forward flight, it will stay in forward flight with no tendency to pitch up or down.

Note that it will not level your helicopter out for you. The control feel is similar to a "heading hold" tail gyro, but applied to pitch and roll as well.

[Wazzer]

Is there any way the SK360 can be set up to provide that self centering effect?

Is it possibel for the unit to be setup in rate mode instead of HH? not sure if thats what would be required.

I guess what im looking for is a form of Stabilty control that would allow the heli to return to center after a control was released.

Cheers

Ben

[fireup]

Is there any way the SK360 can be set up to provide that self centering effect?

Is it possibel for the unit to be setup in rate mode instead of HH? not sure if thats what would be required.

I guess what im looking for is a form of Stabilty control that would allow the heli to return to center after a control was released.

Cheers

Ben

I don't think so. The gyro sensor used is not accurate enough to get an absolute horizontal reading. It drifts a little and so the horizon will change over time.

For that type of application, you have to look into the AP2000i unit that uses light sensors or the helicommand that uses CCD camera sensor.

[MrMel]

an note for all new flybarless fliers,

Low headspeed does NOT equal slower cyclic as you have been used to before, it will be just as fast as full headspeed, for trial flight you need to lower the rollrate/fliprate by other means (in the program, or ATV in radio)

[Wazzer]

I don't think so. The gyro sensor used is not accurate enough to get an absolute horizontal reading. It drifts a little and so the horizon will change over time.

For that type of application, you have to look into the AP2000i unit that uses light sensors or the helicommand that uses CCD camera sensor.

Thanks for the reply

I'm not looking for absolute stability for hands free hovering like the AP guys would be, just some stability aid.
In its current set up using HH type gyros it seems that every input has to be taken out to bring the heli back to level. I was hoping that maybe with some electronic smoke and mirrors the decay rate or something could be adjusted to get it to come back faster than 1 second or so. Maybe its not possible without those additional horizon sensors you mentioned.

My main interest in flybar set ups is for Scale multi blade reasons and appearances more than the increased cyclic responses that will benefit the 3D'ers

Thanks for the pointers

Ben

[Skaross]

As some of you know, we've been asked to test the gyro for a potential problem from cold. The instructions said place the gyro in your freezer for 15 mins... do you think we were supposed to take it off the heli first :)

In all seriousness, this photo was taken for a laugh... if I was doing it for real, I'd have taken the blades off!!! :)

Kev

[kgfly]

Looks like a cool setup to me ;)

[JC]

Looks like a cool setup to me ;):lolol

[fireup]

Nice sword fish you caught there, making sure it don't go bad ha?:)

[Skaross]

Nice sword fish you caught there, making sure it don't go bad ha?:)
It fought hard as we tried to push it in there - something about not liking frozen peas I think I heard :)

[mjr_larkin]

I just got the SK and the usb driver isn't working.

I installed the drivers but now I have that pesky yellow exclamation mark next to the device "COM3":

Windows cannot determine the settings for this device. Consult the documentation that came with this device and use the Resource tab to set the configuration. (Code 34)

If I try to launch the config program (from the email) it says it can't find the usb device.

Any suggestions?

I'm running Vista x64 SP1. Just to note, the spartan usb drivers work fine.

[Skookum]

lbcynya: Congrats on getting your mini titan to fly! The behavior in flight that you describe is correct, except for the wandering.

If it's wandering, there is either too much friction or slop in your rotor head linkages/swash, or the gain is not high enough. You've said you can't put the gain any higher without oscillation, you may be limited by mechanics or analog servos. But I also wonder if the "Advanced" gains could be improved, if you email your setup file to tech @ skookumrobotics.com I can check it over.

Wazzer:

>Is there any way the SK360 can be set up to provide that self centering effect?

No, it would require a 6-axis sensor and heavy math, whereas the SK360 has a 2-axis sensor. There are products that uses visual solutions to self-level, but that would have the obvious limitations. One thing that I'd like to try when there's time would be to chain a low-cost IR horizon sensor with the SK360, that would provide the flying qualities you're looking for with off the shelf parts.

>Is it possible for the unit to be setup in rate mode instead of HH? not sure if thats what would be required.

The unit is effectively a rate-command controller that can work with helicopter cyclic physics, to replace the flybar. That means at centre stick, you should get zero rates (fixed in pitch and roll), and the further you move the cyclic stick, the faster the roll or pitch rate. So when you let go of the stick, it will try to freeze at the attitude you left it.

The main difference from a mechanical flybar is that it can be more rigid, especially in wind. But that also means it has no tendency to resist forward motion, which is the primary handling difference. If you put it into forward flight, it will stay there.

[hamslice]

What happened?

Damage doesn't look to bad (tail boom?).

Look at the bright side - didn't even bend the flybar! :P

it didnt look bad? $236 later and she is back to flying condition. i am just waiting on some questions to be answered before i try again. yeah it was funny the lhs owner said "you need a flybar dont you" i laughed and said nope.

[Ecklund1]

As some of you know, we've been asked to test the gyro for a potential problem from cold. The instructions said place the gyro in your freezer for 15 mins... do you think we were supposed to take it off the heli first :)

In all seriousness, this photo was taken for a laugh... if I was doing it for real, I'd have taken the blades off!!! :)

Kev

You forgot slam the lid down...:banana

[Danish Heliflyer]

I have some issues with my SK360. When i did the test described from support today, i saw under Gyro Internals ( BellDial ) flichers from the amount procent to zero procent. When touching the Bell dial on the SK360 the set amount comes back on the setup menu. It looks like there is some bad welding at the Bell dial.
Could that perhaps led to a full roll or elev during lift off ?

It will be a god ide to to tjek that issue with your own SK360

I will contact support so thay can send me a new one...

Cheers

[hamslice]

well guys i flew it three times no incidents!!!!! i have some minor tweaking to do and i think i will really like this flybarless thing.

[WhirlingBladesOfDeath]

well guys i flew it three times no incidents!!!!! i have some minor tweaking to do and i think i will really like this flybarless thing.
So what was the programming mistake that caused the initial crash (so I don't do the same thing!) Was it just setting the Hiller to 100%? Glad to hear it's working now!

Thanks,
Jason

[hamslice]

So what was the programming mistake that caused the initial crash (so I don't do the same thing!) Was it just setting the Hiller to 100%? Glad to hear it's working now!

Thanks,
Jason

well i had the pilot control inputs backwards and did not catch it. so when i tilted the heli the swash would follow instead of counter the movements. i then thought because of this that if i just flip the ail and elev axis it would work (thought i had a mounting issue). it seemed to have worked because when i would test the swash reaction it would counter. needless to say it didnt and i crashed before the heli even left the ground. after art and i figured out what i had wrong the heli is flying pretty good now.

[hamslice]

i dont really know if the hiller decay helped or not yet as i have not changed it from anything lower than 100% to see how it effects the heli in flight.

[chichisport]

Is there any revision of the instructions that cover those aspects.

I did not catch the decay thing yet , it will be good to have a deeper explanations of its purpose . for me now it seems like a damper to soften the stopping but did not catch the memory effect when spooling .

Juan.

[Skookum]

Danish Heliflyer>It looks like there is some bad welding at the Bell dial. Could that perhaps led to a full roll or elev during lift off ?

Sounds like a bad solder joint yes. But no, it wouldn't cause roll or elev at take off. And it wouldn't lead to problems if it happened in flight, because the gyro only reads the dials at startup and when it's sure that it's on the ground.

I've emailed DF, and will be sending out a replacement.