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Old Oct 20, 2011, 04:36 PM
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Originally Posted by foam and tape View Post
ok, I'll try this later today, i'm currently using the DX7. What kind of servos did you use Leadfeather on your F-35?
I'm using a DX7 also. I've got HXT900's for the control surfaces and a 12 gram metal gear servo for each tilt servo.
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Old Oct 22, 2011, 05:43 PM
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Ok, forward flight with rcvertt's rudder gyro mix was pretty good! untill the whole air frame locked out and it just had the most spectacular crash ever. It was going ok, the gyros in FF have their gains too high. I'm still not sure how it locked out like that? No motor response, servos idled and the whole thing just rolled over to the left slowly and augured in at a 80/90 degree angle. scratch airframe II. LOL I just taped it up and hotglue'd it together real quick for another test. I'm thinking BEC failure on that run? or the gyros were working too hard?

RCvertt, is it possible to write the code without gyro enabled FF rudder. It wasen't too necessary for flight as it had a little too much control in some turns, and a little bit of expo would be cool too, the stick movements were too high.
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Old Oct 23, 2011, 12:50 AM
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Ok, forward flight with rcvertt's rudder gyro mix was pretty good! until the whole air frame locked out and it just had the most spectacular crash ever...
Sounds like progress. If you're using a turnigy 3amp switching BEC, make sure that a line from it feeds into both your receiver and your ProMini. If your receiver or servos are sucking power from the ProMini, it would definately cause a brown out. If your spectrum receiver was blinking after the crash then you definitely had a brown out. If your using a built in BEC from an ESC, those things usually aren't powerful enough to handle a VTOL set up. Working the gyros hard could cause a brown out if there is a weak spot in the wiring set up.

Connect your ProMini to the configurator and let it run for about 10 minutes to make sure the sensors don't freak out on their own. I had a gyro board go bad on me once where the gyro numbers would go to full deflection after 5 minutes of letting it sit for no apparent reason.


Quote:
Originally Posted by foam and tape View Post
...RCvertt, is it possible to write the code without gyro enabled FF rudder. It wasen't too necessary for flight as it had a little too much control in some turns, and a little bit of expo would be cool too, the stick movements were too high.
Yaw gyro control for FF is completely removed in the attached file.


For expo you can use your TX expo for the yaw channel. You can remove your props, arm your quad and look at the configurator motor command chart to visually see what affect your expo amount is having on the motor commands as you move the sticks. I fly with about 35 percent on my DX7.

If you want to limit the total amount of yaw that is available, you can use your DX7 endpoint adjustment for the yaw channel. Move your trim tab all the way to the right so you can arm your quad but don't forget to move it back before flying.
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Last edited by RCvertt; Oct 23, 2011 at 02:05 AM.
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Old Oct 25, 2011, 05:03 PM
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well scratch airframe II, I don't even know how to describe its last flight

So after realizing that this design is breaking the laws of physics and not letting it work, I've come up with this new QTR! I'm hoping hover performance will be even better as the motors are now equidistant from each other. Also hoping that the more conventional canard look of it will translate into more predictable flight performance. Anyone know where the CG may possibly lie? I'm hoping that it'll balance in the middle of the quad.

oh and this is the first air frame! I just recycled it by ripping off the old wings in the most crude manner possible!
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Old Oct 25, 2011, 05:53 PM
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well scratch airframe II, I don't even know how to describe its last flight

So after realizing that this design is breaking the laws of physics and not letting it work, I've come up with this new QTR! I'm hoping hover performance will be even better as the motors are now equidistant from each other. Also hoping that the more conventional canard look of it will translate into more predictable flight performance. Anyone know where the CG may possibly lie? I'm hoping that it'll balance in the middle of the quad.

oh and this is the first air frame! I just recycled it by ripping off the old wings in the most crude manner possible!
You RC room is almost as messy as mine!

To get the cg close enough for a first flight I do it like this:

Calculate the relative wing areas; ex front wing is 25% rear wing is 75% of total.

Guestimate the cg of each wing independently.

Determine the distance between these two cg's

Place the overall cg at 25% (for this example) ahead of the main wing, + a little further forward to be safe and have the front wing stall first.

Hopefully this will get you close enough for a test flight and cg tuning without a crash.
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Old Oct 25, 2011, 06:21 PM
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Some where on the net is a formula in a spread sheet forum to figure that ... you just fill in the blanks of your craft ... but I don't have time to find it ... Leads way is probably the quickest .
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Old Oct 25, 2011, 11:36 PM
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You RC room is almost as messy as mine! ...
Looks like mine after I've cleaned it. His picture is missing about two feet of foam shavings

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Originally Posted by foam and tape View Post
...I've come up with this new QTR!...
Looks more stealthy which is cool. I like that canard/F35 thing you have in the back ground also.

I use this canard calculator and place the cg about an inch in front of what ever it tells me.
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Old Oct 25, 2011, 11:46 PM
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here's some vid, hahaha the foam shavings are piling up against the walls form all the prop wash

I have no use for a vacuum cleaner.....

QTR VTOL II hover testing (1 min 2 sec)
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Old Oct 25, 2011, 11:54 PM
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here's some vid, hahaha the foam shavings are piling up against the walls form all the prop wash

I have no use for a vacuum cleaner.....
If Hoover made these, I would buy it. Looks nice and stable.
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Old Oct 26, 2011, 12:00 AM
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If Hoover made these, I would buy it. Looks nice and stable.
peferebly it dosent suck* (pun intended ) in forward flight!
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Old Oct 26, 2011, 01:34 AM
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Just noticed your rear pod vanes idea and how it blends into the wing, very nice.

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peferebly it dosent suck* (pun intended ) in forward flight!

As they say, when in doubt, make the rudder and elevons twice as big
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Old Oct 26, 2011, 06:08 AM
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here's some vid, hahaha the foam shavings are piling up against the walls form all the prop wash

I have no use for a vacuum cleaner.....

http://www.youtube.com/watch?v=PcriIS1EFIg
I'm sure I saw this scene in a movie. A future apocalyptic world in ruins; humans running from the terminators.... except the hunter killer craft weren't pink.

Very nice hovering. Congratulations!
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Old Oct 26, 2011, 06:55 AM
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Looking good F&T hope it performs in forward flight too .
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Old Oct 26, 2011, 07:50 AM
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nice work
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Old Oct 27, 2011, 06:09 AM
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F&T, One more thought on cg; if you leave the gyros enabled on the control surfaces in forward flight it will make the craft more stable even if it is tail heavy. Early on in the development of my F-35 I thought I had the fixed wing cg spot on. Then, for fun, I turned the control surface gyros off...not so fun, I could barely fly the jet and was lucky to get it back down with out crashing. It was really tail heavy but I had never noticed previously because the gyros had compensated.
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