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Old Dec 19, 2012, 11:02 AM
I never finish anyth
United States, TX, Houston
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Quote:
Originally Posted by Bill Glover View Post
We could start with RTFM
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Old Dec 19, 2012, 02:13 PM
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United Kingdom, Norwich
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Quote:
Originally Posted by T J Gilbert View Post
Page 14 relates pulse width to throttle position with a formula based on the pulse width output of your particular transmitter.
I don't think it helps your problem.
The irregular start-up seems to just be an annoyance.
(As previously posted by several.)
Always keep your trims at zero.
The reasons why are back in the threads for your searching.
There's some stuff about trims on my blog...
Thanks TJ ...do you mean zero or middle?
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Old Dec 19, 2012, 03:13 PM
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Zero Trim

Quote:
Originally Posted by jetstuff View Post
Thanks TJ ...do you mean zero or middle?
Technically, zero trim is middle on all your stick's trim levers.
Even Throttle is zero = middle on my JR9303H...
Theoretically, you need negative throttle (provided by trim) to make a gas or glow engine cut off. There's no need for that with electric stuff. So, if you choose for zero throttle trim to be all the way down, and you calibrate it that way in the Assistant, that's where it will be. Just remember to leave it where you calibrate it to be zero.
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Last edited by T J Gilbert; Dec 19, 2012 at 04:02 PM. Reason: Explanation & risking saying too much which could = confusion
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Old Dec 19, 2012, 08:49 PM
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United States, WA, Redmond
Joined Dec 2011
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Sooo, I've been wanting to do this since day one of flying the naza, and I'm finally getting around to doing it but I don't want to spend a lot of time on this if its already been done:
The plan is, tie the quad up on strings, mount an accelerometer, and log the accelerometer voltage on my Eagle Tree data logger for a range of gain settings, for each flying mode, with a step input (full stick to neutral or vise versa) so we can finally quantitatively define the gain effects. I could overlay all the graphs to get a good look at the relative effects.

I did step one tonight and the results were very enlightening. I tied up my quad so that it rotates about the roll axis. I programmed the basic roll gains to a slider on my tx and put the attitude gains on a second slider. I spooled up in attitude mode and I found that if the basic gains were too low, it would drift from level, raise it and it would level out. Previously I could never notice the effects of changing the basic gains. The effect of varying the attitude gains were similar, meaning if it was too low it would drift, but the attitude gains had a larger affect on how quickly the quad responded to stick inputs. So, this corresponds with TJ and TE's explanations, but being an engineer I'm not satisfied with qualitative observations. I need data.

So, I have the accelerometer on the way so I could probably knock this out this coming week as I'm on vac, but please let me know if anyone knows of a similar study already done, because its a bit of a project.
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Old Dec 19, 2012, 11:55 PM
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United States, UT
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I got in a flight tonight.

FPV Japan stopped recording, so all I have is this footage.


I was testing a low output IR LED.

I've got some High Output IR LED's on the way.

FPV Hexacopter Night Flight (3 min 26 sec)
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Old Dec 20, 2012, 05:26 AM
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What are you hoping to illuminate with your infrared LED's?
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Old Dec 20, 2012, 06:55 AM
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@Cervanchez

I've not seen any test data on gains like you are proposing to collect.
Thanks for making the effort.
Since you're after hard data, be sure to document your findings.
I'd love to see them added to the beginning of the thread, and I'll gladly post them in my blog...
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Old Dec 20, 2012, 07:48 AM
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United States, WA, Redmond
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Quote:
Originally Posted by T J Gilbert View Post
I've not seen any test data on gains like you are proposing to collect.
Thanks for making the effort.
Since you're after hard data, be sure to document your findings.
I'd love to see them added to the beginning of the thread, and I'll gladly post them in my blog...
Ok then, that's the plan, video and graphs...
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Old Dec 20, 2012, 07:52 AM
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USA, NH, Alstead
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New Quad Frame Landing Gear

Here are some pics of the new "short" Quadframe landing gear. I replaced my outboard "legs" with this gear. I like it much better as the legs tend to catch on the grass and make takeoffs a bit more shaky.

The new gear is nice and very stable and the CG is nice and low. The GPS coordinants are 0,0,0. There are no legs in the way of the prop blast or the camera.

I like running two 2200 mah batteries in parallel, and like them mounted on the legs as the wires are out of the way of the props.

It is available here: http://quadframe.com/collections/qua...e-landing-legs

Not inexpensive, but very nicely made.

I have the much taller 155mm version on my hex and it has also been great.
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Old Dec 20, 2012, 08:04 AM
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Quote:
Originally Posted by u2builder View Post
Here are some pics of the new "short" Quadframe landing gear. I replaced my outboard "legs" with this gear. I like it much better as the legs tend to catch on the grass and make takeoffs a bit more shaky.

The new gear is nice and very stable and the CG is nice and low. The GPS coordinants are 0,0,0. There are no legs in the way of the prop blast or the camera.

I like running two 2200 mah batteries in parallel, and like them mounted on the legs as the wires are out of the way of the props.

It is available here: http://quadframe.com/collections/qua...e-landing-legs

Not inexpensive, but very nicely made.

I have the much taller 155mm version on my hex and it has also been great.
Very nice! Are those the legs you were telling me about? What are you using for anti-jello for the GoPro?
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Old Dec 20, 2012, 08:28 AM
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Wow!

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Originally Posted by Cervanchez View Post
Ok then, that's the plan, video and graphs...
You are THE MAN!
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Old Dec 20, 2012, 08:32 AM
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Me Too...

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Originally Posted by Mike_Then View Post
Very nice! Are those the legs you were telling me about? What are you using for anti-jello for the GoPro?
I like it too!
You've done a great job of getting a bowl of spaghetti under control...
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Old Dec 20, 2012, 08:42 AM
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Quote:
Very nice! Are those the legs you were telling me about? What are you using for anti-jello for the GoPro?
Yes Mike, these are the new legs. Took a while to get here from Poland. I don't know if they are stocked in the US yet; weren't when I ordered them.

I haven't flow the GoPro yet, but it is mounted the same exact way as before, under the front lip. I tried various methods of isolation and found that NO isolation gave me the best picture. I think the GoPro can get some type of secondary harmonic when on its own isolation. I really wasn't getting any Jello with the rigid mount.

Also at one point I put little foam balls on the bottom of my old legs. This made a lot of Jello. I think that the propwash hitting the balls on the legs created the problem. I took the balls off the legs and it went away. By this logic I think no legs are the brest option.

I think a nice stable platform with smooth props such as the Graups and low CG should not have a lot of vibration. I also shoot 720 x 60 fps which probably helps.

BTW, I mounted the new gear a bit differently than the designer intended, and I think better. The designer intended for it to attach to those slots in the lips of the quad bottom plate. I put about five thin washers between the black frame and the aluminum angle that attaches to it, to located the aluminum a few mm closer to the center of the frame and allow the aluminum angle to be attached by two of the same bolts that hold the bottom frame of the quad to the quad arms. This takes stress off of the those lips and gives a very solid mounting in my opinion.
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Last edited by u2builder; Dec 20, 2012 at 08:51 AM.
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Old Dec 20, 2012, 09:51 AM
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United States, UT
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Quote:
Originally Posted by jetstuff View Post
What are you hoping to illuminate with your infrared LED's?
The camera is IR sensitive, so I am hoping to iluminate the ground and objects in front of me, with the IR.
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Old Dec 20, 2012, 10:00 AM
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Ir led

Quote:
Originally Posted by m_beeson View Post
The camera is IR sensitive, so I am hoping to iluminate the ground and objects in front of me, with the IR.
I didn't know that they had IR LEDs that could shine that far.
If a conventional LED is any indication, the brightest I've found shines about 15' to 20'.
I wonder if a reflector might help?
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