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Old Oct 21, 2012, 11:39 PM
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Originally Posted by jcmonty View Post
Ya, I could have said that a bit more clearly. Yes
I tried today but failed. I was shooting some video on a job but the wind was blowing pretty good and there were a lot of turbulence. My Y6 gain was a bit too high and it was oscillating. I didn't have a computer to tune it. I managed to salvage a 20 seconds clip from one flight and switched over to another machine with the Sony PJ710V camera. The wind was so bad even the footage from the PJ710 was shaky.

You have to realize most demo footages you saw were captured during almost perfect weather condition. No one likes to show you raw images that doesn't show off their products.
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Old Oct 21, 2012, 11:41 PM
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Originally Posted by Jeffem62 View Post
Thanks

And your servos?

Nice video by the way
I am using a Hitec HS5995 robotic servo on roll. It has 180 degrees travel. It is discontinued but the price was right from Servo City so I bought a few.

The tilt is a MKS servo I got from Andrey. He modified it with wires sticking out for me to hook up to the external pot. I am not sure which MKS is that. He sent me two and this one has no label on it.
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Old Oct 21, 2012, 11:46 PM
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Originally Posted by tomeparker View Post
Do you think you could get the gimbal to work that good with a Naza? Apparently the Naza isn't as good at gimbal control compared to other FC such as the CC/CC3D.
Well I am not sure. CC3D is ok but the gimbal control is still very limited. There is really only one gain to adjust and I have a hard time getting the tilt travel to sync with the multi rotor movement. I am getting it about there but there is still some over/under compensating going on.

The Naza M is not the best but you can still tune the gimbal gain to a fairly decent compromise. It will never be locked in especially on the tilt. I managed to get the roll on the Naza working pretty well. Again the Naza only has one gain to tweak so you just have to compromise.

It seems like the only way to get a good gimbal control for now will be the HoverFly Gimbal control. I tried using my Multi Wii board for just some rough test but at the time there is no tilt control pass through on the Multi Wii software. I am not sure if it has now.
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Old Oct 21, 2012, 11:53 PM
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>>I still need to tune the gimbal some more and I know I can see some vibrations, but I'm not sure if they are from my motors (some of which don't spin as smooth as they used to - I'm looking into new bearings) or from the gusts of wind hitting the copter / gimbal. I'm also wondering if my gimbal to UAP mount might need more work.<<

Forget about the motors. I think the vibration/oscillation is such low frequency that it is probably propellers or something else. Probably wind or vibration isolators. I think we need more than 1 layer of vibration isolation on these gimbals. Also a smaller diameter propeller will get the motors to spin at a slightly higher RPM therefore increasing the vibration frequency.

>>As for the gimbal / servos, with smaller or slower movements it seems to be doing pretty good, but with larger or quicker movements it looks like it isn't keeping up on either axis. I should have another chance tomorrow evening to get in at least one more flight, hopefully it won't be as windy and I will make sure I have a fully charged battery!<<

Yeah It will be great by the time we can get these gimbals to track exactly even with large movements.

The short video shows that the gimbal is working as it should. It is just a matter of fine tuning. We have lots of testing and tuning to do.

I really like how you have only very small amount of shakes right at take off. That means your machine is pretty well balanced.
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Old Oct 22, 2012, 01:22 AM
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Originally Posted by jcmonty View Post
Ya, I could have said that a bit more clearly. Yes
Here you go. I just put something together to show you how bad it was:

20121021 2 axis gimbal gusty wind GH2 (1 min 30 sec)
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Old Oct 22, 2012, 01:38 AM
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Wow, now that 's flying in wind. Thanks for the clip! Amazing how well it stabilized even with the turbulence. Do you think that was just turbulence or was there some oscillation that could be tuned out?

The CX/PJ series of cameras have pretty amazing stab systems as this clip proves once again.
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Old Oct 22, 2012, 03:20 AM
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>>Do you think that was just turbulence or was there some oscillation that could be tuned out?<<

I had the gain on the CC3D set too high. So it was turbulence induced oscillation. I could actually see the Y6 oscillating from the time it took off. The smooth part was when I had the Y6 leaning sideways into the wind. That probably took some of the oscillation off. With the CC3D I can only adjust the gain when I hook it up to the computer. I don't have wireless tuning on the setup.
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Old Oct 22, 2012, 05:27 AM
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Quote:
Originally Posted by SeismicCWave View Post
The Naza M is not the best but you can still tune the gimbal gain to a fairly decent compromise. It will never be locked in especially on the tilt. I managed to get the roll on the Naza working pretty well. Again the Naza only has one gain to tweak so you just have to compromise.
Seismic.
The manner in which the Naza only has one gain to tune, would this oversight be remedied by having the roll and tilt mechanism's on the gimbal to have the same servo's, the same pulleys and pulley ratio's, and exactly the same distances and dimensions of fit-out for the roll and tilt mechanisms?

That should help, no?
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Old Oct 22, 2012, 05:45 AM
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Hi

Is there still no price approximation for the kit ? I keep on asking because I'll be buying a gimbal for one of my quads in the next two weeks… and I kind of hoped this would be it…

Thanks
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Old Oct 22, 2012, 01:03 PM
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Originally Posted by Noob Mike View Post
Seismic.
The manner in which the Naza only has one gain to tune, would this oversight be remedied by having the roll and tilt mechanism's on the gimbal to have the same servo's, the same pulleys and pulley ratio's, and exactly the same distances and dimensions of fit-out for the roll and tilt mechanisms?

That should help, no?
Sorry I am not clear in my post. When I said there is only one gain to tune I meant one gain for roll and one for tilt. On the HoverFly gimbal controller you can tune the gain, servo travel and some sort of feedfoward called acc for each axis.

The main thing is to be able to adjust the travel and reaction speed of each servos so they will "track" with the movement of the multi rotor.

The Naza tie the servo travel to the gain. So the more sensitive you adjust the gain the more servo travel you get. So it is really easy to get either a overshoot in the compensation or under shoot.
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Old Oct 22, 2012, 01:07 PM
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Originally Posted by Diafragma1939 View Post
Hi

Is there still no price approximation for the kit ? I keep on asking because I'll be buying a gimbal for one of my quads in the next two weeks… and I kind of hoped this would be it…

Thanks
I cannot speak for Rusty. However I am pretty sure you will see some form of kits in two weeks. At least I hope so.

As far as price, again I cannot speak for Rusty. My personal feeling is that it will not be over $300 without servos. So you can count that as the high side.

IMHO I would think between $150 to $200 for a kit that includes the plates, Delrin blocks, camera tray, pot, pulleys and belts would be reasonable. I calculated the material costs for my carbon fiber tube build at retail costs. I was at $210 without servos.
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Old Oct 22, 2012, 01:14 PM
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Quote:
Originally Posted by SeismicCWave View Post
I cannot speak for Rusty. However I am pretty sure you will see some form of kits in two weeks. At least I hope so.

As far as price, again I cannot speak for Rusty. My personal feeling is that it will not be over $300 without servos. So you can count that as the high side.

IMHO I would think between $150 to $200 for a kit that includes the plates, Delrin blocks, camera tray, pot, pulleys and belts would be reasonable. I calculated the material costs for my carbon fiber tube build at retail costs. I was at $210 without servos.
Would be great if that was the case!
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Old Oct 22, 2012, 02:33 PM
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Quote:
Originally Posted by SeismicCWave View Post
Here you go. I just put something together to show you how bad it was:

http://www.youtube.com/watch?v=0IDJmUVGytc
Psssh! You need a helicopter for conditions like that. Check this out. About halfway through I show some footage from a camera that is hard mounted, no gimbal at all.

Extreme Wind Testing (4 min 54 sec)


Flybars may be old school, but they work amazing in conditions like this when combined with a gyro system.

But seriously, your last "ball test"... man, that's amazing. "One Gimbal to Rule Them All". Open Source FTW.
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Old Oct 22, 2012, 03:00 PM
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I've been sitting here thinking about building a gimbal as I wasn't happy with the one I've got when I came across this post
Brilliant just what I was thinking about
Count me in for one
Cheers
Joe
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Old Oct 22, 2012, 03:46 PM
Vulcan skyhook multirotor
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What is the pot for and where does it connect?
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