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Feb 27, 2012, 01:49 PM
Z06 Tony's Avatar
Quote:
Originally Posted by GGoodrum
I'm not sure about where Adidas' gimbal is positioned, but on the F550 setup, the camera is back far enough that prop wash is not an issue. I just don't see the same sort of vibe levels he's seeing at all. Adidas, how is your setup connected to the frame? One late change we've made for the F550 and F450 mounts is to add rubber grommets in the slots on the F550 lower plate. The bolts from the landing gear legs go up through these grommets, so there's a 2nd layer of dampening now, with a different range of resonant frequencies than the isolators used on the gimbal mounting plate. Although this doesn't look like it would help the problem of reducing the vibes getting to the FC, it actually did on my setup. I think there was a feedback issue I had where the an oscillation was being caused by the LG vibrating. Isolating the LG made this go away.

I like Andrey's idea about trying to isolate the motors. This would definitely reduce, if not totally eliminate, the problem of vibes getting to the FC and causing gimbal "corrections".


Here's another view of the same gimbal test I did yesterday:

http://youtu.be/vrWBWwdyeqA

Today, weather permitting (it is very windy at the moment...), I will do a test flight. to see how well this HX9V works in this setup. I think I have the gains about as close as I can get them.

-- Gary
Hey Gary can you please post your F550 settings when you get a chance. Not for the gimball. Trying to get mine dialed in. I know if out weight is diff the settings will not work as good for me but will be able to see if 1 of my setting is alot diff than yours. Have just a little wobble I am trying to get rid of.
Thanks
TONY
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Feb 27, 2012, 03:53 PM
manual flying apologist
Adidas4275's Avatar
Mine is hard mounted to a sheet of 1/4" G10. It is possible that vibrations are going up thought the LG and to the FC

I'll add some vibration dampening material between.
Feb 27, 2012, 04:16 PM
Registered User
Quote:
Originally Posted by Z06 Tony
Hey Gary can you please post your F550 settings when you get a chance. Not for the gimball. Trying to get mine dialed in. I know if out weight is diff the settings will not work as good for me but will be able to see if 1 of my setting is alot diff than yours. Have just a little wobble I am trying to get rid of.
Thanks
TONY
+1, I would also love to get your settings for the f550 and the f450, you really seemed to have that dialed in.
Feb 27, 2012, 04:21 PM
Z06 Tony's Avatar
Quote:
Originally Posted by Adidas4275
Mine is hard mounted to a sheet of 1/4" G10. It is possible that vibrations are going up thought the LG and to the FC

I'll add some vibration dampening material between.
This stuff rocks. i use it alot-> http://www.amainhobbies.com/product_...ng-Gel-1-Sheet
Feb 27, 2012, 06:52 PM
manual flying apologist
Adidas4275's Avatar
tony I just bought 3 sheet of that.... should be here tomorrow... love being in CA and having so many online hobbystores in CA as well.

I am hoping I can get rid of the vibs... otherwise I will tear my build down and just work on my RC-Carbon Frame builds with new motors sunnysky 2814s
Feb 27, 2012, 11:07 PM
formerly Juddkleinman
Mountain Soarer's Avatar
GWS 3 blade prop question.
Did you have to reem the prop to get it to work with the DJI motors?
Feb 27, 2012, 11:29 PM
Registered User
R Hudson's Avatar
I believe that some of the GWS props have an 8mm center bore. However, the ones I bought did not so I had to ream them. I used (per Gary's recommendation) a 5/16" drill bit by hand on a flat surface. If you are not comfortable with that idea you can use a drill press but be careful. The bit may bite into the plastic quickly and send it spinning.
Feb 28, 2012, 12:00 AM
Registered User
GGoodrum's Avatar
Thread OP
Tony, I'll have to hook the MC up to the Assistant, to know for sure, but my Basic Gains are about 105, 105, 120, 120. The Attitude gains are fixed at 95%. My AUW is 6lb 10.5oz, and I'm using 10x5 Graupners, on two 4s-3300 packs.

If you are getting wobbles, chances are you might be over-propped, for the weight. Both the WK-M and the Naza don't like light disc loading. I've noticed that when the loading is right, the gains can vary over quite a range, with no apparent change in the stability. In fact, I've tried to change it over the whole variable knob range, from 50 to 300%, and the only real difference is that I got a slight oscillation above about 250%, and it "groaned" on decent, with the gains under about 75%.

-- Gary
Feb 28, 2012, 12:03 AM
Registered User
GGoodrum's Avatar
Thread OP
Quote:
Originally Posted by R Hudson
I believe that some of the GWS props have an 8mm center bore. However, the ones I bought did not so I had to ream them. I used (per Gary's recommendation) a 5/16" drill bit by hand on a flat surface. If you are not comfortable with that idea you can use a drill press but be careful. The bit may bite into the plastic quickly and send it spinning.
Yep, a 5/16" drill bit is what I used. I did it by hand, with a pair of pliers. You just need to keep the bit straight.

-- Gary
Feb 28, 2012, 12:12 AM
manual flying apologist
Adidas4275's Avatar
okay guys I am making progress... you can really see the potential of the gimbal in this latest video.... it is not perfect (YET!) but it will be soon. I was really banging on the sticks in all four directions and flying in my ground effect almost the entire time with walls and cars near bye creating all kinds of turbulence and other than a little shaking it looks quite good!

I believe my 4s5000mah battery. nex-5 and the gimbal weight is too much for the 6 vibation isolators and that is causing them to squish too much. I could add 2 more, but i dont have any more.... I do have 6 others that are higher weight ratings.... might cause new problems, but tomorrow I will switch them out and see what that looks like.

Video should be live in about 1 1/2hrs..... slow upload speeds tonight!
Progress with the Askman gimbal nex-5n HoverFly Pro stabilized multicopter test flight (6 min 56 sec)


thanks for all the help guys
Feb 28, 2012, 12:44 AM
Destroyer of G-10
askman's Avatar
if you need few more isolators, let me know. you probably need 8-10 , I can send 2 more. no biggy. I believe gary settled on 8 as well.

gary will carry them on his website as well in case you need replacements.
Feb 28, 2012, 12:57 AM
manual flying apologist
Adidas4275's Avatar
Quote:
Originally Posted by askman
if you need few more isolators, let me know. you probably need 8-10 , I can send 2 more. no biggy. I believe gary settled on 8 as well.

gary will carry them on his website as well in case you need replacements.
pmed you, i think 8 would be right.... for the nex-5n, gimbal and 4s5000mah

I have a 4s2200 pack that I am going to fly tomorrow and see if that gets rid of the bouncing that I got tonight. I have almost completely eliminated the servo twitch that has plagued my videos so far... now the camera just bounces up and down, especially when I am hovering and when I am in the ground effect.

I ordered a bunch of vibration isolating grommets from rusty (AGLHobbies) to use on my Flight Controller mounting deck and some of that vibration gel stuff.... i also have a bunch of moogel, i use that underneath the battery compartment of the nex-5n. I am also using a rubber washer in between the camera plate and the camera with the tripod screw going threw it.

it is coming along..... I think most of my issue was with 1 damn prop that was really far off on tracking and it was giving a lot of vibrations.....

when my video is live (says 56mins now) you will see major progress! not perfect but closer
Feb 28, 2012, 02:23 AM
Z06 Tony's Avatar
Quote:
Originally Posted by GGoodrum
Tony, I'll have to hook the MC up to the Assistant, to know for sure, but my Basic Gains are about 105, 105, 120, 120. The Attitude gains are fixed at 95%. My AUW is 6lb 10.5oz, and I'm using 10x5 Graupners, on two 4s-3300 packs.

If you are getting wobbles, chances are you might be over-propped, for the weight. Both the WK-M and the Naza don't like light disc loading. I've noticed that when the loading is right, the gains can vary over quite a range, with no apparent change in the stability. In fact, I've tried to change it over the whole variable knob range, from 50 to 300%, and the only real difference is that I got a slight oscillation above about 250%, and it "groaned" on decent, with the gains under about 75%.

-- Gary
Thanks Gary. I will lower my gains some more.
LOL talk about over-propped. I am surprised your motors are not burnt up. They def shouldnt be running 10" props on 4s. I hovered mine for 2 mins inside on 4s with 10" props and only 1 2200mAh 4s pack and my motors were hot.
Your carrying 6.5lbs with a stock F550
Feb 28, 2012, 02:40 AM
Registered User
GGoodrum's Avatar
Thread OP
Quote:
Originally Posted by Z06 Tony
Thanks Gary. I will lower my gains some more.
LOL talk about over-propped. I am surprised your motors are not burnt up. They def shouldnt be running 10" props on 4s. I hovered mine for 2 mins inside on 4s with 10" props and only 1 2200mAh 4s pack and my motors were hot.
Your carrying 6.5lbs with a stock F550
Actually, this is not a problem at all. Even after 10+ minute flights, the motors are not much more than ambient.

-- Gary
Feb 28, 2012, 11:17 AM
Registered User
GGoodrum's Avatar
Thread OP
BTW, both my F450 quad and this F550 hex ran hot with the stock 10" props. I don't know why, but with both the 3-bladed GWS 9x5x3s, and with the 10x5 Graupners, the motors run cool as a cucumber.

-- Gary


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