S900 Inspection Rig

[maxx4wd]

A typical photo of my S900 inspection rig...this thing is on the bench more than in the air...when if flies it's awesome but boy way way way too much work...plus about to downgrade to the inspire with x5 or the yuneec - can't decide which...like the idea of the S900 but sick of messing with it. - photo below is my last attempt to get rid of some very poor harmonics that are getting transferred through the landing gear to the gimbal when the gear is up...(this one has suffered from pretty poor dynamic vibrations for the last few months...trying out some prototype props from xoar and hoping that might help in addition to all the standard tweaks and tricks...hoping to get it perfect and sell it...LOL)

 

[maxx4wd]

Maybe my last post was a bit too negative - I'm usually a pretty upbeat person...so I'll follow it up with a more positive one...a few of my buddies and I love to fly anything but DJI is one of our favorites - especially the inspire...we have some that have infrared cams on them - some that have the standard x3...we do a bunch of mapping and 3d rendering with both the inspire and the P3 (and to a lesser degree the P2)...between the lot of us we pretty much cover the current industry (short of filming for big budget movies - we all are dads and have professional day jobs so can't just take off a day or two to fly but maybe someday)...anyhow we have a ton of crap...not just DJI but some solos and soon some yuneec stuff. we teach classes at the university to beginners most of us have a 333 or coa's...and we fly whenever we can...hopefully I can contribute to some good discussions and help whomever I can...

 

[Petr Hejl]

A typical photo of my S900 inspection rig...this thing is on the bench more than in the air...when if flies it's awesome but boy way way way too much work...plus about to downgrade to the inspire with x5 or the yuneec - can't decide which...like the idea of the S900 but sick of messing with it. - photo below is my last attempt to get rid of some very poor harmonics that are getting transferred through the landing gear to the gimbal when the gear is up...(this one has suffered from pretty poor dynamic vibrations for the last few months...trying out some prototype props from xoar and hoping that might help in addition to all the standard tweaks and tricks...hoping to get it perfect and sell it...LOL)View attachment 18

Maxx4wd, that's a nice collection. Your post about the harmonic vibrations in your S-900 is not terribly negative, they did have these issues. I got mine sorted out and now it's a great machine (it took a while though). Here's what I did to stiffen up the frame: 1-epoxied the carbon fiber cross bar between gear legs onto the knobs it sits between (I assume that's what you were doing in the pic. 2-I upgraded the motor plate dampeners to the softer ones (they are a DJI upgrade/replacement part). 3-I replaced the top plate with a thicker, beefier one from Kopterworx. This fixed my S-900, there are no vibrations at all now.

 

[maxx4wd]

Maxx4wd, that's a nice collection. Your post about the harmonic vibrations in your S-900 is not terribly negative, they did have these issues. I got mine sorted out and now it's a great machine (it took a while though). Here's what I did to stiffen up the frame: 1-epoxied the carbon fiber cross bar between gear legs onto the knobs it sits between (I assume that's what you were doing in the pic. 2-I upgraded the motor plate dampeners to the softer ones (they are a DJI upgrade/replacement part). 3-I replaced the top plate with a thicker, beefier one from Kopterworx. This fixed my S-900, there are no vibrations at all now.

Petr,

Yes this picture was the epoxied cross bar fix...and like you I also did the kopterworx top plate...in addition to the more rigid top plate it looks way cooler too... I have done the pillow ball dance on the gimbal plate but have yet to do the replacements of the motor plates...I'll have to look that up. I ordered litterally every single damper that DJI made and a few aftermarket options as well...so I bet that I even have them already...right now I only get a little high frequency jitter when the gear are raised so I'm hoping the cross member epoxy fix will help this...also interested to see how these xoar props help (if any) but it is a process for sure - just very annoying when your battling harmonics on a "pro" grade copter...as an engineer nothing makes me more frustrated then poor design...especially since this could be fixed by going away from temperature influenced rubber dampers and using steel hoops like all other pro grade copters....

 

[maxx4wd]

Ok any S900 users out there...experiencing any issues with the latest IMU update...
I updated the GH4HD gimbal and it also updated the IMU firmware...my copter was operating fine prior to this update (expect for some jello issues which I think I've got nailed down - but can't test due to this new software issue)

My issue now is that the A2 had decided to give me constant blinking red light upon startup - mode switch doesn't change anything just constant red flashing lights - I looked it up and it's either throttle position out of range (which it's not I re-calibrated everything just in case) or its a miscalibration of the GPS antenna (which is likely as I tried to recalibrate the antenna after the IMU update as one should always do). in A2 Assist I show strong satelite strength (over 12) - I'm recalibrating in a metal free area (no known magnetic fields around either) get into calibration mode - blue light stays light while I do the horizontal dance - green light stays lit till I get the 360 vertical dance then immediately red blinking lights....

copter was just fine before the Gimbal and IMU update...

tried de-gaussing - did nothing

any ideas? I'm fresh out.

 

[maxx4wd]

Nevermind...NOOB101 in session...

Well chock one more up on the noob list...I forgot to hit DJI's stupid little hardware unluck in the A2 assist before wasting tons of time and not figuring out what the flashing red lights meant...won't do this one again...leave it here just in case someone wants a good laugh or actually doesn't repeat my mistake...anyhow hopefully I'll be able to report how these new xoar prototype props are working below instead of issues any noob could figure out...