Phobotic CenterPiece Owners Thread.

Motopreserve

Drone Enthusiast
Based on the description - there is definitely something off on the roll balance. As Violet mentions, the camera should stay in in any position it's left in, not "returning to level after any disturbance."
 

jdennings

Member
Thanks so much guys.

Here's a pic of my test set-up. (The wide angle lens I used distorts things somewhat, the bottom of the gimbal looks like it's sitting on the table but there is actually plenty of clearance, also the horizontal tubes are actually level and vertical perpendicular ). For starters I should definitely get rid of that leash ... given it's extremely low weight I thought I could get away with it ... Also I am going to add some weight to the small coffee table I used to suspend it. Legs did move very so slightly during tuning, but I thought this would be way less than under the copter (on ground) so discarded that ...

Re: Roll balancing. Seems to me there is just no way, given the geometry of that gimbal and the roll pivot point, to actually roll the camera 20 degree, say, and have it in place, right? (Unlike some other gimbals). So what does roll balancing mean? Isn't the best you can do balancing the camera and tweak the position of the clamps so that weight is exactly distributed equally under both side of the roll motor axis? The second you roll that axis it is going to want to go back to horizontal, given CG is beneath the roll axis?
 


jdennings

Member
Doh!

Can't believe I did this, and didn't even catch it or check. Oh, now I remember. I had stored it in a box and had pivoted it for less space. Still :( ...

Thanks!
 

Motopreserve

Drone Enthusiast
These are the kind of things I do quite often. Everything is perfect....except that one little thing :)

Let us know how you make out.
 

jdennings

Member
So far so good, just did a quick balance with damping plate on, autotune completed and gimbal visually stabilizes on the bench and handheld.

Now on to "perfect balancing" with hard mount and heavier lens (17-40L) I actually plan to use. Also better IMU mounting, I've got a 3D printed box for it.

What kind of wire gauge do you figure would be best to power for this kind of set-up? I went with 18 awg between the "power conditioner" add-on and the board, now think it's overkill. Haven't seen more than 1A (on 4S) when I stuck an ammeter so far no matter how the gimbal moves, (with heavier lens , 1.45 kg camera + lens weight) , so thinking 20awg is plenty ...

Any screenshots of what the gimbal analyzer tests give for a similar weighted set-up and "perfect" set-up?
Here are mine so far for pitch and roll, I suspect real ugly (especially roll) given my quick test and rough balancing, and I should/will do much better. Just wondering what king of graph and faster response/converging I should shoot for ...

Psyched so far, but of course the proof will be in the "video from the air" pudding ...
 

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jdennings

Member
Here's the example graph from the Phobotic manual of an example of a well tuned axis. Wondering is that sort of graph is achievable with Legacy and 1.5kg camera load.

At least a good target to aim for ...

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Motopreserve

Drone Enthusiast
Looks like you're well on your way. I wouldn't worry too much about the graph until you have the camera balanced well.
 

SamaraMedia

Active Member
Graphs, graphs and more graphs...

Here's a test flight of my Tarot X6 with Quadframe DSLR gimbal, Photobotic CP, with Sony HDR CX580 video camera, 1000mAh 3s battery for power. Used a GoPro mounted on the arm to monitor the gimbal action. FPV pilot camera also in split screen to see actual flight attitude. Sometimes it seems pretty good but other times really jittery. FFF doesn't look as bad as some of the slow cruising footage. Need to take it off auto-focus too and make sure IS is off. Will need to look at the graph for what it's doing. Quick autotune done a few weeks ago, feels OK handheld, different story in the air. Will need to also look at all the fps settings. FPV cam is 23.98 (weird file format), GoPro 1080p 30 fps, Sony cam 1080 fps. Converted them all to H.264 with Aiseesoft since its one of the few programs I've found to convert the Pixim Seawolf FPV cam file. Camera seems to search for focus sometimes which doesn't help quality.

 

jdennings

Member
That gopro view of the gimbal is very cool! Did you use one of those bike handlebar mounts?

Gave up on mine, until I get a different camera or lighter lens. That Legacy with 52xx motors is just not cutting it for that camera/lens weight combination and CP, after perfect balancing could sorta make it work handheld, but lots of resets/recovery and graphs looked like hell, so I don't even want to think of how it would be in the air ...
 

SamaraMedia

Active Member
Standard GoPro housing mounted with gaffer tape.

I will have to check balance again and graphs for gimbal but still needs work. Vibes on frame are low, around .04, compared to the last test flight.
 


SamaraMedia

Active Member
Thanks Motopreserve. 397g on cam. Probably gonna have to find something else in the end since it doesn't have any video out that I can find.
 



Cameraj

Member
That gopro view of the gimbal is very cool! Did you use one of those bike handlebar mounts?

Gave up on mine, until I get a different camera or lighter lens. That Legacy with 52xx motors is just not cutting it for that camera/lens weight combination and CP, after perfect balancing could sorta make it work handheld, but lots of resets/recovery and graphs looked like hell, so I don't even want to think of how it would be in the air ...
I have moved on myself to the dji ronin, it just works and no more pounding my head against a wall. Anyone want to buy my Cp board and legacy gimbal?
 

tombrown1

Member
Graphs, graphs and more graphs...

Here's a test flight of my Tarot X6 with Quadframe DSLR gimbal, Photobotic CP, with Sony HDR CX580 video camera, 1000mAh 3s battery for power. Used a GoPro mounted on the arm to monitor the gimbal action. FPV pilot camera also in split screen to see actual flight attitude. Sometimes it seems pretty good but other times really jittery. FFF doesn't look as bad as some of the slow cruising footage. Need to take it off auto-focus too and make sure IS is off. Will need to look at the graph for what it's doing. Quick autotune done a few weeks ago, feels OK handheld, different story in the air. Will need to also look at all the fps settings. FPV cam is 23.98 (weird file format), GoPro 1080p 30 fps, Sony cam 1080 fps. Converted them all to H.264 with Aiseesoft since its one of the few programs I've found to convert the Pixim Seawolf FPV cam file. Camera seems to search for focus sometimes which doesn't help quality.


Make sure autofocus is turned off and mf is set to infinity. AF will wreak havoc in the air....
 

jdennings

Member
I have moved on myself to the dji ronin, it just works and no more pounding my head against a wall. Anyone want to buy my Cp board and legacy gimbal?

Did you go with the original Ronin or the Ronin-M? How hard or easy is it to convert from handheld to MR mount?
 



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