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GoPro upside down on H3-3D

Discussion in 'Phantom 2 Discussion' started by fxmodels, Aug 5, 2014.

  1. fxmodels

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    So if the cam is upside down, it will be perfectly centered. Perhaps that will stop the yaw from showing the landing gear on the port side... Or... it will start showing BOTH landing gear. I dont know... Balance issues are no big deal. Its easy to balance the mount once its in place. The secret is the USB cable. No standard cable can fit in the slot unless the mount is ground down a little... Then a custom USB mount can be inserted. I am planning on trying this. I think as long as the camera is balanced exactly the same upside down across the central axes then it will be fine. The mount wont know the difference.

    I think the mount could use such a mod for the future. I cant figure out why the mount was made the way it was. Its a mystery.

    -Marc
     
  2. Paul K

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    I was looking into this issue already some time ago ,but with no results ; h32d gimbal has fixed connection board on left side ,and there is no way to relocate it . I have h33d gimbal but not yet installed ,and I don't know if that would work to turned it upside down. The problem is the design of the gimbal is wrong at first place ( wouldn't make sense to design it with lens in the centre ?
    Dji's stereotype is to patch the problems then rather redesign the product from scratch. The problem with leg showing in the picture was already with P1 ,the gimbal was moved bit forward and than with h33d problem is back again ( to fix it ,you have to set the GoPro ,from wide to medium ,and sacrifice some settings on camera). Thera are some gimbals on the market with motor on the side of the lens. I thing in this race to bring as many new product to the market ,there is no time to redesign existing products . scratch.
     
  3. fxmodels

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    The H33D CAN have the camera installed upside down but you have to create a custom mini-profile USB plug that will be just the plug and nothing else. Nearly have to have bare wires for it to fit. I will do this. Like I said it might make BOTH landing gear show! Or none... Moving the entire gimbal forward is possible as well but needs to be accompanied by a similar rearward move of something else of substantive weight on board. I will explain why this balance is critical in my view shortly and this could explain a number of the issues I am hearing on these forums. One way to balance the Center of Gravity again if you move the gimbal forward is to move the battery connector inside the P2 BACK by the amount needed to balance the CG change rather than to add weight... Add a shim that is exactly the width and profile size of the existing back mating plate on the P2 so the battery will still clip in. The shell is styrene so you can use a piece of thick styrene and recreate the little lips that the battery clips attach to. This way the battery will connect be held firmly in place while providing enough mass aft of the CG to allow for the forward move of the H33D gimbal (or any gimbal).
    Personally moving the phantom battery connector back by the 4-5mm it might need may work just fine...

    Now even if you DONT move the battery back slightly to compensate for a forward move of the entire gimbal system I am sure the P2 will fly fine if the camera mount is moved forward a cm or two . I really do think so.

    Here is the important element here I think: The problem is that moving weight around and shifting the Center of Gravity on any multicopter will cause some of the motors to work harder to maintain level balanced flight. This wont be noticeable in general and you can take off and say "Hey that works great!" but it will cause definite dangerous changes to turn and descent profiles and more importantly allow the Vortex Ring State onset to occur easier. The reason is one of physics... If you have one or two motors, say the two forward motors, working HARDER to maintain level balanced descent for instance, if a gust of wind hits the P2, it is likely that the quad can be more easily destabilized by the sudden change in the forces. During balanced flight there is no appreciable net difference between the upward thrust vectors within a narrow acceptable range I would guess. If that upward thrust vector is offset by a gust of wind hitting the hanging camera system, then the forward motors, overthrusting in the case illustrated here will tend to force the front end up at a FASTER rate than if the forward and rear motors were all at balanced thrust. This will tend to destabilize the craft easier. Its best if all four motors feel equal balance forces. I see people putting all kinds of neat gear on the P2 and making side trays and all... What they dont realize is that although the NAZA can certainly compensate for this, the additional strain on those motors to maintain level balance will allow failure conditions easier as outlined above.

    My suggestion is that any changes to the system should be accompanied by a careful re-balance or re-weighting to maintain similar thrust vector values. Its theoretically possible that the increase in runtime gained by preventing overthrusting even in the simple case of level hovering flight would counter the loss created by adding a tiny bit of CG balance weight aft for instance. Run time might even improve for all we know at this point once the load on the motors was more balanced. Just my two cents based on a completely scratch built 52" diameter quad prototype that we built where we had to tune PID loops (the Proportional Integral Derivative setup from the Ardupilot platform). We found that even with the hanging weight balance setup (center of gravity a little bit below the plane of the propellers) that out of balance conditions would cause issues that the autopilot could not counter.

    Another suggestion for stability when making changes is to get the motor arm extenders I have seen online. Adding two inches or so to the diameter of the P2 would enhance stability, increase the rotational moment and make it a little harder for VRS to grab hold. But, THAT wreaks havoc with carrying cases!!! haha...

    So these are just my thoughts if it is helpful to anyone.
    Thanks,
    Marc Dantonio
     
  4. fenris

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    Is it necessary to plug the micro-USB plug from the gimbal into the GoPro?
    I've never tried flying with it unplugged, so I have no idea if the gimbal will act wonky if its not plugged in. Seems like it's only there to charge the GoPro?
    Should be able to install the GoPro upside-down, and just leave the mini-USB unplugged.... right?
     
  5. Paul K

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    The usb connection is for charging (I goes 1 pin ) and video connect as well ;replacing ruben cable ,used on H32D. To counter balance Phantom in caes of moving gimbal slightly forward would be ,by moving tx further back.
     
  6. HarryT

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    Apologies if this is a stupid question, but if the camera is upside-down, won't the picture be upside-down, too?
     
  7. OI Photography

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    What are you, some kind of troublemaker?? :D

    The gopro actually has a setting that lets you invert which way is "up" for situations like this.
     
  8. HarryT

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    These GoPro chaps are fiendishly cunning! Thanks :D.
     
  9. fenris

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    You could always just batch correct the photos in PS later by flipping all 180-degrees. Same with video in whatever video editing software.
    It's an extra step, but I'd be willing if it got rid of the stupid landing-gear sticking into the frame all the time.

    And yes, OI photo is correct, too, in that you can tell GoPro to invert its video.

    Will mounting the GoPro upside down affect the H3-3D gimbal balance at all?
     
  10. HarryT

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    I was thinking more of the difficulties it would pose for PFV flying :).
     
  11. ussvertigo

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    I've considered modifying my left front landing so it does not show up it video. But not so much to be unstable at take off.
     
  12. DesertFlyer53

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    Won't work if you depend on FPV for flying, videos/stills. The video downlink will be upside down.
     
  13. Phantom2_15642

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    When I don't want to edit the landing gear out of the video I will simply mount the GP upside down and invert the video. I just use the GP battery and move the ribbon cable out of the way. It has worked fine for me. I have not modified the strap to hold the GP. Just my 2 cents.
     
  14. Karmaphantom

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    It's a bit of an old post, but is the only one dealing with this problem I found around.
    I allways wandered about the lens not being centered together with why the Gopro is powered by the DJI gimbal.

    I already used the gopro mounted upside down (with no cable attached) and actually the problem with the leg is almost gone if you fly calm.
    Now I'd like to fly FPV with thi setup hence I'll have to use a custom USB connector (I already studied how to do and it wouldn't be too difficult with some soldering and metal sanding).

    @fxmodels did you made your custom kit?

    I'm wondering why Gopro were made powered by the Gimbal without considering the option of removing the Gopro's battery.
    In fact, even if you have a full battery on Gopro, the DJI battery will be depleted hence I would prefer choosing between the following:

    -Saving DJI battery with a Gopro powered by its internal battery
    -Flying with a lighter Gopro (battery weights 26g out of total 76g of the Gopro + battery)

    Hence form my kit I'm planning to connect just 3 wires of the 4 total used by DJI (even only 2 should be enough, but I havent dig into this yet. I only supposed 3 are ok as I have some other USB video kit for the Gopro which only uses 3 wires and doesn't power the Gopro).

    I'll post updates if any.
     
  15. Fyod

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    Just turn your monitor upside down and pull the antennas to the bottom :lol:
    But yea, the GoPro has an upside down setting. Too bad its not automatic like on a smartphone.