Stuttering Pans and shaky footage /w Letus Helix
  • I am quite experienced with setting up 3-axis gimbals, and have had success setting up custom PID settings on other gimbals, but I can't for the life of me get my helix working properly. It was very, very shaky, so I ended up increasing the values until I found a good number. The main problem I have is that my pans are so jittery, not smooth at all, seems like some stuttering going on, as if it's lagging.

    Here is a video to show that it is properly balanced, though on my FS7 it is front-left heavy due to the LCD screen, and adding weights at the back makes it back-heavy. It evens out, but when I tilt I'm sure that causes some problems, not sure how that can be fixed other than taking off the LCD, which I can't at the moment.

    And here is a video sample from one of shoots, along with stabilizer analysis:

    I found out that taking off LPF off from follow mode helped take the "lag stutter" down quite a bit. Now it's much more usable than the clip I uploaded, but still not as smooth as my other stabilizers. What can I do to smoothen the pans?

    I would appreciate any help. Thanks!
  • Balancing, Roll is ok, it looks like handles are too high up and that it is back heavy, lower the handles and move it from yaw motor froward. (but it is a bit difficult to say from the video) You should be able to but it any position and it should stay there.

    Maybe good to have some LPF. If taken completely of you could try acceleration limit (RC tab)

    Try also high expo.
  • Thanks Garug,

    I tried lowering the handles it still does the same thing because its front left heavy due to LCD screen, and back heavy due to weights so it will shift like that no matter what unless I remove the viewfinder.

    I was wondering if yu have to remove the viewfinder to have proper balance.... but I cant work like that. Not sure what to do.

    So anything I can do with the PID settings?
  • at 0:42 it looks like back heavy? PID will not help for unbalance.

    It just looks unbalanced, but from the video it is not possible to see how. But it in 90 degrees to different positions and balance all axis. they must stay in any position you put it into, like the roll now. the roll looks good.

    Can you move the screen? you can also use additional weights. (any weight on right place to balance the gimbal.)

  • Oh, that's why you thought it was unbalanced. At 0:42, I am pushing it forward with my right Thumb so show you that the handles are balanced... I am pushing it forward and backwards after showing that it does not tilt down or back for a second.

    So do you think I should try to balance the front? I was thinking of adding some kind of weight. I will try and let you know

  • Finally fixed! For records sake, if anyone has a similar setup:

    I contacted Letus and they told me that the viewfinder making front-left heavy is not a problem. You have to lock down the pan when balancing, unlike other gimbals.

    Once you balance perfectly, you have to adjust the PID settings. Take off LPF that messes everything up for some reasons. Put all to 0 LPF

    The problem I had with the FS7 was that it's so long that the Helix has trouble keeping it from shaking left and right. So I increased pan "P" to 70, and "D" to 78, and it solved almost all panning shakes.

    Also if you have the new Helix, make sure poles are set to "22", not "42" since the new motors are 22 poles.

    Then I also adjusted tilt/roll until it stops shaking/vibrating. Now I have a perfectly working helix :)