walking test 3 axis gimbal (shake troubleshooting)
  • Here is a test video (no post processing)
    I really need you guy's opinions on how to remove the tiny shake (it's not much but ruins the shoot)...

    The 3 axis gimbal is carrying a D800 with 14-24mm @ 14mm
    Roll : 5208-180T Power=135 P=25 I=0,02 D=16
    Pitch : 5208-180T Power=125 P=20 I=0,02 D=10
    Yaw : 8017-120T Power=150 P=12 I=0,02 D=15
    Battery is 4S
    Gyro trust is set to 80
    firmware 2.40b6
    motor cage on all axis

    I hope someone can help me.
  • Why are you using gyro thrust ? also if you problem was like mine i would lower I and increase D
  • Start by increasing the overall power to 200except on pitch leave it at 180. Then come back and report after you done this. :-) Of course you´ll have to lower the P to around 15. I have some more tips but only after seeing the result with more power.
  • @Teo it shis your house?? OMG.
    why don't you just buy Movi? ;-)
  • polas I have a movi too...ehehehe and don´t have a house like that ;-) Still Alexmos gimbal gives me footage as smooth as movi...
  • Great tips, I will increase the power, lower P

    Oh and yes it's my house,
    It's a lot more "fun" to build your own system than by one already made.

    Thanks a lot for the replies,
    I will post an other video later
  • If I turn the power up, wouldn't the motor heat up too much ?
    They are already on the spot i think
  • nice footage Kikojiu btw
  • Teo don´t worry...the main power can be at 200 no problem...max. temperature shouldn´t be over 75centigrade :-)
    That power is related to the voltage the board will give to the motors when needed. It will translate into steadiness. It is not that your footage isn´t stable but that´s what you can do to improve. I usually prefer the gyro trust to be 110.
  • i raised it from 130 to 150 and seeing some improvements, but motors are getting hot (i touch the coils and they are hot
    I'm gonna try 200 on roll to see
  • get a temperature gauge 60-70 degrees is ok. Don´t measure the coils touch the exrternal metal. If they were hot you couldn´t touch them :-)
    The pitch is not as demanding as roll and yaw...

  • you are sure the 60-70° is the outside case and not the coils ?

    Thanks for your help
    Gonna go do a test at higher power now
    I'll report soon
  • you are the man Kikojiu
    It's already a lot better
    Gonna raise it again

    What do you do when one of the motors makes a noise (like a hum) ?
    reduce P ?
  • increase D first before reducing P. It means it has either too much power or low D. What happens is that it is reaching the limit for resonance...
    Your D800 needs higher PID´s. When I saw your figures already knew it was low. Anyway what you can do is leaving the gimbal on for around 10 mns and then check the temp. It won´t get much hotter than that. With a 5D I have my 5208´s at around 55 degrees all the time.
  • that's good
    I just pressed use default as a mistake and i have to redo the calibration :P
  • Let me know the final result...
  • damn it
    now it's turning and rolling by itself
    what does the blue arrow represent in the gui ? the red dot is rc input i think
  • should i have the gyro high sensitivity checked or not ? the whole rig is 5kg
  • Tomorrow i will experiment the gimbal on a steadicam arm
    I'll let you know how that goes
    I've just modified 3 tube links to be much stronger as well
    And i'm now gonna work on higher power PID's but need to get a thermometer somewhere first
    The roll motor does get kinda hot.

    Is the 5108-120T stronger than the 5208-180T ?
    I'm wondering if I shouldn't upgrade that roll motor.

    Thanks again,

  • Hi Teo. Those motors are ok. No need to change them yet. Don´t use gyro high sensitivity. Don´t need it. Don´t forget to set the calibrate the accelerometer. It resets when you press default.
  • I've always tuned my gimbal with gyro high sensibility,
    What do i do to convert my high values to normal values ?
  • @Teo as far a I know high sensitivity is just a multiplier 2x. So with it turned off you need to scale all values by 2 (not the power though, just PID)
  • Teo just lower the values to half. In fact the gyro sensitivity multiplies by 2 as pOlas says.
  • Man, i just tried it running in my room and it looks awesome
    Gonna try it in the garden in the morning and i'll post a video
    I hope it's perfect ;)
    And i figured that, even if the power is too high for the motor ( the motors are rarely running more than 3-5 min anyways per shot
    So they wouldn't get too hot...
    I tried removing the high sens and changing the pid to half and to double, but it's acting much better with the high gyro sens on at the moment,
    I'll see for sure in the footage tomorrow

    Also, I've set the gyro trust to 100, what is the theory behind it for handheld ?

    Thanks again,
  • I set it at 110. What it means is the system "trusts" the gyro more and less the accelerometers...the higher you go less acc. and more gyro. I don´t think the power is too high and too hot. Can you touch the motors? If you do without getting burnt they´re ok. :-)
  • Here is the 2nd test from this morning

    PID valus :
    Roll - 20 - 0.01 - 30 - power 185 - 5208-180T
    Pitch - 15 - 0.05 - 15 - power 150 - 5208-180T
    Yaw - 25 - 0.01 - 35 - power 220 - 8017-120T

    Battery is 4S
    Gyro trust is set to 100 (gonna set it to 110)
    firmware 2.40b6

    Maybe some more power to roll again ?
    The result are pretty good actually
    What do you think of the running shot at the end
  • Amazing stabilty :-) I would say it is 99,9% perfect. Try to lower the I on pitch to .03 or .02
    Also raise roll I to .03 and Power on pitch around 175, and let me know what happened.
    I would need to see the gimbal on the stand so I could hear and see how the axis go back to neutral when you upset the axis...specially pitch and roll. I might change somethind on the D but looks very very good. But changing D only after seeing...
  • i'll do that, i'm not so sure why i raised it... maybe i could raise the roll power to 190 but oboe that it starts getting rather hot
    How does yours perfume running shots ? i get a bit of shake - could i expect to be able to remove it or is that pushing it too far ?

    Thanks again
  • Don´t raise roll P yet just I...one thing at a time. change the I´s and pitch power. I don´t see much shake...the thing is you have no reference so your reference is infinity...when you follow someone you don´t see any shakes. Do those chages I sent and try again. You are there... ;-)
  • Gonna do that right now,

    An other thing,
    Everytime i start the gimbal, the yaw axis drifts to the right (about 5° from where it should be) any idea on how to fix that ?
  • Maybe this helps, http://forum.basecamelectronics.com/index.php?p=/discussion/681/yaw-axis-calibration#Item_7

    But it did not work for me.

    I start in follow mode, go to normal mode, move so that yaw is correct and go back to follow mode. This works but is a irritating starting procedure. I have a joystick, but using it to correct the yaw in follow mode causes problems.

    Ps. You lucky guy, to have so well working gimbal ;-)
  • @Teo looks amazing. congrats on tuning it so well
  • Just did a new test ( a bit more of a story) you are gonna like it :
  • the smoke is great! what do they do? kill mozzies or something?
  • yea, we have to fog the place once a month for mozzies, and I've always wanted to film it.
    Taped a wet towel on my face of course :P