Roll gets unstable when pitch is 90 degree looking down
  • I do use the unusual Camera Roll Pitch two axis configuration with encoder motors and the paid firmware version. Everything is ok on roll and pitch, but when the camera is looking down more than 80° the roll is loosing horizon stability and changes a few degrees. Six axis calibration is done, also different positions of the IMU are tested. Does anybody have an idea what can be done?? Any help welcome!!
  • How have you configured it, what FW, video/picture would be helpful
  • Hi Garug, thanks a lot for your superfast reply. FW is 2.55b4 and here I did a little video for you http://sendvid.com/7cx35dt6
  • But how have you configured it, axis order and euler angles. Also I would suggest trying the latest beta 2.59. I am not quite sure of two axis setups, but I think that should work when configured correctly.
  • Ok, I uploaded screenshots of the settings
    euler angles is camera - roll - nick, which is unusual, but correct for my construction. Not sure, what is cam - roll- pitch (L) ?! I dont have a yaw axis.
  • You have very low gain multiplier? also I think 0.12 was the lowest after that it defaults to 1.

    Did you do PID tuning? It is at default values?

    I am not sure why the HW configuration is not available?

    Additional power 250 is meaningless the max power is 255 normal + additional and I would advice not to use any additional power, at least not before it is working well.

    Did you do the motor auto to get inverted right? is 28 the actual pole count.

    Your pitch axis is limited - 20, but you try to tilt it to -90?

    To me it looks like you need to focus performing the basic setup well and removing any additional settings before it is working well.

    This might help http://www.levitezer.com/styled-2/blog-2/files/72d28d8da53e386944cd0f0b42a017b6-29.html

    If this does not work, make a support request for BaseCam, it might have to do with Camera-Roll-Pitch two axis configuration.
  • PID tuning was done and in hand held the stabilisation is fine.

    What do you mean with "I am not sure why the HW configuration is not available?"
    Configuration is CAMERA-ROLL-PITCH, which is choosen, so its available in the GUI.

    I played around with power settings, but this didnt change anything.

    The 28 pole and direction is checked and fine, otherwise it would not work in hand and in all other positions than 90 degree down.

    Limitations are fine, 20 degree over horizon and 90 degree down, this is working, just the turn around in roll when looking 90 degree down.

    Thanks for the video links, I will look through! Is that your page and your gimbals?
  • Yes, it is my page, The pole count must be according motor specifications and inverted status set by auto. That it about works, tele nothing, they could be still wrong. Inverted must be set by auto and poles corrected as per motor specifications.

    "Limitations are fine, 20 degree over horizon and 90 degree down, this is working, just the turn around in roll when looking 90 degree down." I do not understand.

    "Configuration is CAMERA-ROLL-PITCH, which is choosen, so its available in the GUI." no, CAMERA-ROLL-PITCH-YAW is available and what I mean is that I have not tested the two axis configuration.

    And also, on your picture it is greyed out. and on the picture PID is default?

    The pictures are very hard to view because all the pop ups on that page....
  • Oh, Finland! I have been there in February this year..great country!

    Congrats for that page and your developments. Clear design, solid and propper...I like that!
    Ok..going on

    I changed to latest firmware and GUI. Pole counts and inverted or not is ok...did check and auto tune.
    28 poles are ok, I use this motors also in other gimbals, where they work fine.
    I played around with the angle limitations, no change.

    Yes, CAMERA-ROLL-PITCH-YAW is greyed out in "advanced" tab, but valid and choosen in RC Tab ..no idea, why its on both Tabs?!

    I auto tuned PID again.

    I do use a pop up blocker, sorry, didnt notice any pop ups...I used another service here:


    Basic setup looks okay for me. When I use it in hand, the stability is great, just the issue when looking 90 degree to the ground...and this needed for orthogonal photogragphy.
  • Try the different Euler orders, I would try normal. those define on what order RC commands them, not the HW configuration. Could be also Encoder calibration problem.

    Also, would be good to see the users manual, it does really good job describing things. :)

    Over all it looks to me that you have too many things going on, I would Erase it to factory defaults and set everything up again.Not use any advanced settings, additional power, follow, use second IMU for stabilisation, nothing but the essential to get it working and the problem identified.

    And you could send a support request for BaseCam. See support above.
  • RTFM....read the f... manual ;-) ...
    I had in my mind, that the frame IMU is no longer needed with encoder version. But looks like that changed.

    Now I activated it and the result is much better. Perhaps now 5 degree of roll, wenn pitch is looking downward. I will take out the basecam unit itself with its inbuild frame sensor and do also therefore a 6 point calibration. I think that will do the job! I will keep you updated! Thanks for your help, patience and time!!
  • No, with encoders you should not need the frame IMU, maybe for strange startup position detection, not sure but it should not be needed. Yep, the users manual saves you a lot of time.