Use of linear PWM Encoder AS5311 instead of rotary AS5600 and readout buy the GUI
  • Hi!
    basically I am stabilizing the gimbal of an original Steadicam. Therefore I stabillize the Steadicam with 2 motors, 1 for Pitch and 1 for Roll. To stabilize the axis and follow my Steadicam operations the alexmos board has to know where the camera is facing. So I need data from the Yaw axis. I have installed a magnet ring with 1mm steps between poles around the Steadicam post for the linear AS5311 Encoder - in total 192 poles. The GUI is reading the data but shows every step of 2mm (from plus to minus to plus again) as a 360° turn (as it would do for a rotary encoder). I want it to show 360° only after 192 poles. I tried to tweak the setting with motor/frame gearing ratio which I set to 192 but nothing happened .- I tried other numbers as well - nothing changed.
    I set my encoder as a MA3 encoder in the GUI because my encoder is 12bit 244kHz as well.

    Can you help me ? Either I have set sth wrong or maybe you can implement sth in one of the next versions?

  • Hello.

    There is no simple solution for that. In the encoder firmware, there is an option to configure encoder-to-motor gear ratio, but I doubt it allows to enter the a value of 192. And the most important problem: after calibration of the encoder, you need to power ON system always in the same position, so the encoder properly detects zero point and start reading angle from it. If you shift even by 2mm (1/192 of full turn) or more at startup, motor will not work properly because the electrical field will be not sycnhronized with magnets.

    The simple solution for steadicam-like gimbals is installing encoder on the second axis, linked to the primary by 1:1 gears, and using regular absolute magnetic encoder.
  • To have the device pointed in the same direction during start is not a big issue. Would you be able to implement my linear encoder?

    I tried to enter the value 192 in the motor / encoder gearing ratio. The value is accepted but still the readings in the monitoring tab are the same: 2mm = 360°.

    Sadly I cannot install gears to the primary axis because it would interfere with the operating and the smoothness of the whole system.