Controlling YAW Axis Issues (error in getting to final position)
  • Hello everyone,

    I am trying to make a gimbal system such that I can feed it data using the serial API to control the movement of all axis. So, I am able to accurately control the PITCH and ROLL accurately using an IMU. I have a potentiometer on the YAW and though it works, it is always short of where it is supposed to end up. The red dot on the GUI is typically 20 degrees away from where the grey encoder arrow is.

    I have followed the calibration for the encoder as much as a could. I read somewhere that the compass on the GUI and the grey encoder arrow should be moving at the same rate. However, I have consistently found that the encoder arrow is faster than the compass. Is this the issue to my problem? If so, what remedy can I take to fix this? I can’t change the gear ratio such that this issue is fixed.

    I am open to listening to all suggestions as to what I can do to fix this problem overall. I think the above should be enough information about the problem. If not let me know what other information will be helpful.

    Thank you all in advance.
  • Hi Genmaster. You're not going to love my answer, but I've tried (for different reasons) adding a magnetometer (i2c slave to ext. IMU) and found that unless I hang the thing on a rod, at least 10cm away from anything at all, it simply is never accurate and never constant (and even then it has issues with surroundings). For my specific solution I finally ended up adding encoders on all 3 axis (RLS off-axis for YAW and Roll, AS5048a/b on pitch) and all is well. Took me a while to understand that encoders are the only real answer. I'm feeding data to the tiny32 through three different serial ports at the moment (Controlled by my RPi4). hope it helps.