ESC RPM Parameters
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What are the functions of the MODAL_IO_RPM_MAX and MIN parameters in px4? They don't seem to actively limit the rpm. The esc parameters (min_rpm, max_rpm) do have an effect, but I was hoping to adjust from px4.
Similar but different question: from the esc-tools I adjusted the min_rpm value to 500, but the motor will never spin below 1200 (as per feedback from esc-spin command). I tried adjusting the min_pwm but that did not seem to help.
Thanks in advance!
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px4 1.14-rc1
voxl-esc modalai_esc_firmware_m0129_3_v0_39_RC5_fb6fd95c -
@hanzichi , the minimum rpm depends on the motor / propeller and battery voltage. Higher kV of the motor and higher battery voltage will result in higher minimum RPM. This is because there is a minimum duty cycle of power that is applied to the motor in order for the ESC to operate. So this determines the minimum RPM.
the MIN and MAX rpm parameters in PX4 are informing PX4 about the capabilities of the ESC + motor.
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the MIN / MAX params in PX4 are used if you are using ModalAI ESC. The define the range of the RPM that the motor / propeller can spin and the mixer in PX4 will scale motor output commands accordingly
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@Alex-Kushleyev
OK, thanks for the reply. It is actually behaving as expected now. At first it did not seem like the PX4 params were having an effect.If I have the understanding correct: On the PX4 side, the controller efforts (0-1) are getting spanned to the RPM MIN/MAX params. The RPM (in RPM units) command is then being sent across the UART to the esc.
