CAN bus - Current Measurements

We are developing a lower part of a humanoid robot. It has 12 DOF and we use 6 ODrive controllers (one controller for two motors) that are connected via CAN bus. We already tested robot to make squats and lateral movements.

Before we test robot to make walking sequence I need to measure current on each motor (Iq_measured) to calculate torque. For some reason data that I receive from CAN bus using Get_Iq (0x014) command is quite a bit different from multimeter measurements. It provides figures that 10-15 time more than multimeter’s figures.

If someone has previous experience of measuring current via CAN bus can you please share your thoughts why this happens?

What current are you measuring with you multimeter ? is it the current from the battery ? If so, it’s normal that both current aren’t equal.
If it’s the case, the power must be equal (battery power == motor power). As your motor aren’t spinning really fast (I suppose) then your voltage is low --­­> hence your motor current must be high to equal the power of the battery. Which corresponds to 24V or 36V times a little current.

Hope it was your case and sufficiently clear !

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