DD2 rotation "steps"
Georgi Iovchev
Member
Recently on my DD2 I noticed when not in game or even wheelbase turned off and when I turn the wheel real slowly I feel someting like steps - zones with increased resistance alternating with zones with no reaistence. I counted 22 steps for a full turn (360 degrees). So approximately step on every 16.4 degrees.
If turn the wheel faster I dont feel the steps. If I remove the wheel rim and rotate the shaft directly, the steps are even more noticeable.
It feels like may be damaged ball in a ball bearing or something like this, but there is no sound of metal or similar.
Is this behaviour normal?
Comments
Perfectly normal for the outrunner motor, nothing to worry about.
Thanks for replying. But is it normal to do it when it is powered off?
Yes.
Especially when it is turned off. It’s the nature of an electric motor with the pole count and the magnets used inside the motor.
Thanks. I am calm now that everything is ok.
Yes it is normal. What you're feeling is the interaction between the ring of permanent magnets and the stator. When the system is powered on, there is an active algorithm that compensates for these 'bumps', which is why it feels smoother. This is also why the motor calibration stage (after a motor firmware update) is important.
The steps will indeed be more noticeable if you turn the shaft on its own. Larger diameter and heavier wheels make this feeling less obvious because they have more rotational inertia.
Thanks Dominic, I understand.
Regarding the motor calibration, in latest 372/3 drivers (and firmware), I think that calibration helps only a little about bumps (in power on state). But with previous 356 drivers and firmware, as far as I remeber, the calibration was a way more efficient in removing the steps.
However during gaming the effect of the steps is almost not noticeable.