Why does my stepper motor shaking back and forth instead of turning and have no torque?

Question

I've been scratching my head on this one for several days now. Stepper motor is shaking and has no torque. A light squeeze on the shaft will prevent the motor from turning.

Motor does this: https://www.youtube.com/watch?v=6Y3yhuFfnNw

Wiring looks like this: https://imgur.com/a/hTchyNO

Code looks like this: https://imgur.com/KOTkVS9

Exact Motor: https://www.amazon.com/dp/B0B38GHRH8?psc=1&ref=ppx_yo2ov_dt_b_product_details

Exact Driver: https://www.amazon.com/dp/B07BK1QL5T?psc=1&ref=ppx_yo2ov_dt_b_product_details

Exact Arduino: https://www.amazon.com/dp/B008GRTSV6?ref=ppx_yo2ov_dt_b_product_details&th=1

I have confirmed the power supply has the required voltage, more than enough amps, and is connected properly. I have confirmed and re-confirmed the wiring is good and connected well. I have confirmed the motor coils are connected to the board with the correct wire orders. I have confirmed the arduino is connected to the driver board with the correct pins in the correct order. I have confirmed it's not dead/bad hardware, as the video above is with new parts that came in literally two hours ago. Same issue with previous identical hardware.

I'm not sure what else to try. Anyone have any suggestions?

Answer 1

Your motors are skipping steps. Your electronic is creating a rotating field inside the motor and the rotor shaft is not able to follow and stay in sync with that field. It just stays still and vibrate.

Some possible reasons:

• Too much acceleration. You can't go from 0 RPM to max speed without a ramp up. The rotor won't be able to follow an infinite acceleration of the rotating field. Make sure you are using a ramp, in your code, to progressively increase the speed of the motor.

• Not enough current. Make sure the driver is set to provide enough current. But pay attention to the max allowed for the motor in the datasheet and also the motor will heat up a lot with higher current.

• Bad wiring or missing coil. If one coil is not connected, you may observe the same behavior.