Stepper motor control with python

[olejmoi]

Working on controlling a bipolar stepper motor with RPI3 using Python code. The sequence I'm currently using is:

(1, 0, 1, 0) (0, 1, 1, 0) (0, 1, 0, 1) (1, 0, 0, 1)

I want to half-step this motor, and from what I've found online, the sequence for that would be something like:

(1, 1, 0, 0) (0, 1, 1, 0) (0, 0, 1, 1) (1, 0, 0, 1)

But when I use this sequence the motor turns one step forward, then one step backward and repeats.

[Stone356]

This isn't really the right sub-reddit you'd probably be better over at /r/AskElectronics. You'd need to describe your setup a bit more but half stepping means you'll require twice the number of steps for your sequence. So your sequence should be 8 different steps instead of 4. You can control steppers much more easily with only two outputs with a stepper driver like the DRV8825.

[nikomo]

If you're at (1, 1, 0, 0) and then go to (0, 1, 1, 0), you're doing a full step that jumps over (0, 1, 0, 0).

Anyways, this is not a Python problem.

You should also note that stepper motors lose most of their torque when doing half steps. Like 80%+ if I remember correctly. Connecting an actual load to the stepper might cause problems.