ProcBigEasyDriver 0.0.3

PI controller for continously rotating a stepper using the big easy driver in a background process on RPi

Processed_PI_BigEasyDriver

Python class for continuous rotation of a PI controller regulated stepper motor in a separate process

Install

pip install ProcBigEasyDriver

Usage

Here's how this thing works. Once you initialize the object a second process is opened which toggles the step pin up and down at whatever interval is needed to reach to specified motor RPM. This is regulated by a PI controller. The speed and the microstepping regime used can be changed at anytime from the main process. The main process keeps control of the enable pin allowing the motor activity to be gated in the main process.

Basics

  import ProcBigEasyDriver as pbed
  from time import sleep

  #Init a stepper that turns at 10 rpm with no microstepping
  Stepper = pbed.ProcBigEasyDriver(step, direction, ms1, ms2, ms3, enable,
                                   microstepping=1, rpm=10, steps_per_rev=200,
                                   Kp=0.2, Ki=0.1)

  #Enable the big easy driver FETs
  Stepper.enable()

  #Let it go for 10s
  sleep(10)

  #Change the microstepping
  Stepper.set_microstep(2)
  sleep(10)

  #Speed it up to 20 rpm
  Stepper.set_rpm(20)
  sleep(10)

  #Stop the wheel (but keep the object active) for 10s
  Stepper.disable()
  sleep(10)

  #Turn it back on
  Stepper.enable()
  sleep(10)

  #Stop the wheel and release the pins (kill the object)
  Stepper.stop()

Contributors

Code was written and is maintained by (Matt Davenport)[https://github.com/mattisabrat/] ([e-mail])