SequentMicrosystems_API/scripts/speed_reader.py

from src.variables.service import get_variable, set_variable
from gpiozero import Button
import datetime

pulses_per_rotation = 4
reader = Button(4, pull_up=False, bounce_time=0.0005)
set_variable("speed_reader_last_impulse_time", datetime.datetime.now(), False)
set_variable("actual_rpm_unfiltered", 0, False)
set_variable("impulses", 0, False)
set_variable("last_calc_time", datetime.datetime.now(), False)


def event():
    actual = datetime.datetime.now()
    last = get_variable("speed_reader_last_impulse_time")
    difference = (actual - last).total_seconds()
    set_variable("speed_reader_last_impulse_time", actual, False)

    rpm = (60 / difference) / pulses_per_rotation
    
    actual_rpm = (float(get_variable("actual_rpm_unfiltered")) + rpm) / 2
    set_variable("actual_rpm_unfiltered", rpm, False)

    set_variable("actual_rpm", round(actual_rpm, 1), False)
    print(round(actual_rpm, 1))
    


def new_event():
    set_variable("impulses", int(get_variable("impulses")) + 1, False)

def speed_calc():
    now = datetime.datetime.now()
    last_time = get_variable("last_calc_time")
    set_variable("last_calc_time", datetime.datetime.now(), False)

    impulses = int(get_variable("impulses"))
    set_variable("impulses", 0, False)
    time_delta = (now - last_time).total_seconds()

    actual_rpm = (impulses/pulses_per_rotation) * (60/time_delta)

    last_rpm = float(get_variable("actual_rpm_unfiltered"))
    set_variable("actual_rpm_unfiltered", actual_rpm, False)
    actual_rpm = (last_rpm + actual_rpm) / 2

    set_variable("actual_rpm", round(actual_rpm, 1), False)
    print(actual_rpm)
    



reader.when_pressed = new_event