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Code: Select all

long steps = 0;   // Pulses from  Optical Sensors
void setup() {
  pinMode(2, INPUT);
  attachInterrupt(digitalPinToInterrupt(2), countSteps, RISING);
}

void loop () {}

void countSteps(void) {
  steps++;
}

Code: Select all

from Phidget22.Phidget import *
from Phidget22.Devices.DigitalInput import *
from Phidget22.Devices.DCMotor import *
import time

def main():
    #Create your Phidget channels
    DigitalInput0 = DigitalInput()
    DigitalInput0.setIsHubPortDevice(True)
    DigitalInput0.setHubPort(0)
    DigitalInput0.openWaitForAttachment(1000)

    dcMotor = DCMotor()
    dcMotor.setHubPort(1)
    dcMotor.openWaitForAttachment(1000)
    dcMotor.setCurrentLimit(4) #Actuator current limit
    
    #------- Do stuff with your Phidgets here or in your event handlers. ------#
    
    #-- VARIABLES --#
    pulse = float(0) #initial pulse = 0
    extrapulse = float(0) #initial extra pulse for deceleration = 0
    test = 0 #variable to test if pulse was already recorded
    timeout = 5 #Time used to record extra pulses when decelerating.
    timeout2 = 2 #Time out time to break the loop
    
    #-- REQUESTED PARAMETERS --#
    move = 1 #actuator position requested in inches
    pulsemove = move*100 #convert inches to pulse (1in = 100 pulses)
    velocity = 0.3 #Actuator speed (MAX 0.5)
    
    
    #-- ACTUATOR MOVES UNTIL REQUESTED POSITION IS ACHIEVED --#
    
    #1. Extend actuator
    dcMotor.setTargetVelocity(velocity)
    
    #2. Read and print initial parameters
    state = DigitalInput0.getState()
    print("Initial pulse: " + str(pulse))
    print("Initial state: " + str(state))
    
    #3. Check and add pulses
    #WHILE current pulse is smaller than requested pulse (position)
    while pulse < pulsemove:
        #Read digital input signal
        state = DigitalInput0.getState()

        #IF digital input is HIGH and pulse has not been recorded yet, THEN add pulse and change test variable.
        if (state == True) and (test == 0):
            pulse = pulse + 1
            test = 1
            print("Pulse: " + str(pulse))
        #OTHERWISE, WHILE digital input is still HIGH (same hole on the encoder disc): wait and read digital input. ONCE digital input is not HIGH, change test variable.
        else:
            while state == True:
                state = DigitalInput0.getState()
            #Reset test variable
            test = 0

    #4. Stop actuator command
    dcMotor.setTargetVelocity(0)
    
    #NOW pulse == pulsemove
    #5. Reset test variable
    test = 0


    #-- RECORD EXTRA PULSES WHILE ACTUATOR IS DECELERATING --#
    
    #1. Record current time
    timeout_start = time.time()
    
    #2. Record extra pulses
    #WHILE current time is smaller than start time + timeout
    while time.time() < (timeout_start + timeout):
        #Read digital input signal
        state = DigitalInput0.getState()
        
        #IF digital input is HIGH and pulse has not been recorded yet, THEN add extrapulse, add pulse, and change test variable.
        if (state == True) and (test == 0):
            extrapulse = extrapulse + 1
            pulse = pulse + 1
            test = 1
            
        #OTHERWISE, WHILE digital input is still HIGH (same hole on the encoder disc): wait and read digital input. ONCE digital input is not HIGH, change test variable.
        else:
            #Record current time to have a way to break the WHILE loop if encoder is stopped and reports a HIGH digital input indefinitely
            timeout_start2 = time.time()
            while state == True: 
                if time.time() < (timeout_start2 + timeout2):
                    state = DigitalInput0.getState()
                else:
                    break
            test = 0
            break
    
    #3. Print extra pulses recorded
    print("Total pulses: " + str(pulse))
    print("Extra pulses: " + str(extrapulse))
    
    
    #-- CORRECT ACTUATOR POSITION --#
    
    #1. Retract actuator
    dcMotor.setTargetVelocity(-velocity)
    
    #2. Check and correct extra pulses
    #WHILE extra pulses still have not been corrected
    while extrapulse > 0:
        #Read digital input signal
        state = DigitalInput0.getState()
        
        #IF digital input is HIGH and pulse has not been recorded yet, THEN add pulse and change test variable.
        if (state == True) and (test == 0):
            extrapulse = extrapulse - 1
            pulse = pulse - 1
            test = 1
        #OTHERWISE, WHILE digital input is still HIGH (same hole on the encoder disc): wait and read digital input. ONCE digital input is not HIGH, change test variable.
        else:
            while state == True:
                state = DigitalInput0.getState()
            #Reset test variable
            test = 0
    
    #3. Print final pulse
    print("Final pulse: " + str(pulse))
    
    #4. Stop actuator
    dcMotor.setTargetVelocity(0)



    #Close channels
    DigitalInput0.close()
    dcMotor.close()

main()