Hi everyone, thanks for your support - I modified my code for single phase / wave drive sequencing and this has totally fixed the problem, the motors hardly get luke warm now under constant use and I can even touch the heatsink on the L298N boards (not recommended by the way, I cooked the nerve endings in my fingers a long time ago
Sorry it took so long to get round to it, but this is the current instance of my code which includes the Pi Camera, a 4x4 keypad for control and has a basic implementation of the LSM303 accelerometer/magnetometer which doesn't do anything but spit out fairly useless numbers at present - I hope this maybe of some use to someone:
Code: Select all
# AutoTelescope by Aidan Taylor
# Move a telescope with 2 stepper motors
# Includes piCamera, Keypad Controls and LSM303 sensor for positioning
# Please note will run in Python 2 only
# include the following libraries
from picamera import PiCamera
import RPi.GPIO as GPIO
import Adafruit_LSM303
import time
# create Camera instance
camera = PiCamera() #activate the camera
camera.hflip = True
# create LSM303 instance
lsm303 = Adafruit_LSM303.LSM303()
#GPIO main setup
GPIO.setmode(GPIO.BOARD)
GPIO.setwarnings(False)
#Stepper GPIO
delay = 0.06 #sets how fast the steppers can sequence
steps = 100 #only used to test the steppers now
azCoilA1Pin = 11
azCoilA2Pin = 12
azCoilB1Pin = 13
azCoilB2Pin = 15
alCoilA1Pin = 16
alCoilA2Pin = 18
alCoilB1Pin = 19
alCoilB2Pin = 21
GPIO.setup(azCoilA1Pin, GPIO.OUT)
GPIO.setup(azCoilA2Pin, GPIO.OUT)
GPIO.setup(azCoilB1Pin, GPIO.OUT)
GPIO.setup(azCoilB2Pin, GPIO.OUT)
GPIO.setup(alCoilA1Pin, GPIO.OUT)
GPIO.setup(alCoilA2Pin, GPIO.OUT)
GPIO.setup(alCoilB1Pin, GPIO.OUT)
GPIO.setup(alCoilB2Pin, GPIO.OUT)
stepAzNum = 0
stepAlNum = 0
#Keypad GPIO
rowPins = [31,32,33,35]
colPins = [36,37,38,40]
GPIO.setup(40, GPIO.OUT)
GPIO.setup(38, GPIO.OUT)
GPIO.setup(37, GPIO.OUT)
GPIO.setup(36, GPIO.OUT)
GPIO.setup(31, GPIO.IN, pull_up_down=GPIO.PUD_UP)
GPIO.setup(32, GPIO.IN, pull_up_down=GPIO.PUD_UP)
GPIO.setup(33, GPIO.IN, pull_up_down=GPIO.PUD_UP)
GPIO.setup(35, GPIO.IN, pull_up_down=GPIO.PUD_UP)
digits = [["1","2","3","A"],
["4","5","6","B"],
["7","8","9","C"],
["*","0","#","D"]]
keyLatch = [[0,0,0,0],
[0,0,0,0],
[0,0,0,0],
[0,0,0,0]]
key = 0
lastKey = 0
keyMode = 0
#Controls to switch the stepper coils
def setAzStep(w1, w2, w3, w4):
GPIO.output(azCoilA1Pin, w1)
GPIO.output(azCoilA2Pin, w2)
GPIO.output(azCoilB1Pin, w3)
GPIO.output(azCoilB2Pin, w4)
def setAlStep(w1, w2, w3, w4):
GPIO.output(alCoilA1Pin, w1)
GPIO.output(alCoilA2Pin, w2)
GPIO.output(alCoilB1Pin, w3)
GPIO.output(alCoilB2Pin, w4)
#Controls to move the steppers backwards and forwards
def azForward():
global stepAzNum
stepAzNum = stepAzNum +1
if(stepAzNum <= 3):
if(stepAzNum == 1):
setAzStep(0,0,1,0)
time.sleep(delay)
if(stepAzNum == 2):
setAzStep(0,1,0,0)
time.sleep(delay)
if(stepAzNum == 3):
setAzStep(0,0,0,1)
time.sleep(delay)
else:
stepAzNum = 0
setAzStep(1,0,0,0)
time.sleep(delay)
def azBackward():
global stepAzNum
stepAzNum = stepAzNum -1
if(stepAzNum >= 0):
if(stepAzNum == 0):
setAzStep(1,0,0,0)
time.sleep(delay)
if(stepAzNum == 1):
setAzStep(0,0,1,0)
time.sleep(delay)
if(stepAzNum == 2):
setAzStep(0,1,0,0)
time.sleep(delay)
else:
stepAzNum = 3
setAzStep(0,0,0,1)
time.sleep(delay)
def alForward():
global stepAlNum
stepAlNum = stepAlNum +1
if(stepAlNum <= 3):
if(stepAlNum == 1):
setAlStep(0,0,1,0)
time.sleep(delay)
if(stepAlNum == 2):
setAlStep(0,1,0,0)
time.sleep(delay)
if(stepAlNum == 3):
setAlStep(0,0,0,1)
time.sleep(delay)
else:
stepAlNum = 0
setAlStep(1,0,0,0)
time.sleep(delay)
def alBackward():
global stepAlNum
stepAlNum = stepAlNum -1
if(stepAlNum >= 0):
if(stepAlNum == 0):
setAlStep(1,0,0,0)
time.sleep(delay)
if(stepAlNum == 1):
setAlStep(0,0,1,0)
time.sleep(delay)
if(stepAlNum == 2):
setAlStep(0,1,0,0)
time.sleep(delay)
else:
stepAlNum = 3
setAlStep(0,0,0,1)
time.sleep(delay)
#Used to test the steppers
def stepTest():
time.sleep(2)
for i in range(0, steps):
azForward()
time.sleep(2)
for i in range(0, steps):
azBackward()
time.sleep(2)
for i in range(0, steps):
alForward()
time.sleep(2)
for i in range(0, steps):
alBackward()
time.sleep(2)
#Scan the KeyPad
def controls():
global keyLatch
global key
#For Loop polls columns to check pressed rows
for col in range(0, 4):
GPIO.output(colPins[col],0)
time.sleep(0.001)
for row in range(0, 4):
inputState = GPIO.input(rowPins[row])
# print("col: ",col, "row: ",row)
if inputState == False and keyLatch[row][col] == False:
keyLatch[row][col] = True
key = (digits[row][col])
#print(digits[row][col]) #uncomment to debug
time.sleep(0.001)
elif inputState == True and keyLatch[row][col] == True:
keyLatch[row][col] = False
key = "z"
GPIO.output(colPins[col],1)
time.sleep(0.001)
def freeMove():
global keyLatch
global key
#For Loop polls columns to check pressed rows
for col in range(0, 4):
GPIO.output(colPins[col],0)
time.sleep(0.001)
for row in range(0, 4):
inputState = GPIO.input(rowPins[row])
# print("col: ",col, "row: ",row)
if inputState == False:
key = (digits[row][col])
#print(digits[row][col]) #uncomment to debug
time.sleep(0.001)
GPIO.output(colPins[col],1)
time.sleep(0.001)
# MAIN PROGRAM STARTS HERE
print("Program Starting")
#Unlock the steppers
setAzStep(0,0,0,0)
setAlStep(0,0,0,0)
print("Position telescope and press return/enter to start")
raw_input()
azForward()
alForward()
print("Press 2,6,8,4 to move, B and C for camera * to test, D to quit")
while True:
accel, mag = lsm303.read()
accel_x, accel_y, accel_z = accel
mag_x, mag_z, mag_y = mag
if keyMode == 1:
camera.annotate_text = 'FREEMOVE Accel X={0}, Accel Y={1}, Accel Z={2}, Mag X={3}, Mag Y={4}, Mag Z={5}'.format(
accel_x, accel_y, accel_z, mag_x, mag_y, mag_z)
else:
camera.annotate_text = 'Accel X={0}, Accel Y={1}, Accel Z={2}, Mag X={3}, Mag Y={4}, Mag Z={5}'.format(
accel_x, accel_y, accel_z, mag_x, mag_y, mag_z)
if keyMode == 0:
controls()
if key != lastKey:
lastKey = key
#print(key)
if(key == "2"):
alBackward()
elif(key == "8"):
alForward()
elif(key == "4"):
azForward()
elif(key == "6"):
azBackward()
elif(key == "*"):
stepTest()
elif(key == "B"):
camera.stop_preview()
print("Camera Exit")
elif(key == "C"):
camera.start_preview()
camera.vflip = True
camera.crop = (0.25, 0.25, 0.5, 0.5) # This line crops the camera but reduces resolution
elif(key == "#"):
print('Accel X={0}, Accel Y={1}, Accel Z={2}, Mag X={3}, Mag Y={4}, Mag Z={5}'.format(
accel_x, accel_y, accel_z, mag_x, mag_y, mag_z))
elif(key == "A"):
print("Free Move")
time.sleep(1)
keyMode = 1
key = "z"
elif(key == "D"):
camera.stop_preview()
print("Now Quitting, support Telescope")
time.sleep(5)
setAlStep(0,0,0,0)
setAzStep(0,0,0,0)
print("Finished")
break
else:
freeMove()
if(key == "2"):
alBackward()
key = "z"
elif(key == "8"):
alForward()
key = "z"
elif(key == "4"):
azForward()
key = "z"
elif(key == "6"):
azBackward()
key = "z"
elif(key == "A"):
print("Ending Free Move")
time.sleep(1)
keyMode = 0
- however, I didn't know about acceleration so I will read up on that thankyou!! 
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