class AzimuthController:
DIRECTION_GPIO = 38
PULSE_GPIO = 40
HOME_GPIO = 22
MICROSTEPS = 400
GEAR_RATIO = 48
LEFT_DIRECTION = True
RIGHT_DIRECTION = not LEFT_DIRECTION
HOMING_DIRECTION = LEFT_DIRECTION
BACKLASH_STEPS = 12
def __init__(self):
GPIO.setup(self.HOME_GPIO, GPIO.IN, pull_up_down = GPIO.PUD_UP)
self.__stepper = Stepper(self.MICROSTEPS * self.GEAR_RATIO, self.DIRECTION_GPIO, self.PULSE_GPIO, self.BACKLASH_STEPS)
steps = 0
while self.is_home():
self.__stepper.pulse(self.HOMING_DIRECTION)
steps += 1
if (steps > self.total_steps()):
raise ValueError("Cannot home the azimuth stepper. It is likely not moving or the sensor is broken.")
while not self.is_home():
self.__stepper.pulse(self.HOMING_DIRECTION)
steps += 1
if (steps > self.total_steps()):
raise ValueError("Cannot home the azimuth stepper. It is likely not moving or the sensor is broken.")
self.__stepper.reset_position()
def is_home(self):
return not GPIO.input(self.HOME_GPIO)
def position(self):
return self.__stepper.position()
def total_steps(self):
return self.__stepper.total_steps()
def move_left(self, steps):
return self.move(self.LEFT_DIRECTION, steps)
def move_right(self, steps):
return self.move(self.RIGHT_DIRECTION, steps)
def move(self, direction, steps):
self.__stepper.move(direction, steps)
return True
def move_to(self, position, max_steps = sys.maxint):
if position < 0 or position >= self.total_steps():
raise ValueError("Invalid position")
steps_from_left = (position - self.position()) % self.total_steps()
steps_from_right = (self.position() - position) % self.total_steps()
if steps_from_left <= steps_from_right:
self.move(self.LEFT_DIRECTION, min(steps_from_left, max_steps))
return steps_from_left <= max_steps
else:
self.move(self.RIGHT_DIRECTION, min(steps_from_right, max_steps))
return steps_from_right <= max_steps
class ElevationController:
DIRECTION_GPIO = 36
PULSE_GPIO = 32
# There are ~150 degrees between the two home sensors
HOME_DOWN_GPIO = 24
HOME_UP_GPIO = 26
MICROSTEPS = 400
GEAR_RATIO = 48
DOWN_DIRECTION = True
UP_DIRECTION = not DOWN_DIRECTION
BACKLASH_STEPS = 12
def __init__(self):
GPIO.setup(self.HOME_DOWN_GPIO, GPIO.IN, pull_up_down = GPIO.PUD_UP)
GPIO.setup(self.HOME_UP_GPIO, GPIO.IN, pull_up_down = GPIO.PUD_UP)
self.__stepper = Stepper(self.MICROSTEPS * self.GEAR_RATIO, self.DIRECTION_GPIO, self.PULSE_GPIO, self.BACKLASH_STEPS)
steps = 0
while self.is_home_down():
self.__stepper.pulse(self.UP_DIRECTION)
steps += 1
if (steps > self.__stepper.total_steps()):
raise ValueError("Cannot home the elevation stepper. It is likely not moving or the sensor is broken.")
while not self.is_home_down():
self.__stepper.pulse(self.DOWN_DIRECTION)
steps += 1
if (steps > self.__stepper.total_steps()):
raise ValueError("Cannot home the elevation stepper. It is likely not moving or the sensor is broken.")
steps = 0
self.__amplitude = 0
while not self.is_home_up():
self.__stepper.pulse(self.UP_DIRECTION)
steps += 1
self.__amplitude += 1
if (steps > self.__stepper.total_steps()):
raise ValueError("Cannot home the elevation stepper. It is likely not moving or the sensor is broken.")
self.__stepper.reset_position()
def is_home(self):
return self.is_home_down() or self.is_home_up()
def is_home_down(self):
return not GPIO.input(self.HOME_DOWN_GPIO)
def is_home_up(self):
return not GPIO.input(self.HOME_UP_GPIO)
def position(self):
position = float(self.__stepper.position()) / self.amplitude()
if position < 0 or position > 1:
raise ValueError("Invalid position about to be returned: " + position)
return position
def amplitude(self):
return self.__amplitude
def move_to(self, percentage_amplitude, max_delta = 1.0):
if percentage_amplitude < 0 or percentage_amplitude > 1:
raise ValueError("Percentage of amplitude must be between 0 and 1: " + str(percentage_amplitude))
steps = int((percentage_amplitude - self.position()) * self.amplitude())
max_steps = int(max_delta * self.amplitude())
direction = self.UP_DIRECTION if steps < 0 else self.DOWN_DIRECTION
self.__stepper.move(direction, min(abs(steps), max_steps))
return abs(steps) <= max_steps
