class PIDController(threading.Thread):
"""
Class to operate discrete PID controller
"""
def __init__(self, ready, logger, pid_id):
threading.Thread.__init__(self)
self.thread_startup_timer = timeit.default_timer()
self.thread_shutdown_timer = 0
self.ready = ready
self.logger = logger
self.pid_id = pid_id
self.control = DaemonControl()
with session_scope(MYCODO_DB_PATH) as new_session:
pid = new_session.query(PID).filter(PID.id == self.pid_id).first()
self.sensor_id = pid.sensor_id
self.measure_type = pid.measure_type
self.method_id = pid.method_id
self.direction = pid.direction
self.raise_relay_id = pid.raise_relay_id
self.raise_min_duration = pid.raise_min_duration
self.raise_max_duration = pid.raise_max_duration
self.lower_relay_id = pid.lower_relay_id
self.lower_min_duration = pid.lower_min_duration
self.lower_max_duration = pid.lower_max_duration
self.Kp = pid.p
self.Ki = pid.i
self.Kd = pid.d
self.Integrator_min = pid.integrator_min
self.Integrator_max = pid.integrator_max
self.measure_interval = pid.period
self.default_set_point = pid.setpoint
self.set_point = pid.setpoint
sensor = new_session.query(Sensor).filter(Sensor.id == self.sensor_id).first()
self.sensor_duration = sensor.period
self.Derivator = 0
self.Integrator = 0
self.error = 0.0
self.P_value = None
self.I_value = None
self.D_value = None
self.raise_seconds_on = 0
self.timer = t.time()+self.measure_interval
# Check if a method is set for this PID
if self.method_id:
with session_scope(MYCODO_DB_PATH) as new_session:
method = new_session.query(Method)
method = method.filter(Method.method_id == self.method_id)
method = method.filter(Method.method_order == 0).first()
self.method_type = method.method_type
self.method_start_time = method.start_time
if self.method_type == 'Duration':
if self.method_start_time == 'Ended':
# Method has ended and hasn't been instructed to begin again
pass
elif self.method_start_time == 'Ready' or self.method_start_time == None:
# Method has been instructed to begin
with session_scope(MYCODO_DB_PATH) as db_session:
mod_method = db_session.query(Method)
mod_method = mod_method.filter(Method.method_id == self.method_id)
mod_method = mod_method.filter(Method.method_order == 0).first()
mod_method.start_time = datetime.datetime.now()
self.method_start_time = mod_method.start_time
db_session.commit()
else:
# Method neither instructed to begin or not to
# Likely there was a daemon restart ot power failure
# Resume method with saved start_time
self.method_start_time = datetime.datetime.strptime(
self.method_start_time, '%Y-%m-%d %H:%M:%S.%f')
self.logger.warning("[PID {}] Resuming method {} started at {}".format(
self.pid_id, self.method_id, self.method_start_time))
def run(self):
try:
self.running = True
self.logger.info("[PID {}] Activated in {:.1f} ms".format(
self.pid_id,
(timeit.default_timer()-self.thread_startup_timer)*1000))
self.ready.set()
while (self.running):
if t.time() > self.timer:
self.timer = self.timer+self.measure_interval
self.get_last_measurement()
self.manipulate_relays()
t.sleep(0.1)
if self.raise_relay_id:
self.control.relay_off(self.raise_relay_id)
if self.lower_relay_id:
self.control.relay_off(self.lower_relay_id)
self.running = False
self.logger.info("[PID {}] Deactivated in {:.1f} ms".format(
self.pid_id,
(timeit.default_timer()-self.thread_shutdown_timer)*1000))
except Exception as except_msg:
self.logger.exception("[PID {}] Run Error: Up ID {}, Down ID "
"{}: {}".format(self.pid_id,
self.raise_relay_id,
self.lower_relay_id,
except_msg))
def update(self, current_value):
"""
Calculate PID output value from reference input and feedback
:return: Manipulated, or control, variable. This is the PID output.
:rtype: float
:param current_value: The input, or process, variable (the actual
measured condition by the sensor)
:type current_value: float
"""
self.error = self.set_point - current_value
# Calculate P-value
self.P_value = self.Kp * self.error
# Calculate I-value
self.Integrator += self.error
# First method for managing Integrator
if self.Integrator > self.Integrator_max:
self.Integrator = self.Integrator_max
elif self.Integrator < self.Integrator_min:
self.Integrator = self.Integrator_min
# Second method for regulating Integrator
# if self.measure_interval is not None:
# if self.Integrator * self.Ki > self.measure_interval:
# self.Integrator = self.measure_interval / self.Ki
# elif self.Integrator * self.Ki < -self.measure_interval:
# self.Integrator = -self.measure_interval / self.Ki
self.I_value = self.Integrator * self.Ki
# Calculate D-value
self.D_value = self.Kd * (self.error - self.Derivator)
self.Derivator = self.error
# Produce output form P, I, and D values
PID = self.P_value + self.I_value + self.D_value
return PID
def get_last_measurement(self):
"""
Retrieve the latest sensor measurement from InfluxDB
:rtype: None
"""
self.last_measurement_success = False
# Get latest measurement (from within the past minute) from influxdb
try:
if self.sensor_duration < 60:
duration = 60
else:
duration = int(self.sensor_duration*1.5)
self.last_measurement = read_last_influxdb(
INFLUXDB_HOST,
INFLUXDB_PORT,
INFLUXDB_USER,
INFLUXDB_PASSWORD,
INFLUXDB_DATABASE,
self.sensor_id,
self.measure_type,
duration)
if self.last_measurement:
measurement_list = list(self.last_measurement.get_points(
measurement=self.measure_type))
self.last_time = measurement_list[0]['time']
self.last_measurement = measurement_list[0]['value']
utc_dt = datetime.datetime.strptime(self.last_time.split(".")[0], '%Y-%m-%dT%H:%M:%S')
utc_timestamp = calendar.timegm(utc_dt.timetuple())
local_timestamp = str(datetime.datetime.fromtimestamp(utc_timestamp))
self.logger.debug("[PID {}] Latest {}: {} @ {}".format(
self.pid_id, self.measure_type,
self.last_measurement, local_timestamp))
self.last_measurement_success = True
else:
self.logger.warning("[PID {}] No data returned "
"from influxdb".format(self.pid_id))
except Exception as except_msg:
self.logger.exception("[PID {}] Failed to read "
"measurement from the influxdb "
"database: {}".format(self.pid_id,
except_msg))
def manipulate_relays(self):
"""
Activate a relay based on PID output (control variable) and whether
the manipulation directive is to raise, lower, or both.
:rtype: None
"""
# If there was a measurement able to be retrieved from
# influxdb database that was entered within the past minute
if self.last_measurement_success:
# Update setpoint if a method is selected
if self.method_id != '':
self.calculate_method_setpoint(self.method_id)
self.addSetpointInfluxdb(self.pid_id, self.set_point)
# Update PID and get control variable
self.control_variable = self.update(self.last_measurement)
#
# PID control variable positive to raise environmental condition
#
if self.direction in ['raise', 'both'] and self.raise_relay_id:
if self.control_variable > 0:
# Ensure the relay on duration doesn't exceed the set maximum
if (self.raise_max_duration and
self.control_variable > self.raise_max_duration):
self.raise_seconds_on = self.raise_max_duration
else:
self.raise_seconds_on = float("{0:.2f}".format(self.control_variable))
# Turn off lower_relay if active, because we're now raising
if self.lower_relay_id:
with session_scope(MYCODO_DB_PATH) as new_session:
relay = new_session.query(Relay).filter(
Relay.id == self.lower_relay_id).first()
if relay.is_on():
self.control.relay_off(self.lower_relay_id)
if self.raise_seconds_on > self.raise_min_duration:
# Activate raise_relay for a duration
self.logger.debug("[PID {}] Setpoint: {} "
"Output: {} to relay {}".format(
self.pid_id,
self.set_point,
self.control_variable,
self.raise_relay_id))
self.control.relay_on(self.raise_relay_id,
self.raise_seconds_on)
else:
self.control.relay_off(self.raise_relay_id)
#
# PID control variable negative to lower environmental condition
#
if self.direction in ['lower', 'both'] and self.lower_relay_id:
if self.control_variable < 0:
# Ensure the relay on duration doesn't exceed the set maximum
if (self.lower_max_duration and
abs(self.control_variable) > self.lower_max_duration):
self.lower_seconds_on = self.lower_max_duration
else:
self.lower_seconds_on = abs(float("{0:.2f}".format(self.control_variable)))
# Turn off raise_relay if active, because we're now lowering
if self.raise_relay_id:
with session_scope(MYCODO_DB_PATH) as new_session:
relay = new_session.query(Relay).filter(
Relay.id == self.raise_relay_id).first()
if relay.is_on():
self.control.relay_off(self.raise_relay_id)
if self.lower_seconds_on > self.lower_min_duration:
# Activate lower_relay for a duration
self.logger.debug("[PID {}] Setpoint: {} "
"Output: {} to relay {}".format(
self.pid_id,
self.set_point,
self.control_variable,
self.lower_relay_id))
self.control.relay_on(self.lower_relay_id,
self.lower_seconds_on)
else:
self.control.relay_off(self.lower_relay_id)
else:
if self.direction in ['raise', 'both'] and self.raise_relay_id:
self.control.relay_off(self.raise_relay_id)
if self.direction in ['lower', 'both'] and self.lower_relay_id:
self.control.relay_off(self.lower_relay_id)
def calculate_method_setpoint(self, method_id):
with session_scope(MYCODO_DB_PATH) as new_session:
method = new_session.query(Method)
new_session.expunge_all()
new_session.close()
method_key = method.filter(Method.method_id == method_id)
method_key = method_key.filter(Method.method_order == 0).first()
method = method.filter(Method.method_id == method_id)
method = method.filter(Method.relay_id == None)
method = method.filter(Method.method_order > 0)
method = method.order_by(Method.method_order.asc()).all()
now = datetime.datetime.now()
# Calculate where the current time/date is within the time/date method
if method_key.method_type == 'Date':
for each_method in method:
start_time = datetime.datetime.strptime(each_method.start_time, '%Y-%m-%d %H:%M:%S')
end_time = end_time = datetime.datetime.strptime(each_method.end_time, '%Y-%m-%d %H:%M:%S')
if start_time < now < end_time:
start_setpoint = each_method.start_setpoint
if each_method.end_setpoint:
end_setpoint = each_method.end_setpoint
else:
end_setpoint = each_method.start_setpoint
setpoint_diff = abs(end_setpoint-start_setpoint)
total_seconds = (end_time-start_time).total_seconds()
part_seconds = (now-start_time).total_seconds()
percent_total = part_seconds/total_seconds
if start_setpoint < end_setpoint:
new_setpoint = start_setpoint+(setpoint_diff*percent_total)
else:
new_setpoint = start_setpoint-(setpoint_diff*percent_total)
self.logger.debug("[Method] Start: {} End: {}".format(
start_time, end_time))
self.logger.debug("[Method] Start: {} End: {}".format(
start_setpoint, end_setpoint))
self.logger.debug("[Method] Total: {} Part total: {} ({}%)".format(
total_seconds, part_seconds, percent_total))
self.logger.debug("[Method] New Setpoint: {}".format(
new_setpoint))
self.set_point = new_setpoint
return 0
# Calculate where the current Hour:Minute:Seconds is within the Daily method
elif method_key.method_type == 'Daily':
daily_now = datetime.datetime.now().strftime('%H:%M:%S')
daily_now = datetime.datetime.strptime(str(daily_now), '%H:%M:%S')
for each_method in method:
start_time = datetime.datetime.strptime(each_method.start_time, '%H:%M:%S')
end_time = end_time = datetime.datetime.strptime(each_method.end_time, '%H:%M:%S')
if start_time < daily_now < end_time:
start_setpoint = each_method.start_setpoint
if each_method.end_setpoint:
end_setpoint = each_method.end_setpoint
else:
end_setpoint = each_method.start_setpoint
setpoint_diff = abs(end_setpoint-start_setpoint)
total_seconds = (end_time-start_time).total_seconds()
part_seconds = (daily_now-start_time).total_seconds()
percent_total = part_seconds/total_seconds
if start_setpoint < end_setpoint:
new_setpoint = start_setpoint+(setpoint_diff*percent_total)
else:
new_setpoint = start_setpoint-(setpoint_diff*percent_total)
self.logger.debug("[Method] Start: {} End: {}".format(
start_time.strftime('%H:%M:%S'), end_time.strftime('%H:%M:%S')))
self.logger.debug("[Method] Start: {} End: {}".format(
start_setpoint, end_setpoint))
self.logger.debug("[Method] Total: {} Part total: {} ({}%)".format(
total_seconds, part_seconds, percent_total))
self.logger.debug("[Method] New Setpoint: {}".format(
new_setpoint))
self.set_point = new_setpoint
return 0
# Calculate sine y-axis value from the x-axis (seconds of the day)
elif method_key.method_type == 'DailySine':
new_setpoint = sine_wave_y_out(method_key.amplitude,
method_key.frequency,
method_key.shift_angle,
method_key.shift_y)
self.set_point = new_setpoint
return 0
# Calculate Bezier curve y-axis value from the x-axis (seconds of the day)
elif method_key.method_type == 'DailyBezier':
new_setpoint = bezier_curve_y_out(method_key.shift_angle,
(method_key.x0, method_key.y0),
(method_key.x1, method_key.y1),
(method_key.x2, method_key.y2),
(method_key.x3, method_key.y3))
self.set_point = new_setpoint
return 0
# Calculate the duration in the method based on self.method_start_time
elif method_key.method_type == 'Duration' and self.method_start_time != 'Ended':
seconds_from_start = (now-self.method_start_time).total_seconds()
total_sec = 0
previous_total_sec = 0
for each_method in method:
total_sec += each_method.duration_sec
if previous_total_sec <= seconds_from_start < total_sec:
row_start_time = float(self.method_start_time.strftime('%s'))+previous_total_sec
row_since_start_sec = (now-(self.method_start_time+datetime.timedelta(0, previous_total_sec))).total_seconds()
percent_row = row_since_start_sec/each_method.duration_sec
start_setpoint = each_method.start_setpoint
if each_method.end_setpoint:
end_setpoint = each_method.end_setpoint
else:
end_setpoint = each_method.start_setpoint
setpoint_diff = abs(end_setpoint-start_setpoint)
if start_setpoint < end_setpoint:
new_setpoint = start_setpoint+(setpoint_diff*percent_row)
else:
new_setpoint = start_setpoint-(setpoint_diff*percent_row)
self.logger.debug("[Method] Start: {} Seconds Since: {}".format(
self.method_start_time, seconds_from_start))
self.logger.debug("[Method] Start time of row: {}".format(
datetime.datetime.fromtimestamp(row_start_time)))
self.logger.debug("[Method] Sec since start of row: {}".format(
row_since_start_sec))
self.logger.debug("[Method] Percent of row: {}".format(
percent_row))
self.logger.debug("[Method] New Setpoint: {}".format(
new_setpoint))
self.set_point = new_setpoint
return 0
previous_total_sec = total_sec
# Duration method has ended, reset start_time locally and in DB
if self.method_start_time:
with session_scope(MYCODO_DB_PATH) as db_session:
mod_method = db_session.query(Method).filter(
Method.method_id == self.method_id)
mod_method = mod_method.filter(Method.method_order == 0).first()
mod_method.start_time = 'Ended'
db_session.commit()
self.method_start_time = 'Ended'
# Setpoint not needing to be calculated, use default setpoint
self.set_point = self.default_set_point
def addSetpointInfluxdb(self, pid_id, setpoint):
"""
Add a setpoint entry to InfluxDB
:rtype: None
"""
write_db = threading.Thread(
target=write_influxdb_value,
args=(self.logger, INFLUXDB_HOST,
INFLUXDB_PORT, INFLUXDB_USER,
INFLUXDB_PASSWORD, INFLUXDB_DATABASE,
'pid', pid_id, 'setpoint', setpoint,))
write_db.start()
def setPoint(self, set_point):
"""Initilize the setpoint of PID"""
self.set_point = set_point
self.Integrator = 0
self.Derivator = 0
def setIntegrator(self, Integrator):
"""Set the Integrator of the controller"""
self.Integrator = Integrator
def setDerivator(self, Derivator):
"""Set the Derivator of the controller"""
self.Derivator = Derivator
def setKp(self, P):
"""Set Kp gain of the controller"""
self.Kp = P
def setKi(self, I):
"""Set Ki gain of the controller"""
self.Ki = I
def setKd(self, D):
"""Set Kd gain of the controller"""
self.Kd = D
def getPoint(self):
return self.set_point
def getError(self):
return self.error
def getIntegrator(self):
return self.Integrator
def getDerivator(self):
return self.Derivator
def isRunning(self):
return self.running
def stopController(self):
self.thread_shutdown_timer = timeit.default_timer()
self.running = False
# Unset method start time
if self.method_id:
with session_scope(MYCODO_DB_PATH) as db_session:
mod_method = db_session.query(Method)
mod_method = mod_method.filter(Method.method_id == self.method_id)
mod_method = mod_method.filter(Method.method_order == 0).first()
mod_method.start_time = 'Ended'
db_session.commit()
class PIDController(threading.Thread):
"""
Class to operate discrete PID controller
"""
def __init__(self, ready, pid_id):
threading.Thread.__init__(self)
self.logger = logging.getLogger("mycodo.pid_{id}".format(id=pid_id))
self.running = False
self.thread_startup_timer = timeit.default_timer()
self.thread_shutdown_timer = 0
self.ready = ready
self.pid_id = pid_id
self.pid_unique_id = db_retrieve_table_daemon(
PID, device_id=self.pid_id).unique_id
self.control = DaemonControl()
self.control_variable = 0.0
self.derivator = 0.0
self.integrator = 0.0
self.error = 0.0
self.P_value = None
self.I_value = None
self.D_value = None
self.set_point = 0.0
self.lower_seconds_on = 0.0
self.raise_seconds_on = 0.0
self.lower_duty_cycle = 0.0
self.raise_duty_cycle = 0.0
self.last_time = None
self.last_measurement = None
self.last_measurement_success = False
self.is_activated = None
self.is_held = None
self.is_paused = None
self.measurement = None
self.method_id = None
self.direction = None
self.raise_output_id = None
self.raise_min_duration = None
self.raise_max_duration = None
self.raise_min_off_duration = None
self.lower_output_id = None
self.lower_min_duration = None
self.lower_max_duration = None
self.lower_min_off_duration = None
self.Kp = None
self.Ki = None
self.Kd = None
self.integrator_min = None
self.integrator_max = None
self.period = None
self.max_measure_age = None
self.default_set_point = None
self.set_point = None
self.input_unique_id = None
self.input_duration = None
self.raise_output_type = None
self.lower_output_type = None
self.initialize_values()
self.timer = t.time() + self.period
# Check if a method is set for this PID
self.method_start_act = None
if self.method_id:
method = db_retrieve_table_daemon(Method, device_id=self.method_id)
method_data = db_retrieve_table_daemon(MethodData)
method_data = method_data.filter(
MethodData.method_id == self.method_id)
method_data_repeat = method_data.filter(
MethodData.duration_sec == 0).first()
pid = db_retrieve_table_daemon(PID, device_id=self.pid_id)
self.method_type = method.method_type
self.method_start_act = pid.method_start_time
self.method_start_time = None
self.method_end_time = None
if self.method_type == 'Duration':
if self.method_start_act == 'Ended':
# Method has ended and hasn't been instructed to begin again
pass
elif self.method_start_act == 'Ready' or self.method_start_act is None:
# Method has been instructed to begin
now = datetime.datetime.now()
self.method_start_time = now
if method_data_repeat and method_data_repeat.duration_end:
self.method_end_time = now + datetime.timedelta(
seconds=float(method_data_repeat.duration_end))
with session_scope(MYCODO_DB_PATH) as db_session:
mod_pid = db_session.query(PID)
mod_pid = mod_pid.filter(PID.id == self.pid_id).first()
mod_pid.method_start_time = self.method_start_time
mod_pid.method_end_time = self.method_end_time
db_session.commit()
else:
# Method neither instructed to begin or not to
# Likely there was a daemon restart ot power failure
# Resume method with saved start_time
self.method_start_time = datetime.datetime.strptime(
str(pid.method_start_time), '%Y-%m-%d %H:%M:%S.%f')
if method_data_repeat and method_data_repeat.duration_end:
self.method_end_time = datetime.datetime.strptime(
str(pid.method_end_time), '%Y-%m-%d %H:%M:%S.%f')
if self.method_end_time > datetime.datetime.now():
self.logger.warning(
"Resuming method {id}: started {start}, "
"ends {end}".format(
id=self.method_id,
start=self.method_start_time,
end=self.method_end_time))
else:
self.method_start_act = 'Ended'
else:
self.method_start_act = 'Ended'
def run(self):
try:
self.running = True
self.logger.info("Activated in {:.1f} ms".format(
(timeit.default_timer() - self.thread_startup_timer) * 1000))
if self.is_paused:
self.logger.info("Paused")
elif self.is_held:
self.logger.info("Held")
self.ready.set()
while self.running:
if (self.method_start_act == 'Ended'
and self.method_type == 'Duration'):
self.stop_controller(ended_normally=False,
deactivate_pid=True)
self.logger.warning(
"Method has ended. "
"Activate the PID controller to start it again.")
elif t.time() > self.timer:
# Ensure the timer ends in the future
while t.time() > self.timer:
self.timer = self.timer + self.period
# If PID is active, retrieve input measurement and update PID output
if self.is_activated and not self.is_paused:
self.get_last_measurement()
if self.last_measurement_success:
# Update setpoint using a method if one is selected
if self.method_id:
this_controller = db_retrieve_table_daemon(
PID, device_id=self.pid_id)
setpoint, ended = calculate_method_setpoint(
self.method_id, PID, this_controller,
Method, MethodData, self.logger)
if ended:
self.method_start_act = 'Ended'
if setpoint is not None:
self.set_point = setpoint
else:
self.set_point = self.default_set_point
write_setpoint_db = threading.Thread(
target=write_influxdb_value,
args=(
self.pid_unique_id,
'setpoint',
self.set_point,
))
write_setpoint_db.start()
# Update PID and get control variable
self.control_variable = self.update_pid_output(
self.last_measurement)
# If PID is active or on hold, activate outputs
if ((self.is_activated and not self.is_paused)
or (self.is_activated and self.is_held)):
self.manipulate_output()
t.sleep(0.1)
# Turn off output used in PID when the controller is deactivated
if self.raise_output_id and self.direction in ['raise', 'both']:
self.control.relay_off(self.raise_output_id,
trigger_conditionals=True)
if self.lower_output_id and self.direction in ['lower', 'both']:
self.control.relay_off(self.lower_output_id,
trigger_conditionals=True)
self.running = False
self.logger.info("Deactivated in {:.1f} ms".format(
(timeit.default_timer() - self.thread_shutdown_timer) * 1000))
except Exception as except_msg:
self.logger.exception("Run Error: {err}".format(err=except_msg))
def initialize_values(self):
"""Set PID parameters"""
pid = db_retrieve_table_daemon(PID, device_id=self.pid_id)
self.is_activated = pid.is_activated
self.is_held = pid.is_held
self.is_paused = pid.is_paused
self.method_id = pid.method_id
self.direction = pid.direction
self.raise_output_id = pid.raise_relay_id
self.raise_min_duration = pid.raise_min_duration
self.raise_max_duration = pid.raise_max_duration
self.raise_min_off_duration = pid.raise_min_off_duration
self.lower_output_id = pid.lower_relay_id
self.lower_min_duration = pid.lower_min_duration
self.lower_max_duration = pid.lower_max_duration
self.lower_min_off_duration = pid.lower_min_off_duration
self.Kp = pid.p
self.Ki = pid.i
self.Kd = pid.d
self.integrator_min = pid.integrator_min
self.integrator_max = pid.integrator_max
self.period = pid.period
self.max_measure_age = pid.max_measure_age
self.default_set_point = pid.setpoint
self.set_point = pid.setpoint
input_unique_id = pid.measurement.split(',')[0]
self.measurement = pid.measurement.split(',')[1]
input_dev = db_retrieve_table_daemon(Input, unique_id=input_unique_id)
self.input_unique_id = input_dev.unique_id
self.input_duration = input_dev.period
try:
self.raise_output_type = db_retrieve_table_daemon(
Output, device_id=self.raise_output_id).relay_type
except AttributeError:
self.raise_output_type = None
try:
self.lower_output_type = db_retrieve_table_daemon(
Output, device_id=self.lower_output_id).relay_type
except AttributeError:
self.lower_output_type = None
return "success"
def update_pid_output(self, current_value):
"""
Calculate PID output value from reference input and feedback
:return: Manipulated, or control, variable. This is the PID output.
:rtype: float
:param current_value: The input, or process, variable (the actual
measured condition by the input)
:type current_value: float
"""
self.error = self.set_point - current_value
# Calculate P-value
self.P_value = self.Kp * self.error
# Calculate I-value
self.integrator += self.error
# First method for managing integrator
if self.integrator > self.integrator_max:
self.integrator = self.integrator_max
elif self.integrator < self.integrator_min:
self.integrator = self.integrator_min
# Second method for regulating integrator
# if self.period is not None:
# if self.integrator * self.Ki > self.period:
# self.integrator = self.period / self.Ki
# elif self.integrator * self.Ki < -self.period:
# self.integrator = -self.period / self.Ki
self.I_value = self.integrator * self.Ki
# Calculate D-value
self.D_value = self.Kd * (self.error - self.derivator)
self.derivator = self.error
# Produce output form P, I, and D values
pid_value = self.P_value + self.I_value + self.D_value
return pid_value
def get_last_measurement(self):
"""
Retrieve the latest input measurement from InfluxDB
:rtype: None
"""
self.last_measurement_success = False
# Get latest measurement (from within the past minute) from influxdb
try:
if self.input_duration < 60:
duration = 60
else:
duration = int(self.input_duration * 1.5)
self.last_measurement = read_last_influxdb(self.input_unique_id,
self.measurement,
duration)
if self.last_measurement:
self.last_time = self.last_measurement[0]
self.last_measurement = self.last_measurement[1]
utc_dt = datetime.datetime.strptime(
self.last_time.split(".")[0], '%Y-%m-%dT%H:%M:%S')
utc_timestamp = calendar.timegm(utc_dt.timetuple())
local_timestamp = str(
datetime.datetime.fromtimestamp(utc_timestamp))
self.logger.debug("Latest {meas}: {last} @ {ts}".format(
meas=self.measurement,
last=self.last_measurement,
ts=local_timestamp))
if calendar.timegm(
t.gmtime()) - utc_timestamp > self.max_measure_age:
self.logger.error(
"Last measurement was {last_sec} seconds ago, however"
" the maximum measurement age is set to {max_sec}"
" seconds.".format(
last_sec=calendar.timegm(t.gmtime()) -
utc_timestamp,
max_sec=self.max_measure_age))
self.last_measurement_success = True
else:
self.logger.warning("No data returned from influxdb")
except requests.ConnectionError:
self.logger.error("Failed to read measurement from the "
"influxdb database: Could not connect.")
except Exception as except_msg:
self.logger.exception(
"Exception while reading measurement from the influxdb "
"database: {err}".format(err=except_msg))
def manipulate_output(self):
"""
Activate output based on PID control variable and whether
the manipulation directive is to raise, lower, or both.
:rtype: None
"""
# If the last measurement was able to be retrieved and was entered within the past minute
if self.last_measurement_success:
#
# PID control variable is positive, indicating a desire to raise
# the environmental condition
#
if self.direction in ['raise', 'both'] and self.raise_output_id:
if self.control_variable > 0:
# Turn off lower_output if active, because we're now raising
if (self.direction == 'both' and self.lower_output_id
and self.control.relay_state(
self.lower_output_id) != 'off'):
self.control.relay_off(self.lower_output_id)
# Determine if the output should be PWM or a duration
if self.raise_output_type == 'pwm':
self.raise_duty_cycle = float("{0:.1f}".format(
self.control_var_to_duty_cycle(
self.control_variable)))
# Ensure the duty cycle doesn't exceed the min/max
if (self.raise_max_duration and self.raise_duty_cycle >
self.raise_max_duration):
self.raise_duty_cycle = self.raise_max_duration
elif (self.raise_min_duration and
self.raise_duty_cycle < self.raise_min_duration):
self.raise_duty_cycle = self.raise_min_duration
self.logger.debug(
"Setpoint: {sp}, Control Variable: {cv}, Output: PWM output "
"{id} to {dc:.1f}%".format(
sp=self.set_point,
cv=self.control_variable,
id=self.raise_output_id,
dc=self.raise_duty_cycle))
# Activate pwm with calculated duty cycle
self.control.relay_on(self.raise_output_id,
duty_cycle=self.raise_duty_cycle)
pid_entry_value = self.control_var_to_duty_cycle(
abs(self.control_variable))
if self.control_variable < 0:
pid_entry_value = -pid_entry_value
self.write_pid_output_influxdb('duty_cycle',
pid_entry_value)
elif self.raise_output_type in [
'command', 'wired', 'wireless_433MHz_pi_switch'
]:
# Ensure the output on duration doesn't exceed the set maximum
if (self.raise_max_duration and self.control_variable >
self.raise_max_duration):
self.raise_seconds_on = self.raise_max_duration
else:
self.raise_seconds_on = float("{0:.2f}".format(
self.control_variable))
if self.raise_seconds_on > self.raise_min_duration:
# Activate raise_output for a duration
self.logger.debug(
"Setpoint: {sp} Output: {cv} to output "
"{id}".format(sp=self.set_point,
cv=self.control_variable,
id=self.raise_output_id))
self.control.relay_on(
self.raise_output_id,
duration=self.raise_seconds_on,
min_off=self.raise_min_off_duration)
self.write_pid_output_influxdb('pid_output',
self.control_variable)
else:
if self.raise_output_type == 'pwm':
self.control.relay_on(self.raise_output_id,
duty_cycle=0)
else:
self.control.relay_off(self.raise_output_id)
#
# PID control variable is negative, indicating a desire to lower
# the environmental condition
#
if self.direction in ['lower', 'both'] and self.lower_output_id:
if self.control_variable < 0:
# Turn off raise_output if active, because we're now raising
if (self.direction == 'both' and self.raise_output_id
and self.control.relay_state(
self.raise_output_id) != 'off'):
self.control.relay_off(self.raise_output_id)
# Determine if the output should be PWM or a duration
if self.lower_output_type == 'pwm':
self.lower_duty_cycle = float("{0:.1f}".format(
self.control_var_to_duty_cycle(
abs(self.control_variable))))
# Ensure the duty cycle doesn't exceed the min/max
if (self.lower_max_duration and self.lower_duty_cycle >
self.lower_max_duration):
self.lower_duty_cycle = self.lower_max_duration
elif (self.lower_min_duration and
self.lower_duty_cycle < self.lower_min_duration):
self.lower_duty_cycle = self.lower_min_duration
self.logger.debug(
"Setpoint: {sp}, Control Variable: {cv}, "
"Output: PWM output {id} to {dc:.1f}%".format(
sp=self.set_point,
cv=self.control_variable,
id=self.lower_output_id,
dc=self.lower_duty_cycle))
# Turn back negative for proper logging
self.lower_duty_cycle = -self.lower_duty_cycle
# Activate pwm with calculated duty cycle
self.control.relay_on(self.lower_output_id,
duty_cycle=self.lower_duty_cycle)
pid_entry_value = self.control_var_to_duty_cycle(
abs(self.control_variable))
pid_entry_value = -pid_entry_value
self.write_pid_output_influxdb('duty_cycle',
pid_entry_value)
elif self.lower_output_type in [
'command', 'wired', 'wireless_433MHz_pi_switch'
]:
# Ensure the output on duration doesn't exceed the set maximum
if (self.lower_max_duration
and abs(self.control_variable) >
self.lower_max_duration):
self.lower_seconds_on = self.lower_max_duration
else:
self.lower_seconds_on = float("{0:.2f}".format(
self.control_variable))
if abs(self.lower_seconds_on
) > self.lower_min_duration:
# Activate lower_output for a duration
self.logger.debug("Setpoint: {sp} Output: {cv} to "
"output {id}".format(
sp=self.set_point,
cv=self.control_variable,
id=self.lower_output_id))
self.control.relay_on(
self.lower_output_id,
duration=self.lower_seconds_on,
min_off=self.lower_min_off_duration)
self.write_pid_output_influxdb('pid_output',
self.control_variable)
else:
if self.lower_output_type == 'pwm':
self.control.relay_on(self.lower_output_id,
duty_cycle=0)
else:
self.control.relay_off(self.lower_output_id)
else:
if self.direction in ['raise', 'both'] and self.raise_output_id:
self.control.relay_off(self.raise_output_id)
if self.direction in ['lower', 'both'] and self.lower_output_id:
self.control.relay_off(self.lower_output_id)
def control_var_to_duty_cycle(self, control_variable):
# Convert control variable to duty cycle
if control_variable > self.period:
return 100.0
else:
return float((control_variable / self.period) * 100)
def write_pid_output_influxdb(self, pid_entry_type, pid_entry_value):
write_pid_out_db = threading.Thread(target=write_influxdb_value,
args=(
self.pid_unique_id,
pid_entry_type,
pid_entry_value,
))
write_pid_out_db.start()
def pid_mod(self):
if self.initialize_values():
return "success"
else:
return "error"
def pid_hold(self):
self.is_held = True
self.logger.info("Hold")
return "success"
def pid_pause(self):
self.is_paused = True
self.logger.info("Pause")
return "success"
def pid_resume(self):
self.is_activated = True
self.is_held = False
self.is_paused = False
self.logger.info("Resume")
return "success"
def set_setpoint(self, set_point):
""" Initilize the setpoint of PID """
self.set_point = set_point
self.integrator = 0
self.derivator = 0
def set_integrator(self, integrator):
""" Set the integrator of the controller """
self.integrator = integrator
def set_derivator(self, derivator):
""" Set the derivator of the controller """
self.derivator = derivator
def set_kp(self, p):
""" Set Kp gain of the controller """
self.Kp = p
def set_ki(self, i):
""" Set Ki gain of the controller """
self.Ki = i
def set_kd(self, d):
""" Set Kd gain of the controller """
self.Kd = d
def get_setpoint(self):
return self.set_point
def get_error(self):
return self.error
def get_integrator(self):
return self.integrator
def get_derivator(self):
return self.derivator
def is_running(self):
return self.running
def stop_controller(self, ended_normally=True, deactivate_pid=False):
self.thread_shutdown_timer = timeit.default_timer()
self.running = False
# Unset method start time
if self.method_id and ended_normally:
with session_scope(MYCODO_DB_PATH) as db_session:
mod_pid = db_session.query(PID).filter(
PID.id == self.pid_id).first()
mod_pid.method_start_time = 'Ended'
mod_pid.method_end_time = None
db_session.commit()
if deactivate_pid:
with session_scope(MYCODO_DB_PATH) as db_session:
mod_pid = db_session.query(PID).filter(
PID.id == self.pid_id).first()
mod_pid.is_activated = False
db_session.commit()
class PIDController(threading.Thread):
"""
Class to operate discrete PID controller
"""
def __init__(self, ready, logger, pid_id):
threading.Thread.__init__(self)
self.thread_startup_timer = timeit.default_timer()
self.thread_shutdown_timer = 0
self.ready = ready
self.logger = logger
self.pid_id = pid_id
self.control = DaemonControl()
with session_scope(MYCODO_DB_PATH) as new_session:
pid = new_session.query(PID).filter(PID.id == self.pid_id).first()
self.sensor_id = pid.sensor_id
self.measure_type = pid.measure_type
self.direction = pid.direction
self.raise_relay_id = pid.raise_relay_id
self.raise_min_duration = pid.raise_min_duration
self.raise_max_duration = pid.raise_max_duration
self.lower_relay_id = pid.lower_relay_id
self.lower_min_duration = pid.lower_min_duration
self.lower_max_duration = pid.lower_max_duration
self.Kp = pid.p
self.Ki = pid.i
self.Kd = pid.d
self.measure_interval = pid.period
self.default_set_point = pid.setpoint
self.set_point = pid.setpoint
with session_scope(MYCODO_DB_PATH) as new_session:
self.pidsetpoints = new_session.query(PIDSetpoints)
self.pidsetpoints = self.pidsetpoints.filter(PIDSetpoints.pid_id == self.pid_id)
self.pidsetpoints = self.pidsetpoints.order_by(PIDSetpoints.start_time.asc())
new_session.expunge_all()
new_session.close()
self.Derivator = 0
self.Integrator = 0
self.Integrator_max = 500
self.Integrator_min = -500
self.error = 0.0
self.P_value = None
self.I_value = None
self.D_value = None
self.raise_seconds_on = 0
self.timer = t.time() + self.measure_interval
def run(self):
try:
self.running = True
self.logger.info("[PID {}] Activated in {}ms".format(
self.pid_id,
(timeit.default_timer()-self.thread_startup_timer)*1000))
self.ready.set()
while (self.running):
if t.time() > self.timer:
self.timer = t.time() + self.measure_interval
self.get_last_measurement()
self.manipulate_relays()
t.sleep(0.1)
if self.raise_relay_id:
self.control.relay_off(self.raise_relay_id)
if self.lower_relay_id:
self.control.relay_off(self.lower_relay_id)
self.running = False
self.logger.info("[PID {}] Deactivated in {}ms".format(
self.pid_id,
(timeit.default_timer()-self.thread_shutdown_timer)*1000))
except Exception as except_msg:
self.logger.exception("[PID {}] Error: {}".format(self.pid_id,
except_msg))
def update(self, current_value):
"""
Calculate PID output value from reference input and feedback
:return: Manipulated, or control, variable. This is the PID output.
:rtype: float
:param current_value: The input, or process, variable (the actual
measured condition by the sensor)
:type current_value: float
"""
self.error = self.set_point - current_value
# Calculate P-value
self.P_value = self.Kp * self.error
# Calculate I-value
self.Integrator += self.error
# Old method for managing Integrator
# if self.Integrator > self.Integrator_max:
# self.Integrator = self.Integrator_max
# elif self.Integrator < self.Integrator_min:
# self.Integrator = self.Integrator_min
# New method for regulating Integrator
if self.measure_interval is not None:
if self.Integrator * self.Ki > self.measure_interval:
self.Integrator = self.measure_interval / self.Ki
elif self.Integrator * self.Ki < -self.measure_interval:
self.Integrator = -self.measure_interval / self.Ki
self.I_value = self.Integrator * self.Ki
# Calculate D-value
self.D_value = self.Kd * (self.error - self.Derivator)
self.Derivator = self.error
# Produce output form P, I, and D values
PID = self.P_value + self.I_value + self.D_value
return PID
def get_last_measurement(self):
"""
Retrieve the latest sensor measurement from InfluxDB
:rtype: None
"""
self.last_measurement_success = False
# Get latest measurement (from within the past minute) from influxdb
try:
self.last_measurement = read_last_influxdb(
INFLUXDB_HOST,
INFLUXDB_PORT,
INFLUXDB_USER,
INFLUXDB_PASSWORD,
INFLUXDB_DATABASE,
self.sensor_id,
self.measure_type)
if self.last_measurement:
measurement_list = list(self.last_measurement.get_points(
measurement=self.measure_type))
self.last_time = measurement_list[0]['time']
self.last_measurement = measurement_list[0]['value']
utc_dt = datetime.strptime(self.last_time.split(".")[0], '%Y-%m-%dT%H:%M:%S')
utc_timestamp = calendar.timegm(utc_dt.timetuple())
local_timestamp = str(datetime.fromtimestamp(utc_timestamp))
self.logger.debug("[PID {}] Latest {}: {} @ {}".format(
self.pid_id, self.measure_type,
self.last_measurement, local_timestamp))
self.last_measurement_success = True
else:
self.logger.warning("[PID {}] No data returned "
"from influxdb".format(self.pid_id))
except Exception as except_msg:
self.logger.exception("[PID {}] Failed to read "
"measurement from the influxdb "
"database: {}".format(self.pid_id,
except_msg))
def manipulate_relays(self):
"""
Activate a relay based on PID output (control variable) and whether
the manipulation directive is to raise, lower, or both.
:rtype: None
"""
# If there was a measurement able to be retrieved from
# influxdb database that was entered within the past minute
if self.last_measurement_success:
# Update setpoint if dynamic setpoints are enabled for this PID
# and the current time is within one of the set time spans
use_default_setpoint = True
for each_setpt in self.pidsetpoints:
if self.now_in_range(each_setpt.start_time,
each_setpt.end_time):
use_default_setpoint = False
self.calculate_new_setpoint(each_setpt.start_time,
each_setpt.end_time,
each_setpt.start_setpoint,
each_setpt.end_setpoint)
self.logger.debug("[PID {}] New setpoint: {}".format(self.pid_id, self.set_point))
if use_default_setpoint:
self.set_point = self.default_set_point
self.addSetpointInfluxdb(self.pid_id, self.set_point)
# Update PID and get control variable
self.control_variable = self.update(self.last_measurement)
#
# PID control variable positive to raise environmental condition
#
if self.direction in ['raise', 'both'] and self.raise_relay_id:
if self.control_variable > 0:
# Ensure the relay on duration doesn't exceed the set maximum
if (self.raise_max_duration and
self.control_variable > self.raise_max_duration):
self.raise_seconds_on = self.raise_max_duration
else:
self.raise_seconds_on = float("{0:.2f}".format(self.control_variable))
# Turn off lower_relay if active, because we're now raising
if self.lower_relay_id:
with session_scope(MYCODO_DB_PATH) as new_session:
relay = new_session.query(Relay).filter(
Relay.id == self.lower_relay_id).first()
if relay.is_on():
self.control.relay_off(self.lower_relay_id)
if self.raise_seconds_on > self.raise_min_duration:
# Activate raise_relay for a duration
self.logger.debug("[PID {}] Setpoint: {} "
"Output: {} to relay {}".format(
self.pid_id,
self.set_point,
self.control_variable,
self.raise_relay_id))
self.control.relay_on(self.raise_relay_id,
self.raise_seconds_on)
else:
self.control.relay_off(self.raise_relay_id)
#
# PID control variable negative to lower environmental condition
#
if self.direction in ['lower', 'both'] and self.lower_relay_id:
if self.control_variable < 0:
# Ensure the relay on duration doesn't exceed the set maximum
if (self.lower_max_duration and
abs(self.control_variable) > self.lower_max_duration):
self.lower_seconds_on = self.lower_max_duration
else:
self.lower_seconds_on = abs(float("{0:.2f}".format(self.control_variable)))
# Turn off raise_relay if active, because we're now lowering
if self.raise_relay_id:
with session_scope(MYCODO_DB_PATH) as new_session:
relay = new_session.query(Relay).filter(
Relay.id == self.raise_relay_id).first()
if relay.is_on():
self.control.relay_off(self.raise_relay_id)
if self.lower_seconds_on > self.lower_min_duration:
# Activate lower_relay for a duration
self.logger.debug("[PID {}] Setpoint: {} "
"Output: {} to relay {}".format(
self.pid_id,
self.set_point,
self.control_variable,
self.lower_relay_id))
self.control.relay_on(self.lower_relay_id,
self.lower_seconds_on)
else:
self.control.relay_off(self.lower_relay_id)
else:
if self.direction in ['raise', 'both'] and self.raise_relay_id:
self.control.relay_off(self.raise_relay_id)
if self.direction in ['lower', 'both'] and self.lower_relay_id:
self.control.relay_off(self.lower_relay_id)
def now_in_range(self, start_time, end_time):
"""
Check if the current time is between start_time and end_time
:return: 1 is within range, 0 if not within range
:rtype: int
"""
start_hour = int(start_time.split(":")[0])
start_min = int(start_time.split(":")[1])
end_hour = int(end_time.split(":")[0])
end_min = int(end_time.split(":")[1])
now_time = datetime.now().time()
now_time = now_time.replace(second=0, microsecond=0)
if ((start_hour < end_hour) or
(start_hour == end_hour and start_min < end_min)):
if now_time >= time(start_hour,start_min) and now_time <= time(end_hour,end_min):
return 1 # Yes now within range
else:
if now_time >= time(start_hour,start_min) or now_time <= time(end_hour,end_min):
return 1 # Yes now within range
return 0 # No now not within range
def calculate_new_setpoint(self, start_time, end_time, start_setpoint, end_setpoint):
"""
Calculate a dynamic setpoint that changes over time
The current time must fall between the start_time and end_time.
If there is only a start_setpoint, that is the only setpoint that can
be returned.
Based on where the current time falls between the start_time
and the end_time, a setpoint between the start_setpoint and
end_setpoint will be calculated.
For example, if the time range is 12:00 to 1:00, and the setPoint
range is 0 to 60, and the current time is 12:30, the calculated
setpoint will be 30.
:return: 0 if only a start setpoint is set, 1 if both start and end
setpoints are set and the value between has been calculated.
:rtype: int
:param start_time: The start hour and minute of the time range
:type start_time: str
:param end_time: The end hour and minute of the time range
:type end_time: str
:param start_setpoint: The start setpoint
:type start_setpoint: float
:param end_setpoint: The end setpoint
:type end_setpoint: float or None
"""
# Only a start_setpoint set for this time period
if end_setpoint is None:
self.set_point = start_setpoint
return 0
# Split hour and minute into separate integers
start_hour = int(start_time.split(":")[0])
start_min = int(start_time.split(":")[1])
end_hour = int(end_time.split(":")[0])
end_min = int(end_time.split(":")[1])
# Set the date and time format
date_format = "%d %H:%M" # Add day in case end time is the next day
# Convert string of 'day hour:minute' to actual date and time
start_time_formatted = datetime.strptime("1 "+start_time, date_format)
end_day_modifier = "1 " # End time is the same day
if (start_hour > end_hour or
(start_hour == end_hour and start_min > end_min)):
end_day_modifier = "2 " # End time is the next day
end_time_formatted = datetime.strptime(end_day_modifier+end_time, date_format)
# Total number of minute between start time and end time
diff = end_time_formatted-start_time_formatted
diff_min = diff.seconds/60
# Find the difference between setpoints
diff_setpoints = abs(end_setpoint-start_setpoint)
# Total number of minute between start time and now
now = datetime.now()
if now.hour > start_hour:
hours = now.hour-start_hour
elif now.hour < start_hour:
hours = now.hour+(24-start_hour)
elif now.hour == start_hour:
hours = 0
minutes = now.minute-start_min # May be negative
total_minutes = (hours*60)+minutes
# Based on the number of minutes between the start and end time and the
# minutes passed since the start time, calculate the new setpoint
mod_setpoint = total_minutes/float(diff_min/diff_setpoints)
if end_setpoint < start_setpoint:
# Setpoint decreases over duration
new_setpoint = float("{0:.2f}".format(start_setpoint-mod_setpoint))
else:
# Setpoint increases over duration
new_setpoint = float("{0:.2f}".format(start_setpoint+mod_setpoint))
self.set_point = new_setpoint
return 1
def addSetpointInfluxdb(self, pid_id, setpoint):
"""
Add a setpoint entry to InfluxDB
:rtype: None
"""
write_db = threading.Thread(
target=write_influxdb,
args=(self.logger, INFLUXDB_HOST,
INFLUXDB_PORT, INFLUXDB_USER,
INFLUXDB_PASSWORD, INFLUXDB_DATABASE,
'pid', pid_id, 'setpoint', setpoint,))
write_db.start()
def setPoint(self, set_point):
"""Initilize the setpoint of PID"""
self.set_point = set_point
self.Integrator = 0
self.Derivator = 0
def setIntegrator(self, Integrator):
"""Set the Integrator of the controller"""
self.Integrator = Integrator
def setDerivator(self, Derivator):
"""Set the Derivator of the controller"""
self.Derivator = Derivator
def setKp(self, P):
"""Set Kp gain of the controller"""
self.Kp = P
def setKi(self, I):
"""Set Ki gain of the controller"""
self.Ki = I
def setKd(self, D):
"""Set Kd gain of the controller"""
self.Kd = D
def getPoint(self):
return self.set_point
def getError(self):
return self.error
def getIntegrator(self):
return self.Integrator
def getDerivator(self):
return self.Derivator
def isRunning(self):
return self.running
def stopController(self):
self.thread_shutdown_timer = timeit.default_timer()
self.running = False
class PIDController(threading.Thread):
"""
Class to operate discrete PID controller
"""
def __init__(self, ready, pid_id):
threading.Thread.__init__(self)
self.logger = logging.getLogger("mycodo.pid_{id}".format(id=pid_id))
self.running = False
self.thread_startup_timer = timeit.default_timer()
self.thread_shutdown_timer = 0
self.ready = ready
self.pid_id = pid_id
self.control = DaemonControl()
self.initialize_values()
self.control_variable = 0
self.Derivator = 0
self.Integrator = 0
self.error = 0.0
self.P_value = None
self.I_value = None
self.D_value = None
self.set_point = 0
self.lower_seconds_on = 0
self.raise_seconds_on = 0
self.last_measurement_success = False
self.timer = t.time() + self.measure_interval
# Check if a method is set for this PID
if self.method_id:
method = db_retrieve_table(MYCODO_DB_PATH, Method)
method = method.filter(Method.method_id == self.method_id)
method = method.filter(Method.method_order == 0).first()
self.method_type = method.method_type
self.method_start_time = method.start_time
if self.method_type == 'Duration':
if self.method_start_time == 'Ended':
# Method has ended and hasn't been instructed to begin again
pass
elif self.method_start_time == 'Ready' or self.method_start_time is None:
# Method has been instructed to begin
with session_scope(MYCODO_DB_PATH) as db_session:
mod_method = db_session.query(Method)
mod_method = mod_method.filter(
Method.method_id == self.method_id)
mod_method = mod_method.filter(
Method.method_order == 0).first()
mod_method.start_time = datetime.datetime.now()
self.method_start_time = mod_method.start_time
db_session.commit()
else:
# Method neither instructed to begin or not to
# Likely there was a daemon restart ot power failure
# Resume method with saved start_time
self.method_start_time = datetime.datetime.strptime(
str(self.method_start_time), '%Y-%m-%d %H:%M:%S.%f')
self.logger.warning(
"Resuming method {id} started at {time}".format(
id=self.method_id, time=self.method_start_time))
def run(self):
try:
self.running = True
self.logger.info("Activated in {:.1f} ms".format(
(timeit.default_timer() - self.thread_startup_timer) * 1000))
if self.activated == 2:
self.logger.info("Paused")
elif self.activated == 3:
self.logger.info("Held")
self.ready.set()
while self.running:
if t.time() > self.timer:
self.timer = self.timer + self.measure_interval
# self.activated: 0=inactive, 1=active, 2=pause, 3=hold
# If active, retrieve sensor measurement and update PID output
if self.activated == 1:
self.get_last_measurement()
if self.last_measurement_success:
# Update setpoint if a method is selected
if self.method_id != '':
self.calculate_method_setpoint(self.method_id)
write_influxdb_setpoint(self.pid_id,
self.set_point)
# Update PID and get control variable
self.control_variable = self.update(
self.last_measurement)
# If active or on hold, activate relays
if self.activated in [1, 3]:
self.manipulate_relays()
t.sleep(0.1)
if self.raise_relay_id:
self.control.relay_off(self.raise_relay_id)
if self.lower_relay_id:
self.control.relay_off(self.lower_relay_id)
self.running = False
self.logger.info("Deactivated in {:.1f} ms".format(
(timeit.default_timer() - self.thread_shutdown_timer) * 1000))
except Exception as except_msg:
self.logger.exception("Run Error: {err}".format(err=except_msg))
def initialize_values(self):
"""Set PID parameters"""
pid = db_retrieve_table(MYCODO_DB_PATH, PID, device_id=self.pid_id)
sensor = db_retrieve_table(MYCODO_DB_PATH,
Sensor,
device_id=pid.sensor_id)
self.activated = pid.activated # 0=inactive, 1=active, 2=paused
self.sensor_id = pid.sensor_id
self.measure_type = pid.measure_type
self.method_id = pid.method_id
self.direction = pid.direction
self.raise_relay_id = pid.raise_relay_id
self.raise_min_duration = pid.raise_min_duration
self.raise_max_duration = pid.raise_max_duration
self.lower_relay_id = pid.lower_relay_id
self.lower_min_duration = pid.lower_min_duration
self.lower_max_duration = pid.lower_max_duration
self.Kp = pid.p
self.Ki = pid.i
self.Kd = pid.d
self.Integrator_min = pid.integrator_min
self.Integrator_max = pid.integrator_max
self.measure_interval = pid.period
self.default_set_point = pid.setpoint
self.set_point = pid.setpoint
self.sensor_duration = sensor.period
return "success"
def update(self, current_value):
"""
Calculate PID output value from reference input and feedback
:return: Manipulated, or control, variable. This is the PID output.
:rtype: float
:param current_value: The input, or process, variable (the actual
measured condition by the sensor)
:type current_value: float
"""
self.error = self.set_point - current_value
# Calculate P-value
self.P_value = self.Kp * self.error
# Calculate I-value
self.Integrator += self.error
# First method for managing Integrator
if self.Integrator > self.Integrator_max:
self.Integrator = self.Integrator_max
elif self.Integrator < self.Integrator_min:
self.Integrator = self.Integrator_min
# Second method for regulating Integrator
# if self.measure_interval is not None:
# if self.Integrator * self.Ki > self.measure_interval:
# self.Integrator = self.measure_interval / self.Ki
# elif self.Integrator * self.Ki < -self.measure_interval:
# self.Integrator = -self.measure_interval / self.Ki
self.I_value = self.Integrator * self.Ki
# Calculate D-value
self.D_value = self.Kd * (self.error - self.Derivator)
self.Derivator = self.error
# Produce output form P, I, and D values
pid_value = self.P_value + self.I_value + self.D_value
return pid_value
def get_last_measurement(self):
"""
Retrieve the latest sensor measurement from InfluxDB
:rtype: None
"""
self.last_measurement_success = False
# Get latest measurement (from within the past minute) from influxdb
try:
if self.sensor_duration < 60:
duration = 60
else:
duration = int(self.sensor_duration * 1.5)
self.last_measurement = read_last_influxdb(self.sensor_id,
self.measure_type,
duration)
if self.last_measurement:
measurement_list = list(
self.last_measurement.get_points(
measurement=self.measure_type))
self.last_time = measurement_list[0]['time']
self.last_measurement = measurement_list[0]['value']
utc_dt = datetime.datetime.strptime(
self.last_time.split(".")[0], '%Y-%m-%dT%H:%M:%S')
utc_timestamp = calendar.timegm(utc_dt.timetuple())
local_timestamp = str(
datetime.datetime.fromtimestamp(utc_timestamp))
self.logger.debug("Latest {}: {} @ {}".format(
self.measure_type, self.last_measurement, local_timestamp))
self.last_measurement_success = True
else:
self.logger.warning("No data returned from influxdb")
except Exception as except_msg:
self.logger.exception(
"Failed to read measurement from the influxdb database: "
"{err}".format(err=except_msg))
def manipulate_relays(self):
"""
Activate a relay based on PID output (control variable) and whether
the manipulation directive is to raise, lower, or both.
:rtype: None
"""
# If there was a measurement able to be retrieved from
# influxdb database that was entered within the past minute
if self.last_measurement_success:
#
# PID control variable positive to raise environmental condition
#
if self.direction in ['raise', 'both'] and self.raise_relay_id:
if self.control_variable > 0:
# Ensure the relay on duration doesn't exceed the set maximum
if (self.raise_max_duration and
self.control_variable > self.raise_max_duration):
self.raise_seconds_on = self.raise_max_duration
else:
self.raise_seconds_on = float("{0:.2f}".format(
self.control_variable))
# Turn off lower_relay if active, because we're now raising
if self.lower_relay_id:
relay = db_retrieve_table(
MYCODO_DB_PATH,
Relay,
device_id=self.lower_relay_id)
if relay.is_on():
self.control.relay_off(self.lower_relay_id)
if self.raise_seconds_on > self.raise_min_duration:
# Activate raise_relay for a duration
self.logger.debug(
"Setpoint: {sp} Output: {op} to relay "
"{relay}".format(sp=self.set_point,
op=self.control_variable,
relay=self.raise_relay_id))
self.control.relay_on(self.raise_relay_id,
self.raise_seconds_on)
else:
self.control.relay_off(self.raise_relay_id)
#
# PID control variable negative to lower environmental condition
#
if self.direction in ['lower', 'both'] and self.lower_relay_id:
if self.control_variable < 0:
# Ensure the relay on duration doesn't exceed the set maximum
if (self.lower_max_duration and abs(self.control_variable)
> self.lower_max_duration):
self.lower_seconds_on = self.lower_max_duration
else:
self.lower_seconds_on = abs(
float("{0:.2f}".format(self.control_variable)))
# Turn off raise_relay if active, because we're now lowering
if self.raise_relay_id:
relay = db_retrieve_table(
MYCODO_DB_PATH,
Relay,
device_id=self.raise_relay_id)
if relay.is_on():
self.control.relay_off(self.raise_relay_id)
if self.lower_seconds_on > self.lower_min_duration:
# Activate lower_relay for a duration
self.logger.debug("Setpoint: {sp} Output: {op} to "
"relay {relay}".format(
sp=self.set_point,
op=self.control_variable,
relay=self.lower_relay_id))
self.control.relay_on(self.lower_relay_id,
self.lower_seconds_on)
else:
self.control.relay_off(self.lower_relay_id)
else:
if self.direction in ['raise', 'both'] and self.raise_relay_id:
self.control.relay_off(self.raise_relay_id)
if self.direction in ['lower', 'both'] and self.lower_relay_id:
self.control.relay_off(self.lower_relay_id)
def calculate_method_setpoint(self, method_id):
method = db_retrieve_table(MYCODO_DB_PATH, Method)
method_key = method.filter(Method.method_id == method_id)
method_key = method_key.filter(Method.method_order == 0).first()
method = method.filter(Method.method_id == method_id)
method = method.filter(Method.relay_id == None)
method = method.filter(Method.method_order > 0)
method = method.order_by(Method.method_order.asc()).all()
now = datetime.datetime.now()
# Calculate where the current time/date is within the time/date method
if method_key.method_type == 'Date':
for each_method in method:
start_time = datetime.datetime.strptime(
each_method.start_time, '%Y-%m-%d %H:%M:%S')
end_time = datetime.datetime.strptime(each_method.end_time,
'%Y-%m-%d %H:%M:%S')
if start_time < now < end_time:
start_setpoint = each_method.start_setpoint
if each_method.end_setpoint:
end_setpoint = each_method.end_setpoint
else:
end_setpoint = each_method.start_setpoint
setpoint_diff = abs(end_setpoint - start_setpoint)
total_seconds = (end_time - start_time).total_seconds()
part_seconds = (now - start_time).total_seconds()
percent_total = part_seconds / total_seconds
if start_setpoint < end_setpoint:
new_setpoint = start_setpoint + (setpoint_diff *
percent_total)
else:
new_setpoint = start_setpoint - (setpoint_diff *
percent_total)
self.logger.debug("[Method] Start: {} End: {}".format(
start_time, end_time))
self.logger.debug("[Method] Start: {} End: {}".format(
start_setpoint, end_setpoint))
self.logger.debug(
"[Method] Total: {} Part total: {} ({}%)".format(
total_seconds, part_seconds, percent_total))
self.logger.debug(
"[Method] New Setpoint: {}".format(new_setpoint))
self.set_point = new_setpoint
return 0
# Calculate where the current Hour:Minute:Seconds is within the Daily method
elif method_key.method_type == 'Daily':
daily_now = datetime.datetime.now().strftime('%H:%M:%S')
daily_now = datetime.datetime.strptime(str(daily_now), '%H:%M:%S')
for each_method in method:
start_time = datetime.datetime.strptime(
each_method.start_time, '%H:%M:%S')
end_time = datetime.datetime.strptime(each_method.end_time,
'%H:%M:%S')
if start_time < daily_now < end_time:
start_setpoint = each_method.start_setpoint
if each_method.end_setpoint:
end_setpoint = each_method.end_setpoint
else:
end_setpoint = each_method.start_setpoint
setpoint_diff = abs(end_setpoint - start_setpoint)
total_seconds = (end_time - start_time).total_seconds()
part_seconds = (daily_now - start_time).total_seconds()
percent_total = part_seconds / total_seconds
if start_setpoint < end_setpoint:
new_setpoint = start_setpoint + (setpoint_diff *
percent_total)
else:
new_setpoint = start_setpoint - (setpoint_diff *
percent_total)
self.logger.debug("[Method] Start: {} End: {}".format(
start_time.strftime('%H:%M:%S'),
end_time.strftime('%H:%M:%S')))
self.logger.debug("[Method] Start: {} End: {}".format(
start_setpoint, end_setpoint))
self.logger.debug(
"[Method] Total: {} Part total: {} ({}%)".format(
total_seconds, part_seconds, percent_total))
self.logger.debug(
"[Method] New Setpoint: {}".format(new_setpoint))
self.set_point = new_setpoint
return 0
# Calculate sine y-axis value from the x-axis (seconds of the day)
elif method_key.method_type == 'DailySine':
new_setpoint = sine_wave_y_out(method_key.amplitude,
method_key.frequency,
method_key.shift_angle,
method_key.shift_y)
self.set_point = new_setpoint
return 0
# Calculate Bezier curve y-axis value from the x-axis (seconds of the day)
elif method_key.method_type == 'DailyBezier':
new_setpoint = bezier_curve_y_out(method_key.shift_angle,
(method_key.x0, method_key.y0),
(method_key.x1, method_key.y1),
(method_key.x2, method_key.y2),
(method_key.x3, method_key.y3))
self.set_point = new_setpoint
return 0
# Calculate the duration in the method based on self.method_start_time
elif method_key.method_type == 'Duration' and self.method_start_time != 'Ended':
seconds_from_start = (now - self.method_start_time).total_seconds()
total_sec = 0
previous_total_sec = 0
for each_method in method:
total_sec += each_method.duration_sec
if previous_total_sec <= seconds_from_start < total_sec:
row_start_time = float(
self.method_start_time.strftime(
'%s')) + previous_total_sec
row_since_start_sec = (
now - (self.method_start_time + datetime.timedelta(
0, previous_total_sec))).total_seconds()
percent_row = row_since_start_sec / each_method.duration_sec
start_setpoint = each_method.start_setpoint
if each_method.end_setpoint:
end_setpoint = each_method.end_setpoint
else:
end_setpoint = each_method.start_setpoint
setpoint_diff = abs(end_setpoint - start_setpoint)
if start_setpoint < end_setpoint:
new_setpoint = start_setpoint + (setpoint_diff *
percent_row)
else:
new_setpoint = start_setpoint - (setpoint_diff *
percent_row)
self.logger.debug(
"[Method] Start: {} Seconds Since: {}".format(
self.method_start_time, seconds_from_start))
self.logger.debug("[Method] Start time of row: {}".format(
datetime.datetime.fromtimestamp(row_start_time)))
self.logger.debug(
"[Method] Sec since start of row: {}".format(
row_since_start_sec))
self.logger.debug(
"[Method] Percent of row: {}".format(percent_row))
self.logger.debug(
"[Method] New Setpoint: {}".format(new_setpoint))
self.set_point = new_setpoint
return 0
previous_total_sec = total_sec
# Duration method has ended, reset start_time locally and in DB
if self.method_start_time:
with session_scope(MYCODO_DB_PATH) as db_session:
mod_method = db_session.query(Method).filter(
Method.method_id == self.method_id)
mod_method = mod_method.filter(
Method.method_order == 0).first()
mod_method.start_time = 'Ended'
db_session.commit()
self.method_start_time = 'Ended'
# Setpoint not needing to be calculated, use default setpoint
self.set_point = self.default_set_point
def pid_mod(self):
if self.initialize_values():
return "success"
else:
return "error"
def pid_hold(self):
self.activated = 3
self.logger.info("Hold")
return "success"
def pid_pause(self):
self.activated = 2
self.logger.info("Pause")
return "success"
def pid_resume(self):
self.activated = 1
self.logger.info("Resume")
return "success"
def set_setpoint(self, set_point):
""" Initilize the setpoint of PID """
self.set_point = set_point
self.Integrator = 0
self.Derivator = 0
def set_integrator(self, Integrator):
""" Set the Integrator of the controller """
self.Integrator = Integrator
def set_derivator(self, Derivator):
""" Set the Derivator of the controller """
self.Derivator = Derivator
def set_kp(self, P):
""" Set Kp gain of the controller """
self.Kp = P
def set_ki(self, I):
""" Set Ki gain of the controller """
self.Ki = I
def set_kd(self, D):
""" Set Kd gain of the controller """
self.Kd = D
def get_setpoint(self):
return self.set_point
def get_error(self):
return self.error
def get_integrator(self):
return self.Integrator
def get_derivator(self):
return self.Derivator
def is_running(self):
return self.running
def stop_controller(self):
self.thread_shutdown_timer = timeit.default_timer()
self.running = False
# Unset method start time
if self.method_id:
with session_scope(MYCODO_DB_PATH) as db_session:
mod_method = db_session.query(Method)
mod_method = mod_method.filter(
Method.method_id == self.method_id)
mod_method = mod_method.filter(
Method.method_order == 0).first()
mod_method.start_time = 'Ended'
db_session.commit()
class TimerController(threading.Thread):
"""
class for controlling timers
"""
def __init__(self, ready, timer_id):
threading.Thread.__init__(self)
self.logger = logging.getLogger(
"mycodo.timer_{id}".format(id=timer_id))
self.thread_startup_timer = timeit.default_timer()
self.thread_shutdown_timer = 0
self.ready = ready
self.timer_id = timer_id
self.control = DaemonControl()
timer = db_retrieve_table_daemon(Timer, device_id=self.timer_id)
self.timer_type = timer.timer_type
self.output_unique_id = timer.relay_id
self.method_id = timer.method_id
self.method_period = timer.method_period
self.state = timer.state
self.time_start = timer.time_start
self.time_end = timer.time_end
self.duration_on = timer.duration_on
self.duration_off = timer.duration_off
self.output_id = db_retrieve_table_daemon(
Output, unique_id=self.output_unique_id).id
# Time of day split into hour and minute
if self.time_start:
time_split = self.time_start.split(":")
self.start_hour = time_split[0]
self.start_minute = time_split[1]
else:
self.start_hour = None
self.start_minute = None
if self.time_end:
time_split = self.time_end.split(":")
self.end_hour = time_split[0]
self.end_minute = time_split[1]
else:
self.end_hour = None
self.end_minute = None
self.duration_timer = time.time()
self.pwm_method_timer = time.time()
self.date_timer_not_executed = True
self.running = False
if self.method_id:
method = db_retrieve_table_daemon(Method, device_id=self.method_id)
method_data = db_retrieve_table_daemon(MethodData)
method_data = method_data.filter(
MethodData.method_id == self.method_id)
method_data_repeat = method_data.filter(
MethodData.duration_sec == 0).first()
self.method_type = method.method_type
self.method_start_act = timer.method_start_time
self.method_start_time = None
self.method_end_time = None
if self.method_type == 'Duration':
if self.method_start_act == 'Ended':
self.stop_controller(ended_normally=False,
deactivate_timer=True)
self.logger.warning(
"Method has ended. "
"Activate the Timer controller to start it again.")
elif self.method_start_act == 'Ready' or self.method_start_act is None:
# Method has been instructed to begin
now = datetime.datetime.now()
self.method_start_time = now
if method_data_repeat and method_data_repeat.duration_end:
self.method_end_time = now + datetime.timedelta(
seconds=float(method_data_repeat.duration_end))
with session_scope(MYCODO_DB_PATH) as db_session:
mod_timer = db_session.query(Timer)
mod_timer = mod_timer.filter(
Timer.id == self.timer_id).first()
mod_timer.method_start_time = self.method_start_time
mod_timer.method_end_time = self.method_end_time
db_session.commit()
else:
# Method neither instructed to begin or not to
# Likely there was a daemon restart ot power failure
# Resume method with saved start_time
self.method_start_time = datetime.datetime.strptime(
str(timer.method_start_time), '%Y-%m-%d %H:%M:%S.%f')
if method_data_repeat and method_data_repeat.duration_end:
self.method_end_time = datetime.datetime.strptime(
str(timer.method_end_time), '%Y-%m-%d %H:%M:%S.%f')
if self.method_end_time > datetime.datetime.now():
self.logger.warning(
"Resuming method {id}: started {start}, "
"ends {end}".format(id=self.method_id,
start=self.method_start_time,
end=self.method_end_time))
else:
self.method_start_act = 'Ended'
else:
self.method_start_act = 'Ended'
def run(self):
self.running = True
self.logger.info("Activated in {:.1f} ms".format(
(timeit.default_timer() - self.thread_startup_timer) * 1000))
self.ready.set()
while self.running:
# Timer is set to react at a specific hour and minute of the day
if self.timer_type == 'time':
if (int(self.start_hour) == datetime.datetime.now().hour
and int(self.start_minute)
== datetime.datetime.now().minute):
# Ensure this is triggered only once at this specific time
if self.date_timer_not_executed:
self.date_timer_not_executed = False
message = "At {st}, turn Output {id} {state}".format(
st=self.time_start,
id=self.output_id,
state=self.state)
if self.state == 'on' and self.duration_on:
message += " for {sec} seconds".format(
sec=self.duration_on)
else:
self.duration_on = 0
self.logger.debug(message)
modulate_output = threading.Thread(
target=self.control.output_on_off,
args=(
self.output_id,
self.state,
),
kwargs={'duration': self.duration_on})
modulate_output.start()
elif not self.date_timer_not_executed:
self.date_timer_not_executed = True
# Timer is set to react at a specific time duration of the day
elif self.timer_type == 'timespan':
if time_between_range(self.time_start, self.time_end):
current_output_state = self.control.relay_state(
self.output_id)
if self.state != current_output_state:
message = "Output {output} should be {state}, but is " \
"{cstate}. Turning {state}.".format(
output=self.output_id,
state=self.state,
cstate=current_output_state)
modulate_output = threading.Thread(
target=self.control.output_on_off,
args=(
self.output_id,
self.state,
))
modulate_output.start()
self.logger.debug(message)
# Timer is a simple on/off duration timer
elif self.timer_type == 'duration':
if time.time() > self.duration_timer:
self.duration_timer = (time.time() + self.duration_on +
self.duration_off)
self.logger.debug("Turn Output {output} on for {onsec} "
"seconds, then off for {offsec} "
"seconds".format(
output=self.output_id,
onsec=self.duration_on,
offsec=self.duration_off))
output_on = threading.Thread(target=self.control.relay_on,
args=(
self.output_id,
self.duration_on,
))
output_on.start()
# Timer is a PWM Method timer
elif self.timer_type == 'pwm_method':
try:
if time.time() > self.pwm_method_timer:
if self.method_start_act == 'Ended':
self.stop_controller(ended_normally=False,
deactivate_timer=True)
self.logger.info(
"Method has ended. "
"Activate the Timer controller to start it again."
)
else:
this_controller = db_retrieve_table_daemon(
Timer, device_id=self.timer_id)
setpoint, ended = calculate_method_setpoint(
self.method_id, Timer, this_controller, Method,
MethodData, self.logger)
if ended:
self.method_start_act = 'Ended'
if setpoint > 100:
setpoint = 100
elif setpoint < 0:
setpoint = 0
self.logger.debug(
"Turn Output {output} to a PWM duty cycle of "
"{dc:.1f} %".format(output=self.output_id,
dc=setpoint))
# Activate pwm with calculated duty cycle
self.control.relay_on(self.output_id,
duty_cycle=setpoint)
self.pwm_method_timer = time.time(
) + self.method_period
except Exception:
self.logger.exception(1)
time.sleep(0.1)
self.control.relay_off(self.output_id)
self.running = False
self.logger.info("Deactivated in {:.1f} ms".format(
(timeit.default_timer() - self.thread_shutdown_timer) * 1000))
def is_running(self):
return self.running
def stop_controller(self, ended_normally=True, deactivate_timer=False):
self.thread_shutdown_timer = timeit.default_timer()
self.running = False
# Unset method start time
if self.method_id and ended_normally:
with session_scope(MYCODO_DB_PATH) as db_session:
mod_timer = db_session.query(Timer).filter(
Timer.id == self.timer_id).first()
mod_timer.method_start_time = 'Ended'
mod_timer.method_end_time = None
db_session.commit()
if deactivate_timer:
with session_scope(MYCODO_DB_PATH) as db_session:
mod_timer = db_session.query(Timer).filter(
Timer.id == self.timer_id).first()
mod_timer.is_activated = False
db_session.commit()
class PIDController(threading.Thread):
"""
Class to operate discrete PID controller
"""
def __init__(self, ready, pid_id):
threading.Thread.__init__(self)
self.logger = logging.getLogger("mycodo.pid_{id}".format(id=pid_id))
self.running = False
self.thread_startup_timer = timeit.default_timer()
self.thread_shutdown_timer = 0
self.ready = ready
self.pid_id = pid_id
self.pid_unique_id = db_retrieve_table_daemon(
PID, device_id=self.pid_id).unique_id
self.control = DaemonControl()
self.control_variable = 0.0
self.derivator = 0.0
self.integrator = 0.0
self.error = 0.0
self.P_value = None
self.I_value = None
self.D_value = None
self.set_point = 0.0
self.lower_seconds_on = 0.0
self.raise_seconds_on = 0.0
self.lower_duty_cycle = 0.0
self.raise_duty_cycle = 0.0
self.last_time = None
self.last_measurement = None
self.last_measurement_success = False
self.is_activated = None
self.is_held = None
self.is_paused = None
self.pid_type = None
self.measurement = None
self.method_id = None
self.direction = None
self.raise_relay_id = None
self.raise_min_duration = None
self.raise_max_duration = None
self.raise_min_off_duration = None
self.lower_relay_id = None
self.lower_min_duration = None
self.lower_max_duration = None
self.lower_min_off_duration = None
self.Kp = None
self.Ki = None
self.Kd = None
self.integrator_min = None
self.integrator_max = None
self.period = None
self.max_measure_age = None
self.default_set_point = None
self.set_point = None
self.sensor_unique_id = None
self.sensor_duration = None
self.initialize_values()
self.timer = t.time() + self.period
# Check if a method is set for this PID
if self.method_id:
method = db_retrieve_table_daemon(Method, device_id=self.method_id)
self.method_type = method.method_type
self.method_start_time = method.start_time
if self.method_type == 'Duration':
if self.method_start_time == 'Ended':
# Method has ended and hasn't been instructed to begin again
pass
elif self.method_start_time == 'Ready' or self.method_start_time is None:
# Method has been instructed to begin
with session_scope(MYCODO_DB_PATH) as db_session:
mod_method = db_session.query(Method)
mod_method = mod_method.filter(
Method.id == self.method_id).first()
mod_method.time_start = datetime.datetime.now()
self.method_start_time = mod_method.start_time
db_session.commit()
else:
# Method neither instructed to begin or not to
# Likely there was a daemon restart ot power failure
# Resume method with saved start_time
self.method_start_time = datetime.datetime.strptime(
str(self.method_start_time), '%Y-%m-%d %H:%M:%S.%f')
self.logger.warning(
"Resuming method {id} started at {time}".format(
id=self.method_id, time=self.method_start_time))
def run(self):
try:
self.running = True
self.logger.info("Activated in {:.1f} ms".format(
(timeit.default_timer() - self.thread_startup_timer) * 1000))
if self.is_paused:
self.logger.info("Paused")
elif self.is_held:
self.logger.info("Held")
self.ready.set()
while self.running:
if t.time() > self.timer:
# Ensure the timer ends in the future
while t.time() > self.timer:
self.timer = self.timer + self.period
# If PID is active, retrieve sensor measurement and update PID output
if self.is_activated and not self.is_paused:
self.get_last_measurement()
if self.last_measurement_success:
# Update setpoint using a method if one is selected
if self.method_id:
self.calculate_method_setpoint(self.method_id)
write_setpoint_db = threading.Thread(
target=write_influxdb_value,
args=(
self.pid_unique_id,
'setpoint',
self.set_point,
))
write_setpoint_db.start()
# Update PID and get control variable
self.control_variable = self.update_pid_output(
self.last_measurement)
if self.pid_type == 'relay':
pid_entry_type = 'pid_output'
pid_entry_value = self.control_variable
elif self.pid_type == 'pwm':
pid_entry_type = 'duty_cycle'
pid_entry_value = self.control_var_to_duty_cycle(
abs(self.control_variable))
if self.control_variable < 0:
pid_entry_value = -pid_entry_value
else:
pid_entry_type = None
pid_entry_value = None
if pid_entry_type:
write_pid_out_db = threading.Thread(
target=write_influxdb_value,
args=(
self.pid_unique_id,
pid_entry_type,
pid_entry_value,
))
write_pid_out_db.start()
# If PID is active or on hold, activate relays
if ((self.is_activated and not self.is_paused)
or (self.is_activated and self.is_held)):
self.manipulate_output()
t.sleep(0.1)
# Turn off relay used in PID when the controller is deactivated
if self.raise_relay_id and self.direction in ['raise', 'both']:
self.control.relay_off(self.raise_relay_id,
trigger_conditionals=True)
if self.lower_relay_id and self.direction in ['lower', 'both']:
self.control.relay_off(self.lower_relay_id,
trigger_conditionals=True)
self.running = False
self.logger.info("Deactivated in {:.1f} ms".format(
(timeit.default_timer() - self.thread_shutdown_timer) * 1000))
except Exception as except_msg:
self.logger.exception("Run Error: {err}".format(err=except_msg))
def initialize_values(self):
"""Set PID parameters"""
pid = db_retrieve_table_daemon(PID, device_id=self.pid_id)
self.is_activated = pid.is_activated
self.is_held = pid.is_held
self.is_paused = pid.is_paused
self.pid_type = pid.pid_type
self.measurement = pid.measurement
self.method_id = pid.method_id
self.direction = pid.direction
self.raise_relay_id = pid.raise_relay_id
self.raise_min_duration = pid.raise_min_duration
self.raise_max_duration = pid.raise_max_duration
self.raise_min_off_duration = pid.raise_min_off_duration
self.lower_relay_id = pid.lower_relay_id
self.lower_min_duration = pid.lower_min_duration
self.lower_max_duration = pid.lower_max_duration
self.lower_min_off_duration = pid.lower_min_off_duration
self.Kp = pid.p
self.Ki = pid.i
self.Kd = pid.d
self.integrator_min = pid.integrator_min
self.integrator_max = pid.integrator_max
self.period = pid.period
self.max_measure_age = pid.max_measure_age
self.default_set_point = pid.setpoint
self.set_point = pid.setpoint
sensor = db_retrieve_table_daemon(Sensor, device_id=pid.sensor_id)
self.sensor_unique_id = sensor.unique_id
self.sensor_duration = sensor.period
return "success"
def update_pid_output(self, current_value):
"""
Calculate PID output value from reference input and feedback
:return: Manipulated, or control, variable. This is the PID output.
:rtype: float
:param current_value: The input, or process, variable (the actual
measured condition by the sensor)
:type current_value: float
"""
self.error = self.set_point - current_value
# Calculate P-value
self.P_value = self.Kp * self.error
# Calculate I-value
self.integrator += self.error
# First method for managing integrator
if self.integrator > self.integrator_max:
self.integrator = self.integrator_max
elif self.integrator < self.integrator_min:
self.integrator = self.integrator_min
# Second method for regulating integrator
# if self.period is not None:
# if self.integrator * self.Ki > self.period:
# self.integrator = self.period / self.Ki
# elif self.integrator * self.Ki < -self.period:
# self.integrator = -self.period / self.Ki
self.I_value = self.integrator * self.Ki
# Calculate D-value
self.D_value = self.Kd * (self.error - self.derivator)
self.derivator = self.error
# Produce output form P, I, and D values
pid_value = self.P_value + self.I_value + self.D_value
return pid_value
def get_last_measurement(self):
"""
Retrieve the latest sensor measurement from InfluxDB
:rtype: None
"""
self.last_measurement_success = False
# Get latest measurement (from within the past minute) from influxdb
try:
if self.sensor_duration < 60:
duration = 60
else:
duration = int(self.sensor_duration * 1.5)
self.last_measurement = read_last_influxdb(self.sensor_unique_id,
self.measurement,
duration)
if self.last_measurement:
self.last_time = self.last_measurement[0]
self.last_measurement = self.last_measurement[1]
utc_dt = datetime.datetime.strptime(
self.last_time.split(".")[0], '%Y-%m-%dT%H:%M:%S')
utc_timestamp = calendar.timegm(utc_dt.timetuple())
local_timestamp = str(
datetime.datetime.fromtimestamp(utc_timestamp))
self.logger.debug("Latest {meas}: {last} @ {ts}".format(
meas=self.measurement,
last=self.last_measurement,
ts=local_timestamp))
if calendar.timegm(
t.gmtime()) - utc_timestamp > self.max_measure_age:
self.logger.error(
"Last measurement was {last_sec} seconds ago, however"
" the maximum measurement age is set to {max_sec}"
" seconds.".format(
last_sec=calendar.timegm(t.gmtime()) -
utc_timestamp,
max_sec=self.max_measure_age))
self.last_measurement_success = True
else:
self.logger.warning("No data returned from influxdb")
except requests.ConnectionError:
self.logger.error("Failed to read measurement from the "
"influxdb database: Could not connect.")
except Exception as except_msg:
self.logger.exception(
"Exception while reading measurement from the influxdb "
"database: {err}".format(err=except_msg))
def manipulate_output(self):
"""
Activate output based on PID control variable and whether
the manipulation directive is to raise, lower, or both.
:rtype: None
"""
# If the last measurement was able to be retrieved and was entered within the past minute
if self.last_measurement_success:
#
# PID control variable is positive, indicating a desire to raise
# the environmental condition
#
if self.direction in ['raise', 'both'] and self.raise_relay_id:
if self.control_variable > 0:
# Turn off lower_relay if active, because we're now raising
if (self.direction == 'both' and self.lower_relay_id
and self.control.relay_state(
self.lower_relay_id) != 'off'):
self.control.relay_off(self.lower_relay_id)
if self.pid_type == 'relay':
# Ensure the relay on duration doesn't exceed the set maximum
if (self.raise_max_duration and self.control_variable >
self.raise_max_duration):
self.raise_seconds_on = self.raise_max_duration
else:
self.raise_seconds_on = float("{0:.2f}".format(
self.control_variable))
if self.raise_seconds_on > self.raise_min_duration:
# Activate raise_relay for a duration
self.logger.debug(
"Setpoint: {sp} Output: {cv} to relay "
"{id}".format(sp=self.set_point,
cv=self.control_variable,
id=self.raise_relay_id))
self.control.relay_on(
self.raise_relay_id,
duration=self.raise_seconds_on,
min_off=self.raise_min_off_duration)
elif self.pid_type == 'pwm':
self.raise_duty_cycle = float("{0:.1f}".format(
self.control_var_to_duty_cycle(
self.control_variable)))
# Ensure the duty cycle doesn't exceed the min/max
if (self.raise_max_duration and self.raise_duty_cycle >
self.raise_max_duration):
self.raise_duty_cycle = self.raise_max_duration
elif (self.raise_min_duration and
self.raise_duty_cycle < self.raise_min_duration):
self.raise_duty_cycle = self.raise_min_duration
self.logger.debug(
"Setpoint: {sp}, Control Variable: {cv}, Output: PWM output "
"{id} to {dc:.1f}%".format(
sp=self.set_point,
cv=self.control_variable,
id=self.raise_relay_id,
dc=self.raise_duty_cycle))
# Activate pwm with calculated duty cycle
self.control.relay_on(self.raise_relay_id,
duty_cycle=self.raise_duty_cycle)
else:
if self.pid_type == 'relay':
self.control.relay_off(self.raise_relay_id)
elif self.pid_type == 'pwm':
self.control.relay_on(self.raise_relay_id,
duty_cycle=0)
#
# PID control variable is negative, indicating a desire to lower
# the environmental condition
#
if self.direction in ['lower', 'both'] and self.lower_relay_id:
if self.control_variable < 0:
# Turn off raise_relay if active, because we're now raising
if (self.direction == 'both' and self.raise_relay_id
and self.control.relay_state(
self.raise_relay_id) != 'off'):
self.control.relay_off(self.raise_relay_id)
if self.pid_type == 'relay':
# Ensure the relay on duration doesn't exceed the set maximum
if (self.lower_max_duration
and abs(self.control_variable) >
self.lower_max_duration):
self.lower_seconds_on = self.lower_max_duration
else:
self.lower_seconds_on = abs(
float("{0:.2f}".format(self.control_variable)))
if self.lower_seconds_on > self.lower_min_duration:
# Activate lower_relay for a duration
self.logger.debug("Setpoint: {sp} Output: {cv} to "
"relay {id}".format(
sp=self.set_point,
cv=self.control_variable,
id=self.lower_relay_id))
self.control.relay_on(
self.lower_relay_id,
duration=self.lower_seconds_on,
min_off=self.lower_min_off_duration)
elif self.pid_type == 'pwm':
self.lower_duty_cycle = float("{0:.1f}".format(
self.control_var_to_duty_cycle(
abs(self.control_variable))))
# Ensure the duty cycle doesn't exceed the min/max
if (self.lower_max_duration and self.lower_duty_cycle >
self.lower_max_duration):
self.lower_duty_cycle = -self.lower_max_duration
elif (self.lower_min_duration and
self.lower_duty_cycle < self.lower_min_duration):
self.lower_duty_cycle = -self.lower_min_duration
self.logger.debug(
"Setpoint: {sp}, Control Variable: {cv}, Output: PWM output "
"{id} to {dc:.1f}%".format(
sp=self.set_point,
cv=self.control_variable,
id=self.lower_relay_id,
dc=self.lower_duty_cycle))
# Turn back negative for proper logging
if self.control_variable < 0:
self.lower_duty_cycle = -self.lower_duty_cycle
# Activate pwm with calculated duty cycle
self.control.relay_on(self.lower_relay_id,
duty_cycle=self.lower_duty_cycle)
else:
if self.pid_type == 'relay':
self.control.relay_off(self.lower_relay_id)
elif self.pid_type == 'pwm':
self.control.relay_on(self.lower_relay_id,
duty_cycle=0)
else:
if self.direction in ['raise', 'both'] and self.raise_relay_id:
self.control.relay_off(self.raise_relay_id)
if self.direction in ['lower', 'both'] and self.lower_relay_id:
self.control.relay_off(self.lower_relay_id)
def calculate_method_setpoint(self, method_id):
method = db_retrieve_table_daemon(Method)
method_key = method.filter(Method.id == method_id).first()
method_data = db_retrieve_table_daemon(MethodData)
method_data = method_data.filter(MethodData.method_id == method_id)
method_data_all = method_data.filter(MethodData.relay_id == None).all()
method_data_first = method_data.filter(
MethodData.relay_id == None).first()
now = datetime.datetime.now()
# Calculate where the current time/date is within the time/date method
if method_key.method_type == 'Date':
for each_method in method_data_all:
start_time = datetime.datetime.strptime(
each_method.time_start, '%Y-%m-%d %H:%M:%S')
end_time = datetime.datetime.strptime(each_method.time_end,
'%Y-%m-%d %H:%M:%S')
if start_time < now < end_time:
setpoint_start = each_method.setpoint_start
if each_method.setpoint_end:
setpoint_end = each_method.setpoint_end
else:
setpoint_end = each_method.setpoint_start
setpoint_diff = abs(setpoint_end - setpoint_start)
total_seconds = (end_time - start_time).total_seconds()
part_seconds = (now - start_time).total_seconds()
percent_total = part_seconds / total_seconds
if setpoint_start < setpoint_end:
new_setpoint = setpoint_start + (setpoint_diff *
percent_total)
else:
new_setpoint = setpoint_start - (setpoint_diff *
percent_total)
self.logger.debug("[Method] Start: {} End: {}".format(
start_time, end_time))
self.logger.debug("[Method] Start: {} End: {}".format(
setpoint_start, setpoint_end))
self.logger.debug(
"[Method] Total: {} Part total: {} ({}%)".format(
total_seconds, part_seconds, percent_total))
self.logger.debug(
"[Method] New Setpoint: {}".format(new_setpoint))
self.set_point = new_setpoint
return 0
# Calculate where the current Hour:Minute:Seconds is within the Daily method
elif method_key.method_type == 'Daily':
daily_now = datetime.datetime.now().strftime('%H:%M:%S')
daily_now = datetime.datetime.strptime(str(daily_now), '%H:%M:%S')
for each_method in method_data_all:
start_time = datetime.datetime.strptime(
each_method.time_start, '%H:%M:%S')
end_time = datetime.datetime.strptime(each_method.time_end,
'%H:%M:%S')
if start_time < daily_now < end_time:
setpoint_start = each_method.setpoint_start
if each_method.setpoint_end:
setpoint_end = each_method.setpoint_end
else:
setpoint_end = each_method.setpoint_start
setpoint_diff = abs(setpoint_end - setpoint_start)
total_seconds = (end_time - start_time).total_seconds()
part_seconds = (daily_now - start_time).total_seconds()
percent_total = part_seconds / total_seconds
if setpoint_start < setpoint_end:
new_setpoint = setpoint_start + (setpoint_diff *
percent_total)
else:
new_setpoint = setpoint_start - (setpoint_diff *
percent_total)
self.logger.debug("[Method] Start: {} End: {}".format(
start_time.strftime('%H:%M:%S'),
end_time.strftime('%H:%M:%S')))
self.logger.debug("[Method] Start: {} End: {}".format(
setpoint_start, setpoint_end))
self.logger.debug(
"[Method] Total: {} Part total: {} ({}%)".format(
total_seconds, part_seconds, percent_total))
self.logger.debug(
"[Method] New Setpoint: {}".format(new_setpoint))
self.set_point = new_setpoint
return 0
# Calculate sine y-axis value from the x-axis (seconds of the day)
elif method_key.method_type == 'DailySine':
new_setpoint = sine_wave_y_out(method_data_first.amplitude,
method_data_first.frequency,
method_data_first.shift_angle,
method_data_first.shift_y)
self.set_point = new_setpoint
return 0
# Calculate Bezier curve y-axis value from the x-axis (seconds of the day)
elif method_key.method_type == 'DailyBezier':
new_setpoint = bezier_curve_y_out(
method_data_first.shift_angle,
(method_data_first.x0, method_data_first.y0),
(method_data_first.x1, method_data_first.y1),
(method_data_first.x2, method_data_first.y2),
(method_data_first.x3, method_data_first.y3))
self.set_point = new_setpoint
return 0
# Calculate the duration in the method based on self.method_start_time
elif method_key.method_type == 'Duration' and self.method_start_time != 'Ended':
seconds_from_start = (now - self.method_start_time).total_seconds()
total_sec = 0
previous_total_sec = 0
for each_method in method_data_all:
total_sec += each_method.duration_sec
if previous_total_sec <= seconds_from_start < total_sec:
row_start_time = float(
self.method_start_time.strftime(
'%s')) + previous_total_sec
row_since_start_sec = (
now - (self.method_start_time + datetime.timedelta(
0, previous_total_sec))).total_seconds()
percent_row = row_since_start_sec / each_method.duration_sec
setpoint_start = each_method.setpoint_start
if each_method.setpoint_end:
setpoint_end = each_method.setpoint_end
else:
setpoint_end = each_method.setpoint_start
setpoint_diff = abs(setpoint_end - setpoint_start)
if setpoint_start < setpoint_end:
new_setpoint = setpoint_start + (setpoint_diff *
percent_row)
else:
new_setpoint = setpoint_start - (setpoint_diff *
percent_row)
self.logger.debug(
"[Method] Start: {} Seconds Since: {}".format(
self.method_start_time, seconds_from_start))
self.logger.debug("[Method] Start time of row: {}".format(
datetime.datetime.fromtimestamp(row_start_time)))
self.logger.debug(
"[Method] Sec since start of row: {}".format(
row_since_start_sec))
self.logger.debug(
"[Method] Percent of row: {}".format(percent_row))
self.logger.debug(
"[Method] New Setpoint: {}".format(new_setpoint))
self.set_point = new_setpoint
return 0
previous_total_sec = total_sec
# Duration method has ended, reset method_start_time locally and in DB
if self.method_start_time:
with session_scope(MYCODO_DB_PATH) as db_session:
mod_method = db_session.query(Method).filter(
Method.id == self.method_id).first()
mod_method.method_start_time = 'Ended'
db_session.commit()
self.method_start_time = 'Ended'
# Setpoint not needing to be calculated, use default setpoint
self.set_point = self.default_set_point
def control_var_to_duty_cycle(self, control_variable):
# Convert control variable to duty cycle
if control_variable > self.period:
return 100.0
else:
return float((control_variable / self.period) * 100)
def pid_mod(self):
if self.initialize_values():
return "success"
else:
return "error"
def pid_hold(self):
self.is_held = True
self.logger.info("Hold")
return "success"
def pid_pause(self):
self.is_paused = True
self.logger.info("Pause")
return "success"
def pid_resume(self):
self.is_activated = True
self.is_held = False
self.is_paused = False
self.logger.info("Resume")
return "success"
def set_setpoint(self, set_point):
""" Initilize the setpoint of PID """
self.set_point = set_point
self.integrator = 0
self.derivator = 0
def set_integrator(self, integrator):
""" Set the integrator of the controller """
self.integrator = integrator
def set_derivator(self, derivator):
""" Set the derivator of the controller """
self.derivator = derivator
def set_kp(self, p):
""" Set Kp gain of the controller """
self.Kp = p
def set_ki(self, i):
""" Set Ki gain of the controller """
self.Ki = i
def set_kd(self, d):
""" Set Kd gain of the controller """
self.Kd = d
def get_setpoint(self):
return self.set_point
def get_error(self):
return self.error
def get_integrator(self):
return self.integrator
def get_derivator(self):
return self.derivator
def is_running(self):
return self.running
def stop_controller(self):
self.thread_shutdown_timer = timeit.default_timer()
self.running = False
# Unset method start time
if self.method_id:
with session_scope(MYCODO_DB_PATH) as db_session:
mod_method = db_session.query(Method).filter(
Method.id == self.method_id).first()
mod_method.method_start_time = 'Ended'
db_session.commit()
class PIDController(threading.Thread):
"""
Class to operate discrete PID controller
"""
def __init__(self, ready, logger, pid_id):
threading.Thread.__init__(self)
self.thread_startup_timer = timeit.default_timer()
self.thread_shutdown_timer = 0
self.ready = ready
self.logger = logger
self.pid_id = pid_id
self.control = DaemonControl()
with session_scope(MYCODO_DB_PATH) as new_session:
pid = new_session.query(PID).filter(PID.id == self.pid_id).first()
self.sensor_id = pid.sensor_id
self.measure_type = pid.measure_type
self.method_id = pid.method_id
self.direction = pid.direction
self.raise_relay_id = pid.raise_relay_id
self.raise_min_duration = pid.raise_min_duration
self.raise_max_duration = pid.raise_max_duration
self.lower_relay_id = pid.lower_relay_id
self.lower_min_duration = pid.lower_min_duration
self.lower_max_duration = pid.lower_max_duration
self.Kp = pid.p
self.Ki = pid.i
self.Kd = pid.d
self.Integrator_min = pid.integrator_min
self.Integrator_max = pid.integrator_max
self.measure_interval = pid.period
self.default_set_point = pid.setpoint
self.set_point = pid.setpoint
sensor = new_session.query(Sensor).filter(Sensor.id == self.sensor_id).first()
self.sensor_duration = sensor.period
self.Derivator = 0
self.Integrator = 0
self.error = 0.0
self.P_value = None
self.I_value = None
self.D_value = None
self.raise_seconds_on = 0
self.timer = t.time()+self.measure_interval
# Check if a method is set for this PID
if self.method_id:
with session_scope(MYCODO_DB_PATH) as new_session:
method = new_session.query(Method)
method = method.filter(Method.method_id == self.method_id)
method = method.filter(Method.method_order == 0).first()
self.method_type = method.method_type
self.method_start_time = method.start_time
if self.method_type == 'Duration':
if self.method_start_time == 'Ended':
# Method has ended and hasn't been instructed to begin again
pass
elif self.method_start_time == 'Ready' or self.method_start_time == None:
# Method has been instructed to begin
with session_scope(MYCODO_DB_PATH) as db_session:
mod_method = db_session.query(Method)
mod_method = mod_method.filter(Method.method_id == self.method_id)
mod_method = mod_method.filter(Method.method_order == 0).first()
mod_method.start_time = datetime.datetime.now()
self.method_start_time = mod_method.start_time
db_session.commit()
else:
# Method neither instructed to begin or not to
# Likely there was a daemon restart ot power failure
# Resume method with saved start_time
self.method_start_time = datetime.datetime.strptime(
self.method_start_time, '%Y-%m-%d %H:%M:%S.%f')
self.logger.warning("[PID {}] Resuming method {} started at {}".format(
self.pid_id, self.method_id, self.method_start_time))
def run(self):
try:
self.running = True
self.logger.info("[PID {}] Activated in {:.1f} ms".format(
self.pid_id,
(timeit.default_timer()-self.thread_startup_timer)*1000))
self.ready.set()
while (self.running):
if t.time() > self.timer:
self.timer = self.timer+self.measure_interval
self.get_last_measurement()
self.manipulate_relays()
t.sleep(0.1)
if self.raise_relay_id:
self.control.relay_off(self.raise_relay_id)
if self.lower_relay_id:
self.control.relay_off(self.lower_relay_id)
self.running = False
self.logger.info("[PID {}] Deactivated in {:.1f} ms".format(
self.pid_id,
(timeit.default_timer()-self.thread_shutdown_timer)*1000))
except Exception as except_msg:
self.logger.exception("[PID {}] Error: {}".format(self.pid_id,
except_msg))
def update(self, current_value):
"""
Calculate PID output value from reference input and feedback
:return: Manipulated, or control, variable. This is the PID output.
:rtype: float
:param current_value: The input, or process, variable (the actual
measured condition by the sensor)
:type current_value: float
"""
self.error = self.set_point - current_value
# Calculate P-value
self.P_value = self.Kp * self.error
# Calculate I-value
self.Integrator += self.error
# First method for managing Integrator
if self.Integrator > self.Integrator_max:
self.Integrator = self.Integrator_max
elif self.Integrator < self.Integrator_min:
self.Integrator = self.Integrator_min
# Second method for regulating Integrator
# if self.measure_interval is not None:
# if self.Integrator * self.Ki > self.measure_interval:
# self.Integrator = self.measure_interval / self.Ki
# elif self.Integrator * self.Ki < -self.measure_interval:
# self.Integrator = -self.measure_interval / self.Ki
self.I_value = self.Integrator * self.Ki
# Calculate D-value
self.D_value = self.Kd * (self.error - self.Derivator)
self.Derivator = self.error
# Produce output form P, I, and D values
PID = self.P_value + self.I_value + self.D_value
return PID
def get_last_measurement(self):
"""
Retrieve the latest sensor measurement from InfluxDB
:rtype: None
"""
self.last_measurement_success = False
# Get latest measurement (from within the past minute) from influxdb
try:
if self.sensor_duration/60 < 1:
duration = 1
else:
duration = self.sensor_duration/60*1.5
self.last_measurement = read_last_influxdb(
INFLUXDB_HOST,
INFLUXDB_PORT,
INFLUXDB_USER,
INFLUXDB_PASSWORD,
INFLUXDB_DATABASE,
self.sensor_id,
self.measure_type,
duration)
if self.last_measurement:
measurement_list = list(self.last_measurement.get_points(
measurement=self.measure_type))
self.last_time = measurement_list[0]['time']
self.last_measurement = measurement_list[0]['value']
utc_dt = datetime.datetime.strptime(self.last_time.split(".")[0], '%Y-%m-%dT%H:%M:%S')
utc_timestamp = calendar.timegm(utc_dt.timetuple())
local_timestamp = str(datetime.datetime.fromtimestamp(utc_timestamp))
self.logger.debug("[PID {}] Latest {}: {} @ {}".format(
self.pid_id, self.measure_type,
self.last_measurement, local_timestamp))
self.last_measurement_success = True
else:
self.logger.warning("[PID {}] No data returned "
"from influxdb".format(self.pid_id))
except Exception as except_msg:
self.logger.exception("[PID {}] Failed to read "
"measurement from the influxdb "
"database: {}".format(self.pid_id,
except_msg))
def manipulate_relays(self):
"""
Activate a relay based on PID output (control variable) and whether
the manipulation directive is to raise, lower, or both.
:rtype: None
"""
# If there was a measurement able to be retrieved from
# influxdb database that was entered within the past minute
if self.last_measurement_success:
# Update setpoint if a method is selected
if self.method_id != '':
self.calculate_method_setpoint(self.method_id)
self.addSetpointInfluxdb(self.pid_id, self.set_point)
# Update PID and get control variable
self.control_variable = self.update(self.last_measurement)
#
# PID control variable positive to raise environmental condition
#
if self.direction in ['raise', 'both'] and self.raise_relay_id:
if self.control_variable > 0:
# Ensure the relay on duration doesn't exceed the set maximum
if (self.raise_max_duration and
self.control_variable > self.raise_max_duration):
self.raise_seconds_on = self.raise_max_duration
else:
self.raise_seconds_on = float("{0:.2f}".format(self.control_variable))
# Turn off lower_relay if active, because we're now raising
if self.lower_relay_id:
with session_scope(MYCODO_DB_PATH) as new_session:
relay = new_session.query(Relay).filter(
Relay.id == self.lower_relay_id).first()
if relay.is_on():
self.control.relay_off(self.lower_relay_id)
if self.raise_seconds_on > self.raise_min_duration:
# Activate raise_relay for a duration
self.logger.debug("[PID {}] Setpoint: {} "
"Output: {} to relay {}".format(
self.pid_id,
self.set_point,
self.control_variable,
self.raise_relay_id))
self.control.relay_on(self.raise_relay_id,
self.raise_seconds_on)
else:
self.control.relay_off(self.raise_relay_id)
#
# PID control variable negative to lower environmental condition
#
if self.direction in ['lower', 'both'] and self.lower_relay_id:
if self.control_variable < 0:
# Ensure the relay on duration doesn't exceed the set maximum
if (self.lower_max_duration and
abs(self.control_variable) > self.lower_max_duration):
self.lower_seconds_on = self.lower_max_duration
else:
self.lower_seconds_on = abs(float("{0:.2f}".format(self.control_variable)))
# Turn off raise_relay if active, because we're now lowering
if self.raise_relay_id:
with session_scope(MYCODO_DB_PATH) as new_session:
relay = new_session.query(Relay).filter(
Relay.id == self.raise_relay_id).first()
if relay.is_on():
self.control.relay_off(self.raise_relay_id)
if self.lower_seconds_on > self.lower_min_duration:
# Activate lower_relay for a duration
self.logger.debug("[PID {}] Setpoint: {} "
"Output: {} to relay {}".format(
self.pid_id,
self.set_point,
self.control_variable,
self.lower_relay_id))
self.control.relay_on(self.lower_relay_id,
self.lower_seconds_on)
else:
self.control.relay_off(self.lower_relay_id)
else:
if self.direction in ['raise', 'both'] and self.raise_relay_id:
self.control.relay_off(self.raise_relay_id)
if self.direction in ['lower', 'both'] and self.lower_relay_id:
self.control.relay_off(self.lower_relay_id)
def now_in_range(self, start_time, end_time):
"""
Check if the current time is between start_time and end_time
:return: 1 is within range, 0 if not within range
:rtype: int
"""
start_hour = int(start_time.split(":")[0])
start_min = int(start_time.split(":")[1])
end_hour = int(end_time.split(":")[0])
end_min = int(end_time.split(":")[1])
now_time = datetime.datetime.now().time()
now_time = now_time.replace(second=0, microsecond=0)
if ((start_hour < end_hour) or
(start_hour == end_hour and start_min < end_min)):
if now_time >= datetime.time(start_hour, start_min) and now_time <= datetime.time(end_hour, end_min):
return 1 # Yes now within range
else:
if now_time >= datetime.time(start_hour, start_min) or now_time <= datetime.time(end_hour, end_min):
return 1 # Yes now within range
return 0 # No now not within range
def calculate_method_setpoint(self, method_id):
with session_scope(MYCODO_DB_PATH) as new_session:
method = new_session.query(Method)
new_session.expunge_all()
new_session.close()
method_key = method.filter(Method.method_id == method_id)
method_key = method_key.filter(Method.method_order == 0).first()
method = method.filter(Method.method_id == method_id)
method = method.filter(Method.relay_id == None)
method = method.filter(Method.method_order > 0)
method = method.order_by(Method.method_order.asc()).all()
now = datetime.datetime.now()
# Calculate where the current time/date is within the time/date method
if method_key.method_type == 'Date':
for each_method in method:
start_time = datetime.datetime.strptime(each_method.start_time, '%Y-%m-%d %H:%M:%S')
end_time = end_time = datetime.datetime.strptime(each_method.end_time, '%Y-%m-%d %H:%M:%S')
if start_time < now < end_time:
start_setpoint = each_method.start_setpoint
if each_method.end_setpoint:
end_setpoint = each_method.end_setpoint
else:
end_setpoint = each_method.start_setpoint
setpoint_diff = abs(end_setpoint-start_setpoint)
total_seconds = (end_time-start_time).total_seconds()
part_seconds = (now-start_time).total_seconds()
percent_total = part_seconds/total_seconds
if start_setpoint < end_setpoint:
new_setpoint = start_setpoint+(setpoint_diff*percent_total)
else:
new_setpoint = start_setpoint-(setpoint_diff*percent_total)
self.logger.debug("[Method] Start: {} End: {}".format(
start_time, end_time))
self.logger.debug("[Method] Start: {} End: {}".format(
start_setpoint, end_setpoint))
self.logger.debug("[Method] Total: {} Part total: {} ({}%)".format(
total_seconds, part_seconds, percent_total))
self.logger.debug("[Method] New Setpoint: {}".format(
new_setpoint))
self.set_point = new_setpoint
return 0
# Calculate where the current Hour:Minute:Seconds is within the Daily method
elif method_key.method_type == 'Daily':
daily_now = datetime.datetime.now().strftime('%H:%M:%S')
daily_now = datetime.datetime.strptime(str(daily_now), '%H:%M:%S')
for each_method in method:
start_time = datetime.datetime.strptime(each_method.start_time, '%H:%M:%S')
end_time = end_time = datetime.datetime.strptime(each_method.end_time, '%H:%M:%S')
if start_time < daily_now < end_time:
start_setpoint = each_method.start_setpoint
if each_method.end_setpoint:
end_setpoint = each_method.end_setpoint
else:
end_setpoint = each_method.start_setpoint
setpoint_diff = abs(end_setpoint-start_setpoint)
total_seconds = (end_time-start_time).total_seconds()
part_seconds = (daily_now-start_time).total_seconds()
percent_total = part_seconds/total_seconds
if start_setpoint < end_setpoint:
new_setpoint = start_setpoint+(setpoint_diff*percent_total)
else:
new_setpoint = start_setpoint-(setpoint_diff*percent_total)
self.logger.debug("[Method] Start: {} End: {}".format(
start_time.strftime('%H:%M:%S'), end_time.strftime('%H:%M:%S')))
self.logger.debug("[Method] Start: {} End: {}".format(
start_setpoint, end_setpoint))
self.logger.debug("[Method] Total: {} Part total: {} ({}%)".format(
total_seconds, part_seconds, percent_total))
self.logger.debug("[Method] New Setpoint: {}".format(
new_setpoint))
self.set_point = new_setpoint
return 0
# Calculate sine y-axis value from the x-axis (seconds of the day)
elif method_key.method_type == 'DailySine':
new_setpoint = sine_wave_y_out(method_key.amplitude,
method_key.frequency,
method_key.shift_angle,
method_key.shift_y)
self.set_point = new_setpoint
return 0
# Calculate Bezier curve y-axis value from the x-axis (seconds of the day)
elif method_key.method_type == 'DailyBezier':
new_setpoint = bezier_curve_y_out(method_key.shift_angle,
(method_key.x0, method_key.y0),
(method_key.x1, method_key.y1),
(method_key.x2, method_key.y2),
(method_key.x3, method_key.y3))
self.set_point = new_setpoint
return 0
# Calculate the duration in the method based on self.method_start_time
elif method_key.method_type == 'Duration' and self.method_start_time != 'Ended':
seconds_from_start = (now-self.method_start_time).total_seconds()
total_sec = 0
previous_total_sec = 0
for each_method in method:
total_sec += each_method.duration_sec
if previous_total_sec <= seconds_from_start < total_sec:
row_start_time = float(self.method_start_time.strftime('%s'))+previous_total_sec
row_since_start_sec = (now-(self.method_start_time+datetime.timedelta(0, previous_total_sec))).total_seconds()
percent_row = row_since_start_sec/each_method.duration_sec
start_setpoint = each_method.start_setpoint
if each_method.end_setpoint:
end_setpoint = each_method.end_setpoint
else:
end_setpoint = each_method.start_setpoint
setpoint_diff = abs(end_setpoint-start_setpoint)
if start_setpoint < end_setpoint:
new_setpoint = start_setpoint+(setpoint_diff*percent_row)
else:
new_setpoint = start_setpoint-(setpoint_diff*percent_row)
self.logger.debug("[Method] Start: {} Seconds Since: {}".format(
self.method_start_time, seconds_from_start))
self.logger.debug("[Method] Start time of row: {}".format(
datetime.datetime.fromtimestamp(row_start_time)))
self.logger.debug("[Method] Sec since start of row: {}".format(
row_since_start_sec))
self.logger.debug("[Method] Percent of row: {}".format(
percent_row))
self.logger.debug("[Method] New Setpoint: {}".format(
new_setpoint))
self.set_point = new_setpoint
return 0
previous_total_sec = total_sec
# Duration method has ended, reset start_time locally and in DB
if self.method_start_time:
with session_scope(MYCODO_DB_PATH) as db_session:
mod_method = db_session.query(Method).filter(
Method.method_id == self.method_id)
mod_method = mod_method.filter(Method.method_order == 0).first()
mod_method.start_time = 'Ended'
db_session.commit()
self.method_start_time = 'Ended'
# Setpoint not needing to be calculated, use default setpoint
self.set_point = self.default_set_point
def addSetpointInfluxdb(self, pid_id, setpoint):
"""
Add a setpoint entry to InfluxDB
:rtype: None
"""
write_db = threading.Thread(
target=write_influxdb_value,
args=(self.logger, INFLUXDB_HOST,
INFLUXDB_PORT, INFLUXDB_USER,
INFLUXDB_PASSWORD, INFLUXDB_DATABASE,
'pid', pid_id, 'setpoint', setpoint,))
write_db.start()
def setPoint(self, set_point):
"""Initilize the setpoint of PID"""
self.set_point = set_point
self.Integrator = 0
self.Derivator = 0
def setIntegrator(self, Integrator):
"""Set the Integrator of the controller"""
self.Integrator = Integrator
def setDerivator(self, Derivator):
"""Set the Derivator of the controller"""
self.Derivator = Derivator
def setKp(self, P):
"""Set Kp gain of the controller"""
self.Kp = P
def setKi(self, I):
"""Set Ki gain of the controller"""
self.Ki = I
def setKd(self, D):
"""Set Kd gain of the controller"""
self.Kd = D
def getPoint(self):
return self.set_point
def getError(self):
return self.error
def getIntegrator(self):
return self.Integrator
def getDerivator(self):
return self.Derivator
def isRunning(self):
return self.running
def stopController(self):
self.thread_shutdown_timer = timeit.default_timer()
self.running = False
# Unset method start time
if self.method_id:
with session_scope(MYCODO_DB_PATH) as db_session:
mod_method = db_session.query(Method)
mod_method = mod_method.filter(Method.method_id == self.method_id)
mod_method = mod_method.filter(Method.method_order == 0).first()
mod_method.start_time = 'Ended'
db_session.commit()