class Agitator(object):
'''Class for controlling the EXPRES fiber agitator
Inputs
------
comport : str
The hardware COM Port for the Roboclaw motor controller
Public Methods
--------------
start(exp_time, timeout, rot1, rot2):
Threaded agitation
start_agitation(exp_time, rot1, rot2):
Unthreaded agitation
stop():
Stop either threaded or unthreaded agitation
stop_agitation():
Hard-stop agitation but will not close thread
'''
def __init__(self, comport=__DEFAULT_PORT__):
self._rc = Roboclaw(comport=comport,
rate=__DEFAULT_BAUD_RATE__,
addr=__DEFAULT_ADDR__,
timeout=__DEFAULT_TIMEOUT__,
retries=__DEFAULT_RETRIES__,
inter_byte_timeout=__DEFAULT_INTER_BYTE_TIMEOUT__)
# Create a logger for the agitator
self.logger = logging.getLogger('expres_agitator')
self.logger.setLevel(logging.DEBUG)
# Create file handler to log all messages
try:
fh = logging.handlers.TimedRotatingFileHandler(
'C:/Users/admin/agitator_logs/agitator.log',
when='D',
interval=1,
utc=True,
backupCount=5)
except FileNotFoundError:
fh = logging.handlers.TimedRotatingFileHandler('agitator.log',
when='D',
interval=1,
utc=True,
backupCount=5)
fh.setLevel(logging.DEBUG)
# Create console handler to log info messages
ch = logging.StreamHandler()
ch.setLevel(logging.INFO)
# create formatter and add it to the handlers
formatter = logging.Formatter(
'%(asctime)s - %(name)s - %(levelname)s - %(message)s')
fh.setFormatter(formatter)
ch.setFormatter(formatter)
# add the handlers to the logger
self.logger.addHandler(fh)
self.logger.addHandler(ch)
self.thread = None # In case stop() is called before a thread is created
self.stop_event = Event() # Used for stopping threads
self.stop_agitation() # Just to make sure
def __del__(self):
'''
When the object is deleted, make sure all threads are closed and
agitator is stopped. Unfortunately, these actions cannot be logged
because the logger closes by the time __del__ is called...
'''
self.stop(verbose=False)
self.stop_agitation(verbose=False)
def threaded_agitation(self, exp_time, timeout, **kwargs):
'''Threadable function allowing stop event'''
self.logger.info(
'Starting agitator thread for {}s exposure with {}s timeout'.
format(exp_time, timeout))
self.start_agitation(exp_time, **kwargs)
t = 0
start_time = time.time()
while not self.stop_event.is_set() and t < timeout:
time.sleep(1)
t = time.time() - start_time
self.logger.info('{}/{}s for {}s exposure. I1: {}, I2: {}'.format(
round(t, 1), timeout, exp_time, self.current1, self.current2))
self.stop_agitation()
self.stop_event.clear() # Allow for future agitation events
def start(self, exp_time=60.0, timeout=None, **kwargs):
'''
Start a thread that starts agitation and stops if a stop event is
called or if the timeout is reached
'''
self.stop() # To close any previously opened threads
if timeout is None: # Allow for some overlap time
timeout = exp_time + 10.0
self.thread = Thread(target=self.threaded_agitation,
args=(exp_time, timeout),
kwargs=kwargs)
self.thread.start()
def stop(self, verbose=True):
'''Stop the agitation thread if it is running'''
if self.thread is not None and self.thread.is_alive():
while self.voltage1 > 0 or self.voltage2 > 0:
if verbose:
self.logger.info('Attempting to stop threaded agitation')
self.stop_event.set()
self.thread.join(2)
if self.voltage1 > 0 or self.voltage2 > 0:
# As a backup in case something went wrong
if verbose:
self.logger.error(
'Something went wrong when trying to stop threaded agitation. Forcing agitator to stop.'
)
self.stop_agitation()
def start_agitation(self, exp_time=60.0, rot=None):
'''Set the motor voltages for the given number of rotations in exp_time'''
if exp_time <= 0:
self.logger.warning(
'Non-positive exposure time given to agitator object')
self.stop_agitation()
return
if rot is None:
rot = 0.5 * exp_time
if rot <= 0:
self.logger.warning(
'Non-positive rotation number given to agitator object')
self.stop_agitation()
return
freq1 = rot / exp_time
freq2 = 0.9 * rot / exp_time
self._freq = freq1
self.logger.info('Starting agitation at approximately {} Hz'.format(
self._freq))
self.set_voltage1(Motor1.calc_voltage(self.battery_voltage, freq1))
self.set_voltage2(Motor2.calc_voltage(self.battery_voltage, freq2))
def stop_agitation(self, verbose=True):
'''Set both motor voltages to 0'''
if verbose:
self.logger.info('Stopping agitation')
self.set_voltage(0)
self._freq = 0
def set_voltage(self, voltage):
'''Set both motor voltages to the given voltage'''
self.set_voltage1(voltage)
self.set_voltage2(voltage)
# Getter for the frequency
def get_freq(self):
self.logger.info('Requesting frequency')
return self._freq
# Getters and setters for the motor voltages
def get_voltage1(self):
return self._voltage1
def set_voltage1(self, voltage):
battery_voltage = self.battery_voltage
if abs(voltage) > battery_voltage:
voltage = np.sign(voltage) * battery_voltage
if voltage >= 0:
self._rc.ForwardM1(int(voltage / battery_voltage * 127))
else:
self._rc.BackwardM1(int(-voltage / battery_voltage * 127))
self._voltage1 = voltage
voltage1 = property(get_voltage1, set_voltage1)
def get_voltage2(self):
return self._voltage2
def set_voltage2(self, voltage):
battery_voltage = self.battery_voltage
if abs(voltage) > battery_voltage:
voltage = np.sign(voltage) * battery_voltage
if voltage >= 0:
self._rc.ForwardM2(int(voltage / battery_voltage * 127))
else:
self._rc.BackwardM2(int(-voltage / battery_voltage * 127))
self._voltage2 = voltage
voltage2 = property(get_voltage2, set_voltage2)
def get_max_voltage(self):
return self._rc.ReadMinMaxMainVoltages()[2] / 10
def set_max_voltage(self, voltage):
self._rc.SetMainVoltages(int(self.min_voltage * 10), int(voltage * 10))
max_voltage = property(get_max_voltage, set_max_voltage)
def get_min_voltage(self):
return self._rc.ReadMinMaxMainVoltages()[1] / 10
def set_min_voltage(self, voltage):
self._rc.SetMainVoltages(int(voltage * 10), int(self.max_voltage * 10))
min_voltage = property(get_min_voltage, set_min_voltage)
# Getter for the motor controller power source voltage
def get_battery_voltage(self):
return self._rc.ReadMainBatteryVoltage()[1] / 10
battery_voltage = property(get_battery_voltage)
# Getters and setters for the motor currents
def get_current1(self):
return self._rc.ReadCurrents()[1] / 100
current1 = property(get_current1)
def get_current2(self):
return self._rc.ReadCurrents()[2] / 100
current2 = property(get_current2)
def get_max_current1(self):
return self._rc.ReadM1MaxCurrent()[1] / 100
def set_max_current1(self, current):
self._rc.SetM1MaxCurrent(current)
max_current1 = property(get_max_current1, set_max_current1)
def get_max_current2(self):
return self._rc.ReadM2MaxCurrent()[1] / 100
def set_max_current2(self, current):
self._rc.SetM2MaxCurrent(current)
max_current2 = property(get_max_current2, set_max_current2)
class Motor(object):
'''
Motor class contains the methods necessary to send commands to the motor controllers
for the corner and drive motors. There are many other ways of commanding the motors
from the RoboClaw, we suggest trying to write your own Closed loop feedback method for
the drive motors!
'''
def __init__(self,config):
super(Motor,self).__init__(config)
self.rc = Roboclaw( config['CONTROLLER_CONFIG']['device'],
config['CONTROLLER_CONFIG']['baud_rate']
)
self.rc.Open()
self.address = config['MOTOR_CONFIG']['controller_address']
self.accel = [0] * 10
self.qpps = [None] * 10
self.err = [None] * 5
version = 1
for address in self.address:
version = version & self.rc.ReadVersion(address)[0]
print(self.rc.ReadVersion(address)[0])
if version != 0:
print("[Motor__init__] Sucessfully connected to RoboClaw motor controllers")
else:
print("-----")
raise Exception("Unable to establish connection to Roboclaw motor controllers")
self.enc_min =[]
self.enc_max =[]
for address in self.address:
self.rc.SetMainVoltages(address,
int(config['BATTERY_CONFIG']['low_voltage']*10),
int(config['BATTERY_CONFIG']['high_voltage']*10)
)
if address == 131 or address == 132:
self.rc.SetM1MaxCurrent(address, int(config['MOTOR_CONFIG']['max_corner_current']*100))
self.rc.SetM2MaxCurrent(address, int(config['MOTOR_CONFIG']['max_corner_current']*100))
self.enc_min.append(self.rc.ReadM1PositionPID(address)[-2])
self.enc_min.append(self.rc.ReadM2PositionPID(address)[-2])
self.enc_max.append(self.rc.ReadM1PositionPID(address)[-1])
self.enc_max.append(self.rc.ReadM2PositionPID(address)[-1])
else:
self.rc.SetM1MaxCurrent(address, int(config['MOTOR_CONFIG']['max_drive_current']*100))
self.rc.SetM2MaxCurrent(address, int(config['MOTOR_CONFIG']['max_drive_current']*100))
self.rc.ResetEncoders(address)
for address in self.address:
self.rc.WriteNVM(address)
for address in self.address:
self.rc.ReadNVM(address)
voltage = self.rc.ReadMainBatteryVoltage(0x80)[1]/10.0
if voltage >= config['BATTERY_CONFIG']['low_voltage']:
print("[Motor__init__] Voltage is safe at: ",voltage, "V")
else:
raise Exception("Unsafe Voltage of" + voltage + " Volts")
i = 0
for address in self.address:
self.qpps[i] = self.rc.ReadM1VelocityPID(address)[4]
self.accel[i] = int(self.qpps[i]*2)
self.qpps[i+1] = self.rc.ReadM2VelocityPID(address)[4]
self.accel[i+1] = int(self.qpps[i]*2)
i+=2
self.errorCheck()
def cornerToPosition(self,tick):
'''
Method to send position commands to the corner motor
:param list tick: A list of ticks for each of the corner motors to
move to, if tick[i] is 0 it instead stops that motor from moving
'''
speed, accel = 1000,2000 #These values could potentially need tuning still
self.errorCheck()
for i in range(4):
index = int(math.ceil((i+1)/2.0)+2)
if tick[i]:
if (i % 2): self.rc.SpeedAccelDeccelPositionM2(self.address[index],accel,speed,accel,tick[i],1)
else: self.rc.SpeedAccelDeccelPositionM1(self.address[index],accel,speed,accel,tick[i],1)
else:
if not (i % 2): self.rc.ForwardM1(self.address[index],0)
else: self.rc.ForwardM2(self.address[index],0)
def sendMotorDuty(self, motorID, speed):
'''
Wrapper method for an easier interface to control the drive motors,
sends open-loop commands to the motors
:param int motorID: number that corresponds to each physical motor
:param int speed: Speed for each motor, range from 0-127
'''
self.errorCheck()
addr = self.address[int(motorID/2)]
if speed > 0:
if not motorID % 2: command = self.rc.ForwardM1
else: command = self.rc.ForwardM2
else:
if not motorID % 2: command = self.rc.BackwardM1
else: command = self.rc.BackwardM2
speed = abs(int(speed * 127))
return command(addr,speed)
def killMotors(self):
'''
Stops all motors on Rover
'''
for i in range(5):
self.rc.ForwardM1(self.address[i],0)
self.rc.ForwardM2(self.address[i],0)
def errorCheck(self):
'''
Checks error status of each motor controller, returns 0 if any errors occur
'''
for i in range(5):
self.err[i] = self.rc.ReadError(self.address[i])[1]
for error in self.err:
if error:
self.killMotors()
self.writeError()
raise Exception("Motor controller Error", error)
return 1
def writeError(self):
'''
Writes the list of errors to a text file for later examination
'''
f = open('errorLog.txt','a')
errors = ','.join(str(e) for e in self.err)
f.write('\n' + 'Errors: ' + '[' + errors + ']' + ' at: ' + str(datetime.datetime.now()))
f.close()