class StrainSensor(Sensor):
'''Class used to handle load cell type sensors. Extends Sensor class '''
def __init__(self,
deviceSN,
channelNo,
dataInterval,
refreshPeriod,
sensorName=None):
'''
Constructor for strain sensor phidgets. Takes standard Sensor arguments
'''
self.channelNo = channelNo
self.sensorUnits = "Kg"
self.useCallibration = False
self.gradient = 1
self.intercept = 0
Sensor.__init__(self, deviceSN, dataInterval, refreshPeriod,
sensorName)
def attachSensor(self):
'''
Connects the strain sensor to the application
'''
self.channel = VoltageRatioInput()
self.channel.setDeviceSerialNumber(self.deviceSN)
self.channel.setChannel(self.channelNo)
self.channel.openWaitForAttachment(100)
print("\n***** {} Sensor Attached *****".format(self.sensorName))
self.attached = True
self.channel.setDataInterval(self.dataInterval)
self.channel.setBridgeGain(0x8)
def activateDataListener(self):
'''
Sets up the event which triggers when the sensor updates its utput values
'''
self.startTime = time.time()
def onSensorValueChange(channelObject, voltageRatio):
rawTime = time.time()
deltaTime = rawTime - self.startTime
if self.useCallibration:
voltageRatio = voltageRatio * self.gradient + self.intercept
self.dataQ.put([voltageRatio, deltaTime, rawTime])
self.channel.setOnVoltageRatioChangeHandler(onSensorValueChange)
def setCallibration(self, gradient, intercept):
'''
Used to give the sensor callibration values.
'''
self.gradient = gradient
self.intercept = intercept
self.useCallibration = True
class VoltageRatioSensor(Sensor):
'''Class used to handle any sensor which uses a ratiometric voltage input '''
def __init__(self,
deviceSN,
channelNo,
dataInterval,
refreshPeriod,
sensorType,
sensorName=None):
'''
Connects the sensor to the application
'''
self.channelNo = channelNo
self.sensorType = sensorType
self.sensorUnits = None
Sensor.__init__(self, deviceSN, dataInterval, refreshPeriod,
sensorName)
def attachSensor(self):
'''
Connects the sensor to the application
'''
self.channel = VoltageRatioInput()
self.channel.setDeviceSerialNumber(self.deviceSN)
self.channel.setChannel(self.channelNo)
self.channel.openWaitForAttachment(100)
print("\n***** {} Sensor Attached *****".format(self.sensorName))
self.attached = True
self.channel.setSensorType(self.sensorType)
self.channel.setDataInterval(self.dataInterval)
self.sensorUnits = self.channel.getSensorUnit().symbol
def activateDataListener(self):
'''
Sets up the event which triggers when the sensor updates its outputs
'''
self.startTime = time.time()
def onSensorValueChange(channelObject, sensorVlue, sensorUnit):
rawTime = time.time()
deltaTime = rawTime - self.startTime
self.dataQ.put(
[channelObject.getSensorValue(), deltaTime, rawTime])
self.channel.setOnSensorChangeHandler(onSensorValueChange)
class jigCurrent(object):
'''current sensor'''
def __init__(self, provider, channel):
self.ai = VoltageRatioInput()
self.ai.setDeviceSerialNumber(provider)
self.ai.setChannel(channel)
self.ai.setOnAttachHandler(self._attached)
self.ai.openWaitForAttachment(1000)
def _attached(self, event):
self.ai.setSensorType(VoltageRatioSensorType.SENSOR_TYPE_1122_DC)
self.ai.setDataInterval(100)
self.ai.setVoltageRatioChangeTrigger(0)
@property
def current(self):
return self.ai.getSensorValue()
@property
def unitInfo(self):
return self.ai.getSensorUnit()
def main():
voltageRatioInput0 = VoltageRatioInput()
voltageRatioInput0.setIsHubPortDevice(True)
voltageRatioInput0.setHubPort(0)
print(*[x for x in voltageRatioInput0.__dir__() if "DataInterval" in x],
sep="\n")
voltageRatioInput0.setOnVoltageRatioChangeHandler(onVoltageRatioChange)
voltageRatioInput0.openWaitForAttachment(5000)
print(voltageRatioInput0.getMinDataInterval(),
voltageRatioInput0.getMaxDataInterval())
voltageRatioInput0.setDataInterval(100)
voltageRatioInput0.setSensorValueChangeTrigger(0.01)
try:
input("Press Enter to Stop\n")
except (Exception, KeyboardInterrupt):
pass
voltageRatioInput0.close()
def main():
port = "/dev/ttyACM0"
try:
print("Trying Arduino Set Up...")
s1 = serial.Serial(port, 9600)
if s1.name == port:
current_time_struct = time.localtime()
current_time = "{}:{}:{}".format(current_time_struct[3],
current_time_struct[4],
current_time_struct[5])
s1.flushInput()
lines = []
time.sleep(1.5)
try:
with open("hx711_output.csv", newline='') as csvFile:
print("Successfully found CSV file.\n")
reader = csv.reader(csvFile)
except:
print("File does not exist, creating file.\n")
with open("hx711_output.csv", 'w') as csvFile:
writer = csv.writer(csvFile)
writer.writerows(["Time", "Weight"])
with open("hx711_output.csv", 'a') as csvFile:
print("Successfully opened CSV file for writing\n")
writer = csv.writer(csvFile)
while 1:
current_time_struct = time.localtime()
current_time = '{}:{}:{}'.format(current_time_struct[3],
current_time_struct[4],
current_time_struct[5])
if s1.in_waiting > 0:
num_bytes = s1.read(1)
print(num_bytes)
weight = s1.read(num_bytes)
print(weight)
#writer.writerows([current_time, weight])
except:
try:
print("Arduino Set Up Failed, Trying Phidget...")
ch = VoltageRatioInput()
ch.setOnAttachHandler(onAttachHandler)
ch.setOnVoltageRatioChangeHandler(onVoltageRatioChangeHandler)
ch.voltageRatio = 0.0
try:
print("Waiting for Attachment")
ch.openWaitForAttachment(10000)
ch.setDataInterval(10)
except PhidgetException as e:
print("Attachment Timed Out")
#time.sleep(10)
#Checks to see if enter has been pressed
readin = sys.stdin.readline()
while readin != "\n":
time.sleep(1)
ch.close()
return 0
except PhidgetException as e:
sys.stderr.write("\nExiting with error(s)...")
DisplayError(e)
traceback.print_exc()
print("Cleaning up...")
ch.close()
return 1
except RunTimeError as e:
sys.stderr.write("Runtime Error: \n\t" + e)
traceback.print_exc()
return 1
def VoltageRatioChangeHandlerA(e, voltageRatio):
global a
a = voltageRatio
#
def VoltageRatioChangeHandlerB(e, voltageRatio):
global b
b = voltageRatio
#
start = time.time()
# Bridge (DAQ1500) is enabled by default so no need to enable it.
# Some functions are Boolean. 1 means enabled. Unit of time is ms.
ch.setOnVoltageRatioChangeHandler(VoltageRatioChangeHandlerA)
ch.setHubPort(1)
ch.setIsHubPortDevice(1)
ch.openWaitForAttachment(5000)
ch.setDataInterval(500) #minimum 1
#
ch2.setOnVoltageRatioChangeHandler(VoltageRatioChangeHandlerB)
ch2.setHubPort(0)
ch2.setChannel(0)
ch2.openWaitForAttachment(5000)
ch2.setDataInterval(500) # minimum 20
################################
X=[]
Y=[]
################################
while 1:
F= b*S+CS # Force # "b" is signal from load cell
D= a*L+CL #Displacement or position. "a" comes from lvdt
# in this example, mechanical zero and stage zero coincide. Equation for D
# may need to be modified.