I'm trying to display the values obtained from my heartbeat sensor in my Kivy App. I've tried using the data extraction method applied on the other sensors but it's not working for this sensor as it doesn't contain any functions.
I've tried multiple different approaches but they all haven't returned the desired output. Can someone please have a look at the sensor code and suggest some method to display the output in my kivy app.
Heartbeatsensot.py
import time
# Import the ADS1x15 module.
import Adafruit_ADS1x15
if __name__ == '__main__':
adc = Adafruit_ADS1x15.ADS1015()
# initialization
GAIN = 2/3
curState = 0
thresh = 525 # mid point in the waveform
P = 512
T = 512
stateChanged = 0
sampleCounter = 0
lastBeatTime = 0
firstBeat = True
secondBeat = False
Pulse = False
IBI = 600
rate = [0]*10
amp = 100
lastTime = int(time.time()*1000)
# Main loop. use Ctrl-c to stop the code
while True:
# read from the ADC
Signal = adc.read_adc(0, gain=GAIN) #TODO: Select the correct ADC channel. I have selected A0 here
curTime = int(time.time()*1000)
sampleCounter += curTime - lastTime; # # keep track of the time in mS with this variable
lastTime = curTime
N = sampleCounter - lastBeatTime; # # monitor the time since the last beat to avoid noise
#print N, Signal, curTime, sampleCounter, lastBeatTime
## find the peak and trough of the pulse wave
if Signal < thresh and N > (IBI/5.0)*3.0 : # # avoid dichrotic noise by waiting 3/5 of last IBI
if Signal < T : # T is the trough
T = Signal; # keep track of lowest point in pulse wave
if Signal > thresh and Signal > P: # thresh condition helps avoid noise
P = Signal; # P is the peak
# keep track of highest point in pulse wave
# NOW IT'S TIME TO LOOK FOR THE HEART BEAT
# signal surges up in value every time there is a pulse
if N > 250 : # avoid high frequency noise
if (Signal > thresh) and (Pulse == False) and (N > (IBI/5.0)*3.0) :
Pulse = True; # set the Pulse flag when we think there is a pulse
IBI = sampleCounter - lastBeatTime; # measure time between beats in mS
lastBeatTime = sampleCounter; # keep track of time for next pulse
if secondBeat : # if this is the second beat, if secondBeat == TRUE
secondBeat = False; # clear secondBeat flag
for i in range(0,10): # seed the running total to get a realisitic BPM at startup
rate[i] = IBI;
if firstBeat : # if it's the first time we found a beat, if firstBeat == TRUE
firstBeat = False; # clear firstBeat flag
secondBeat = True; # set the second beat flag
continue # IBI value is unreliable so discard it
# keep a running total of the last 10 IBI values
runningTotal = 0; # clear the runningTotal variable
for i in range(0,9): # shift data in the rate array
rate[i] = rate[i+1]; # and drop the oldest IBI value
runningTotal += rate[i]; # add up the 9 oldest IBI values
rate[9] = IBI; # add the latest IBI to the rate array
runningTotal += rate[9]; # add the latest IBI to runningTotal
runningTotal /= 10; # average the last 10 IBI values
BPM = 60000/runningTotal; # how many beats can fit into a minute? that's BPM!
print ('BPM: {}'.format(BPM))
if Signal < thresh and Pulse == True : # when the values are going down, the beat is over
Pulse = False; # reset the Pulse flag so we can do it again
amp = P - T; # get amplitude of the pulse wave
thresh = amp/2 + T; # set thresh at 50% of the amplitude
P = thresh; # reset these for next time
T = thresh;
if N > 2500 : # if 2.5 seconds go by without a beat
thresh = 512; # set thresh default
P = 512; # set P default
T = 512; # set T default
lastBeatTime = sampleCounter; # bring the lastBeatTime up to date
firstBeat = True; # set these to avoid noise
secondBeat = False; # when we get the heartbeat back
print ("no beats found")
time.sleep(0.005)
** the kivy app that I'm trying to add the readings to**
another.py file
from kivy.app import App
from kivy.uix.screenmanager import ScreenManager,Screen
from kivy.properties import ObjectProperty, StringProperty
from kivy.uix.boxlayout import BoxLayout
from kivy.clock import Clock
from kivy.uix.button import Button
from kivy.uix.label import Label
from kivy.lang import Builder
class MainScreen(Screen):
pass
class ScreenThermo(Screen):
def __init__(self,**kwargs):
super(ScreenThermo, self).__init__(**kwargs)
Clock.schedule_interval(self.displayHR, 10)
def displayHR(self,dt):
heartbeat = 'BPM: {}'.format(BPM)
pulse = heartbeat
self.manager.screen_thermo.ids.TempLabel.text = str(pulse)
def on_enter(self, *args):
self.__init__()
pass
class ScreenManagement(ScreenManager):
pass
presentation = Builder.load_file("heartk.kv")
class MenuApp(App):
def build(self):
return presentation
if __name__ == '__main__':
MenuApp().run()
.kv file
ScreenManagement:
id: screen_manager
screen_thermo: screen_thermo
MainScreen:
ScreenThermo:
id: screen_thermo
name: 'thermo'
manager: screen_manager
<MainScreen>:
name: "main"
Label:
text: "Welcome"
font_size: 60
halign: 'center'
valign: 'middle'
pos_hint: {'x': .01, 'y': .05}
on_touch_down: app.root.current = "thermo"
<ScreenThermo>:
Label:
text: " Pulse rate"
font_size: 50
pos: (35, 100)
Label:
id: TempLabel
font_size: 60
halign: 'center'
valign: 'middle'
I think you can accomplish what you want with a few minor modifications. First add a StringProperty to your ScreenThermo class, and in the on_enter() method start a thread to run your Heartbeatsensot code as:
from Heartbeatsensot import hearbeatsensot
class ScreenThermo(Screen):
BPM_string = StringProperty('BPM: Not Detected')
def on_enter(self, *args):
Thread(target=hearbeatsensot, args=(self,)).start()
And in your kv file, add a reference to the new StringProperty:
<ScreenThermo>:
Label:
text: " Pulse rate"
font_size: 50
pos: (35, 100)
Label:
id: TempLabel
text: root.BPM_string # references new StringProperty
font_size: 60
halign: 'center'
valign: 'middle'
Now you only need to put whatever you want to display in the TempLabel into the BPM_string property. To do that, change Heartbeatsensot.py to define a method that can be used in a Thread. Simply replace the if __name__ == '__main__': in that file to def hearbeatsensot(screenThermo): like this:
import time
# Import the ADS1x15 module.
import Adafruit_ADS1x15
def hearbeatsensot(screenThermo):
adc = Adafruit_ADS1x15.ADS1015()
# initialization
GAIN = 2/3
.
.
.
screenThermo.BPM_string = 'BPM: 65'
.
.
.
Then, within that method just use somethink like screenThermo.BPM_string = 'BPM: 65' (or whatever you want to set it to). The reference to BPM_string in the kv file will automatically set up a binding to update the TempLabel whenever BPM_string is modified.