Joy-it SEN-KY039HS User manual

3
SEN-KY039HS
Heartbeat sensor

Veröffentlicht: 21.05.2019 Copyright by Joy-IT 2
3SEN-KY039HS
TABLE OF CONTENT
1. Introducon
2. Use with the Raspberry Pi
2.1 Connecon
2.2 Installaon
2.3 Program example
3. Use with Arduino
3.1 Connecon
3.2 Program example
4. Further informaon
5. Support

Veröffentlicht: 21.05.2019 Copyright by Joy-IT 3
3SEN-KY039HS
1. Introduction
Dear customer,
Thank you for choosing our product.
In the following, we will show you what to consider during commissioning and use.
If you experience any unexpected problems during use, you are welcome to contact us.

Veröffentlicht: 21.05.2019 Copyright by Joy-IT 4
3SEN-KY039HS
2. Use with the Raspberry Pi
2.1 Connection
Since the heartbeat sensor is an analog sensor and the Raspberry Pi has no analog inputs, you will need to
use an analog-to-digital converter. For example our ADC COM-KY053ADC.
Raspberry Pi KY039HS ADC
3v3 (Pin1) VDD
GND (Pin 6) GND
SCL (Pin 5) SCL
SDA (Pin 3) SDA
Black A0
GND (Pin 14) Grey
3v3 (Pin 17) White

Veröffentlicht: 21.05.2019 Copyright by Joy-IT 5
3SEN-KY039HS
2.2 Installation
First, you need to install the library for the analog-to-digital converter.
This was published under the following link under the MIT license.
To install the library, simply enter the following command in the console:
In addion, you must enable I2C on your Raspberry Pi by entering the following command:
Now go to Interfacing Opons -> and acvate I2C.
2.3 Program example
sudo raspi-config
sudo pip3 install adafruit-circuitpython-ads1x15
import time
import board
import busio
import adafruit_ads1x15.ads1115 as ADS
from adafruit_ads1x15.analog_in import AnalogIn
# Create the I2C bus
i2c = busio.I2C(board.SCL, board.SDA)
# Create the ADC object using the I2C bus
ads = ADS.ADS1115(i2c)
# Create single-ended input on channels
chan0 = AnalogIn(ads, ADS.P0)
chan1 = AnalogIn(ads, ADS.P1)
chan2 = AnalogIn(ads, ADS.P2)
chan3 = AnalogIn(ads, ADS.P3)
if __name__ == '__main__':
# 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

Veröffentlicht: 21.05.2019 Copyright by Joy-IT 6
3SEN-KY039HS
2.3 Program example
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 = chan0.value #TODO: Select the correct ADC channel
curTime = int(time.time()*1000)
sampleCounter += curTime - lastTime; # keep track of time in mS with this variable
lastTime = curTime
N = sampleCounter - lastBeatTime; # monitor the time since last beat to avoid noise
## find the peak
if Signal < thresh and N > (IBI/5.0)*3.0 : # wait 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
# 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):
rate[i] = IBI;
if firstBeat :
firstBeat = False;
secondBeat = True;
continue
# 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];
runningTotal += rate[i];

Veröffentlicht: 21.05.2019 Copyright by Joy-IT 7
3SEN-KY039HS
2.3 Program example
3. Use with the Arduino
3.1 Connection
rate[9] = IBI;
runningTotal += rate[9];
runningTotal /= 10;
BPM = 60000/runningTotal;
print ('BPM: {}'.format(BPM))
if Signal < thresh and Pulse == True : # when the values are going down, the beat
is over
Pulse = False;
amp = P - T;
thresh = amp/2 + T;
P = thresh;
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)
Arduino KY039HS
5V White
GND Grey
A0 Black

Veröffentlicht: 21.05.2019 Copyright by Joy-IT 8
3SEN-KY039HS
3.2 Program example
////////////////////////////////////////////////////////////////////////
/// Copyright (c)2015 Dan Truong
/// Permission is granted to use this software under the MIT
/// licence, with my name and copyright kept in source code
/// http://http://opensource.org/licenses/MIT
///
/// KY039 Arduino Heartrate Monitor V1.0 (April 02, 2015)
////////////////////////////////////////////////////////////////////////
// German Comments by Joy-IT
int rawValue;
bool heartbeatDetected(int IRSensorPin, int delay)
{
static int maxValue = 0;
static bool isPeak = false;
bool result = false;
rawValue = analogRead(IRSensorPin);
// Hier wird der aktuelle Spannungswert am Fototransistor ausgelesen und in der rawValue-
Variable zwischengespeichert
rawValue *= (1000/delay);
// Sollte der aktuelle Wert vom letzten maximalen Wert zu weit abweichen
// (z.B. da der Finger neu aufgesetzt oder weggenommen wurde)
// So wird der MaxValue resetiert, um eine neue Basis zu erhalten.
if (rawValue * 4L < maxValue) { maxValue = rawValue * 0.8; } // Detect new peak
if (rawValue > maxValue - (1000/delay)) {
// Hier wird der eigentliche Peak detektiert. Sollte ein neuer RawValue groeßer sein
// als der letzte maximale Wert, so wird das als Spitze der aufgezeichnten Daten er-
kannt.
if (rawValue > maxValue) {
maxValue = rawValue;
}
// Zum erkannten Peak soll nur ein Herzschlag zugewiesen werden
if (isPeak == false) {
result = true;
}
isPeak = true;
} else if (rawValue < maxValue - (3000/delay)) {
isPeak = false;
// Hierbei wird der maximale Wert bei jeden Durchlauf
// etwas wieder herabgesetzt. Dies hat den Grund, dass
// nicht nur der Wert sonst immer stabil bei jedem Schlag
// gleich oder kleiner werden wuerde, sondern auch,
// falls der Finger sich minimal bewegen sollte und somit
// das Signal generell schwaecher werden wuerde.
maxValue-=(1000/delay);
}
return result;
}

Veröffentlicht: 21.05.2019 Copyright by Joy-IT 9
3SEN-KY039HS
int ledPin=13;
int analogPin=0;
void setup()
{
// Die eingebaute Arduino LED (Digital 13), wird hier zur Ausgabe genutzt
pinMode(ledPin,OUTPUT);
// Serielle Ausgabe Initialisierung
Serial.begin(9600);
Serial.println("Heartbeat Detektion Beispielcode.");
}
const int delayMsec = 60; // 100msec per sample
// Das Hauptprogramm hat zwei Aufgaben:
// - Wird ein Herzschlag erkannt, so blinkt die LED kurz aufgesetzt
// - Der Puls wird errechnet und auf der serriellen Ausgabe ausgegeben.
void loop()
{
static int beatMsec = 0;
int heartRateBPM = 0;
if (heartbeatDetected(analogPin, delayMsec)) {
heartRateBPM = 60000 / beatMsec;
// LED-Ausgabe bei Herzschlag
digitalWrite(ledPin,1);
// Serielle Datenausgabe
Serial.print("Puls erkannt: ");
Serial.println(heartRateBPM);
beatMsec = 0;
} else {
digitalWrite(ledPin,0);
}
delay(delayMsec);
beatMsec += delayMsec;
}

Veröffentlicht: 21.05.2019 Copyright by Joy-IT 10
3SEN-KY039HS
Our informaon and take-back obligaons according to the ElektroG
Symbol on electrical and electronic equipment
This crossed-out dustbin means that electrical and electronic equipment does not belong in the household
waste. You must return the old appliances to a collecon point. Before handing over waste baeries and
accumulators that are not enclosed by waste equipment must be separated from it.
Return opons
As an end user, you can return your old appliance (which essenally fulls the same funcon as the new
appliance purchased from us) free of charge for disposal when you purchase a new appliance. Small
appliances with no external dimensions greater than 25 cm can be disposed of in normal household quanes
independently of the purchase of a new appliance.
Possibility of return at our company locaon during opening hours
Simac GmbH, Pascalstr. 8, D-47506 Neukirchen-Vluyn
Possibility of return in your area
We will send you a parcel stamp with which you can return the device to us free of charge. Please contact us
by e-mail at [e-mail] or by telephone.
Informaon on packaging
If you do not have suitable packaging material or do not wish to use your own, please contact us and we will
send you suitable packaging.
4. Further Information

Veröffentlicht: 21.05.2019 Copyright by Joy-IT 11
3SEN-KY039HS
5. Support
We are also there for you aer your purchase. If any quesons remain open or problems arise, we are
also available by e-mail, telephone and cket support system.
E-Mail: [e-mail]
Ticket-System: hp://support.joy-it.net
Phone: [phone] – 66 (10- 17 o‘clock)
For more informaon visit our website:
www.joy-it.net