Ryan Williams / Breath

breath sensor library

windSensor.cpp@1:d07f80ef7abc, 2016-12-11 (annotated)

Committer:
otis22894
Date:
Sun Dec 11 21:12:18 2016 +0000
Revision:
1:d07f80ef7abc
Parent:
0:397523d4133e 
First commit

Who changed what in which revision?

UserRevisionLine numberNew contents of line
otis22894 0:397523d4133e 1 #include "windSensor.h"
otis22894 0:397523d4133e 2
otis22894 1:d07f80ef7abc 3 windSensor :: windSensor(PinName p, NeoStrip *_strip, PinName p2, PinName p3)
otis22894 1:d07f80ef7abc 4 : sensor(p), strip(_strip), barometer(p2, p3, (0x60<<1))
otis22894 0:397523d4133e 5 {
otis22894 1:d07f80ef7abc 6 //thresh = sensor.read()*1.4;
otis22894 1:d07f80ef7abc 7 thresh = 0.63;
otis22894 0:397523d4133e 8 isBreathing = false;
otis22894 0:397523d4133e 9 breathCount = 0;
otis22894 0:397523d4133e 10 strip->setBrightness(0.1);
otis22894 1:d07f80ef7abc 11 strip->clear();
otis22894 1:d07f80ef7abc 12 spike = false;
otis22894 1:d07f80ef7abc 13 barometer.config();
otis22894 1:d07f80ef7abc 14 wait(0.1);
otis22894 1:d07f80ef7abc 15 int i;
otis22894 1:d07f80ef7abc 16 float base = 0.0;
otis22894 1:d07f80ef7abc 17 for(i = 0; i<10; i++) {
otis22894 1:d07f80ef7abc 18 float tempPress = barometer.getPressure();
otis22894 1:d07f80ef7abc 19 base = base + tempPress;
otis22894 1:d07f80ef7abc 20 //printf("%12.5f\n",val);
otis22894 1:d07f80ef7abc 21 }
otis22894 1:d07f80ef7abc 22 base = base/10.0; //get first pressure baseline reading
otis22894 1:d07f80ef7abc 23 pressure_threshold = 0.96*base;
otis22894 0:397523d4133e 24 }
otis22894 0:397523d4133e 25
otis22894 0:397523d4133e 26 void windSensor::startReading()
otis22894 0:397523d4133e 27 {
otis22894 1:d07f80ef7abc 28 breathReader.attach(this, &windSensor::sample, .02f);
otis22894 0:397523d4133e 29 //volatile float a = sensor;
otis22894 0:397523d4133e 30 //printf("\nwindsensor reads: %f", a);
otis22894 0:397523d4133e 31 //printf("\nthresh is: %f", thresh);
otis22894 0:397523d4133e 32 }
otis22894 0:397523d4133e 33
otis22894 0:397523d4133e 34 void windSensor::stopReading()
otis22894 0:397523d4133e 35 {
otis22894 0:397523d4133e 36 breathReader.detach();
otis22894 0:397523d4133e 37 __enable_irq();
otis22894 0:397523d4133e 38 }
otis22894 0:397523d4133e 39
otis22894 0:397523d4133e 40 void windSensor::reset()
otis22894 0:397523d4133e 41 {
otis22894 0:397523d4133e 42 //thresh = sensor*1.2; //set thresh to an appropraite percent above the baseline reading
otis22894 0:397523d4133e 43 //Breath = false; // true victims breath crosses thresh
otis22894 0:397523d4133e 44 isBreathing = false; //true if we get 3 'Breaths' in the calling programs time window-->means victim is breathing
otis22894 0:397523d4133e 45 breathCount = 0;
otis22894 0:397523d4133e 46 }
otis22894 0:397523d4133e 47
otis22894 0:397523d4133e 48 //call this member function to see if victim is breathing
otis22894 0:397523d4133e 49 bool windSensor::breathDetected()
otis22894 0:397523d4133e 50 {
otis22894 0:397523d4133e 51 return isBreathing; //only return positive if we get the critical number of Breaths in the given time window
otis22894 0:397523d4133e 52 }
otis22894 0:397523d4133e 53
otis22894 0:397523d4133e 54
otis22894 0:397523d4133e 55 // THIS IS THE TIMER 2 INTERRUPT SERVICE ROUTINE.
otis22894 0:397523d4133e 56 // Timer 2 makes sure that we take a reading every 2 miliseconds
otis22894 0:397523d4133e 57 void windSensor:: sample() // triggered when Timer2 counts to 124
otis22894 0:397523d4133e 58 {
otis22894 0:397523d4133e 59 __disable_irq();
otis22894 0:397523d4133e 60 float readVal = sensor.read(); // sample
otis22894 1:d07f80ef7abc 61 //printf("%f\n",readVal);
otis22894 0:397523d4133e 62 //check to see if victim is breathing at all above natural variation in sensor noise
otis22894 0:397523d4133e 63 if(readVal >= thresh) {
otis22894 0:397523d4133e 64 breathCount++; //increment global counter
otis22894 1:d07f80ef7abc 65 printf("Found breath");
otis22894 0:397523d4133e 66 }
otis22894 0:397523d4133e 67 if(breathCount >= 3) { //should set this higher if want more certainty in victim breathing
otis22894 0:397523d4133e 68 isBreathing = true;
otis22894 0:397523d4133e 69 }
otis22894 0:397523d4133e 70 __enable_irq(); // enable interrupts again
otis22894 0:397523d4133e 71 //return;
otis22894 0:397523d4133e 72 }
otis22894 0:397523d4133e 73
otis22894 0:397523d4133e 74 template<typename T>
otis22894 0:397523d4133e 75 void pop_front(std::vector<T>& vec)
otis22894 0:397523d4133e 76 {
otis22894 0:397523d4133e 77 //assert(!vec.empty());
otis22894 0:397523d4133e 78 vec.erase(vec.begin());
otis22894 0:397523d4133e 79 }
otis22894 0:397523d4133e 80
otis22894 0:397523d4133e 81 float windSensor::give_breath(void)
otis22894 0:397523d4133e 82 {
otis22894 1:d07f80ef7abc 83 spike = false;
otis22894 0:397523d4133e 84 strip->initialize();
otis22894 0:397523d4133e 85 c.clear();
otis22894 0:397523d4133e 86 t.reset();
otis22894 0:397523d4133e 87 q.reset();
otis22894 0:397523d4133e 88 //float a = 0.0;
otis22894 1:d07f80ef7abc 89
otis22894 0:397523d4133e 90 float d = 0.0; //return time for fractional breathes
otis22894 0:397523d4133e 91 float e = 0.0;
otis22894 0:397523d4133e 92 int i;
otis22894 0:397523d4133e 93 float thresh;
otis22894 0:397523d4133e 94 /*for(i = 0; i<20; i++) {
otis22894 0:397523d4133e 95 float val = sensor.read();
otis22894 0:397523d4133e 96 a = a + val;
otis22894 0:397523d4133e 97 //printf("%12.5f\n",val);
otis22894 0:397523d4133e 98 }
otis22894 0:397523d4133e 99 a = a/20.0; //get first baseline reading
otis22894 0:397523d4133e 100 //thresh = a*3.0; //theshold to start breathe timer (ideal multiplier is between 2-3)*/
otis22894 0:397523d4133e 101 thresh = 0.63;
otis22894 0:397523d4133e 102 //printf("thresh:%f\n",thresh);
otis22894 0:397523d4133e 103 t.start();
otis22894 0:397523d4133e 104 while(1) {
otis22894 0:397523d4133e 105 if(t.read() <= 3.0) {
otis22894 0:397523d4133e 106 wait(0.1); //necessary to give sensor time to be polled
otis22894 0:397523d4133e 107 float val = sensor.read();
otis22894 0:397523d4133e 108 //printf("%15.5f\n",val);
otis22894 0:397523d4133e 109 if(val > thresh) {
otis22894 0:397523d4133e 110 //printf("Made it here\n");
otis22894 0:397523d4133e 111 q.start();
otis22894 0:397523d4133e 112 for(i = 0; i<10; i++) {
otis22894 0:397523d4133e 113 c.push_back(val);
otis22894 0:397523d4133e 114 }
otis22894 0:397523d4133e 115 for(i=0; i<10; i++) {
otis22894 0:397523d4133e 116 e = e + c[i];
otis22894 0:397523d4133e 117 }
otis22894 0:397523d4133e 118 e = e/10.0; //provides slope of 10 most recent samples
otis22894 1:d07f80ef7abc 119 float oldTimerVal = 0, pressure;
otis22894 0:397523d4133e 120 float timerVal = q.read();
otis22894 0:397523d4133e 121 while( (e > thresh) && (timerVal < 1.0)) {
otis22894 0:397523d4133e 122
otis22894 0:397523d4133e 123 pop_front(c);//remove the oldest element
otis22894 0:397523d4133e 124 c.push_back(sensor.read());
otis22894 0:397523d4133e 125 for(i=0; i<10; i++) {
otis22894 0:397523d4133e 126 e = e + c[i];
otis22894 0:397523d4133e 127 }
otis22894 0:397523d4133e 128 e = e/10.0; //provides slope of 10 most recent samples
otis22894 0:397523d4133e 129 timerVal = q.read();
otis22894 0:397523d4133e 130 if(timerVal >= oldTimerVal + 0.25){
otis22894 0:397523d4133e 131 strip->progress(timerVal);
otis22894 0:397523d4133e 132 oldTimerVal = timerVal;
otis22894 0:397523d4133e 133 }
otis22894 1:d07f80ef7abc 134
otis22894 1:d07f80ef7abc 135 pressure = barometer.getPressure();
otis22894 1:d07f80ef7abc 136 //printf("Pressure: %f\n", pressure);
otis22894 1:d07f80ef7abc 137 if(pressure < pressure_threshold){
otis22894 1:d07f80ef7abc 138 spike = true;
otis22894 1:d07f80ef7abc 139 //printf("SPIKE");
otis22894 1:d07f80ef7abc 140 }
otis22894 1:d07f80ef7abc 141
otis22894 0:397523d4133e 142 }
otis22894 0:397523d4133e 143 d = q.read();
otis22894 0:397523d4133e 144 if(q.read() > 1.0) { //breathe was greater than thresh and lasted more than 1 sec
otis22894 0:397523d4133e 145 t.stop(); q.stop();
otis22894 0:397523d4133e 146 strip->progress(1);
otis22894 0:397523d4133e 147 return 1.0; //full breath
otis22894 0:397523d4133e 148 } else {
otis22894 0:397523d4133e 149 t.stop(); q.stop();
otis22894 0:397523d4133e 150 return d; //partial breath
otis22894 0:397523d4133e 151 }
otis22894 0:397523d4133e 152 }
otis22894 0:397523d4133e 153 } else {
otis22894 0:397523d4133e 154 t.stop(); q.stop();
otis22894 0:397523d4133e 155 return 0.0; //no breath in 3 seconds
otis22894 0:397523d4133e 156 }
otis22894 0:397523d4133e 157 }
otis22894 1:d07f80ef7abc 158 }
otis22894 0:397523d4133e 159
otis22894 1:d07f80ef7abc 160 //call this member function to see if there is a pressure spike
otis22894 1:d07f80ef7abc 161 bool windSensor::pressureSpikeDetected()
otis22894 1:d07f80ef7abc 162 {
otis22894 1:d07f80ef7abc 163 return spike; //return true if spike occured during give_breath.
otis22894 0:397523d4133e 164 }
otis22894 0:397523d4133e 165
otis22894 0:397523d4133e 166