Init

pumpkin-motion-trigger.ino

@@ -0,0 +1,166 @@
+class HCSR04
+{
+  int pinTrigger;
+  int pinEcho;
+  double soundMetresPerMillisecond = 0.343;
+
+  public:
+  HCSR04(int pinTrigger, int pinEcho)
+  {
+    this->pinTrigger = pinTrigger;
+    this->pinEcho = pinEcho;
+    
+    pinMode(this->pinTrigger, OUTPUT);
+    pinMode(this->pinEcho, INPUT);
+  }
+
+  double getMilliseconds()
+  {
+    digitalWrite(this->pinTrigger, LOW);
+    delayMicroseconds(10);
+    digitalWrite(this->pinTrigger, HIGH);
+    delayMicroseconds(10);
+    digitalWrite(this->pinTrigger, LOW);
+
+    return pulseIn(this->pinEcho, HIGH) / 1000.0;
+  }
+
+  double getMetres()
+  {
+    return this->getMilliseconds() * this->soundMetresPerMillisecond * 0.5;
+  }
+
+  double getCentimeters()
+  {
+    return this->getMetres() * 100;
+  }
+};
+
+class Clock
+{
+  int intervalPerSecond;
+  int timeStart = millis();
+  
+  public:
+  Clock(int intervalPerSecond)
+  {
+    this->intervalPerSecond = intervalPerSecond;
+  }
+
+  void reset()
+  {
+    this->timeStart = millis();
+  }
+
+  void wait()
+  {
+    int wait = 1000 / this->intervalPerSecond - (millis() - this->timeStart);
+    wait = wait > 0 ? wait : 0;
+    
+    delay(wait);
+  }
+};
+
+class Measurement
+{
+  double tolerance = 0.0;
+  double average = 0.0;
+  
+  public:
+  Measurement(HCSR04 sensor, int passes = 10)
+  {
+    double nearest = 99999.0;
+    double furthest = 0.0;
+    double distancesSum = 0.0;
+  
+    for (int i = 0; i < passes; ++i) {
+      double measurement = sensor.getCentimeters();
+
+      distancesSum += measurement;
+  
+      if (measurement > furthest) {
+        furthest = measurement;
+      }
+  
+      if (measurement < nearest) {
+        nearest = measurement;
+      }
+    }
+  
+    this->tolerance = (furthest - nearest) * 1.3;
+    this->average = distancesSum / passes;
+  }
+
+  double getTolerance()
+  {
+    return this->tolerance;
+  }
+
+  double getAverage()
+  {
+    return this->average;
+  }
+};
+
+const int PIN_OUTPUT = 3;
+
+HCSR04 sensor(2, 14);
+Clock measureClock(4);
+double distanceWall;
+double lastDist;
+double tolerance = 20.0;
+double toleranceWall = 20.0;
+bool active = true;
+int intervalPerSecond = 4;
+
+void scan(double dist) {
+  if (dist < 0) {
+    return;
+  }
+  
+  if (active) {
+    double difference = dist - lastDist;
+
+    if (difference > tolerance || difference < -tolerance) {
+      lastDist = dist;
+      digitalWrite(PIN_OUTPUT, HIGH);
+      delay(1000);
+      digitalWrite(PIN_OUTPUT, LOW);
+      active = false;
+    }
+  } else {
+    double difference = dist - distanceWall;
+
+    if (difference <= toleranceWall && difference >= -toleranceWall) {
+      active = true;
+      digitalWrite(PIN_OUTPUT, LOW);
+    }
+  }
+}
+
+void setup() {
+  pinMode(PIN_OUTPUT, OUTPUT);
+  digitalWrite(PIN_OUTPUT, LOW);
+
+  delay(3000);
+
+  Measurement measurement(sensor);
+
+  tolerance = measurement.getTolerance();
+  toleranceWall = measurement.getTolerance();
+
+  distanceWall = measurement.getAverage();
+  lastDist = distanceWall;
+}
+
+void loop() {
+  measureClock.reset();
+  
+  double dist = sensor.getCentimeters();
+
+  scan(dist);
+
+  lastDist = dist;
+
+  measureClock.wait();
+}