heat machine or love-o-meter

So we had to make a love machine or something similar. I decided to take the traditional path and work on a love-o-meter using a temperature sensor. The sensor, connected to an analog input, gave me numbers that I couldn’t read, so I used arbitrary numbers after playing around and exposing it to several temperatures. Depending on the values received a different number of LEDs would turn on. The hotter the more LEDs turned on.

Here’s how it looked:

 

Afterwards I revisited the code and looked at this example from the Arduino.cc tutorials

const int sensorPin = A0;
const float baselineTemp = 20.0;
void setup() {
  Serial.begin(9600);
  for (int pinNumber = 2; pinNumber < 5; pinNumber++) {
    pinMode(pinNumber, OUTPUT);
    digitalWrite(pinNumber, LOW);
  }
}

void loop() {
  int sensorVal = analogRead(sensorPin);

  Serial.print("sensor Value: ");
  Serial.print(sensorVal);

  float voltage = (sensorVal / 1024.0) * 5.0;

  Serial.print(", Volts: ");
  Serial.print(voltage);

  Serial.print(", degrees C: ");
  float temperature = (voltage - .5) * 100;
  Serial.println(temperature);

  if (temperature < baselineTemp + 2) {
    digitalWrite(2, LOW);
    digitalWrite(3, LOW);
    digitalWrite(4, LOW);
  } 
  else if (temperature >= baselineTemp + 2 && temperature < baselineTemp + 4) {
    digitalWrite(2, HIGH);
    digitalWrite(3, LOW);
    digitalWrite(4, LOW);
 
  else if (temperature >= baselineTemp + 4 && temperature < baselineTemp + 6) {
    digitalWrite(2, HIGH);
    digitalWrite(3, HIGH);
    digitalWrite(4, LOW);
  else if (temperature >= baselineTemp + 6) {
    digitalWrite(2, HIGH);
    digitalWrite(3, HIGH);
    digitalWrite(4, HIGH);
  }
  delay(1);
}

I downloaded, it made sense and worked. No puppies cried, but only one light went on.