And here are some other pictures showing our work!

Published April 17, 2018 © GPL3+

Shower Temperature Sensor

Using this setup, we will successfully measure shower temperature and alert the user that the shower is ready.

IntermediateFull instructions provided20 hours2,780

Things used in this project

Hardware components

Particle Photon

Resistor 221 ohm

Resistor 4.75k ohm

Maxim Integrated DS18B20 Programmable Resolution 1-Wire Digital Thermometer

4xAA battery holder

LED (generic)

Breadboard (generic)

Software apps and online services

Particle Pi

io.adafruit.com

Story

As busy engineering students, we know the importance of saving time. Especially in the morning, every extra minute is well worth it. That's why we have created a shower temperature system. Using this system, you can turn on your shower and go back to whatever you were doing. Rather than having to stick your hand into the shower, you can wait for the system to notify you that the shower is ready. In addition to helping save time, this system also helps you avoid uncomfortable showers. No one likes getting into the shower, only to realize that the shower is freezing cold or scolding hot. Imagine the possibilities available with this temperature sensing system. With a target temperature and an accurate error reading, many of the building blocks are in place to turn a normal shower into a shower that can set its own temperature. Overall, this project has been a great learning experience, and we hope you find it useful!

Here's a video that explains our project:

And here are some other pictures showing our work!

A graph of the data taken during the video:

The temperature sensor board:

The indicator board:

The temperature sensor attached to a shower head:

Code

float V = 1;
int led2 ;
void setup() {
  pinMode(D0, OUTPUT);
  pinMode(D1, OUTPUT);
  pinMode(D2, OUTPUT);
  Particle.subscribe("Light_1", Light, MY_DEVICES);
}
void Light(const char *event, String data) {
  led2=data.toInt();
  if(led2== 2){
    digitalWrite(D0, HIGH);
    digitalWrite(D1, LOW);
    digitalWrite(D2, LOW);}
    else if(led2== 3){
    digitalWrite(D1, HIGH);
    digitalWrite(D0, LOW);
    digitalWrite(D2, LOW);}
    else if(led2== 4){
    digitalWrite(D2, HIGH);
    digitalWrite(D0, LOW);
    digitalWrite(D1, LOW);}
    else{
    digitalWrite(D0, LOW);
    digitalWrite(D1, LOW);
    digitalWrite(D2, LOW);}
    String connect = String(V);
    Particle.publish("connect_1", connect, PRIVATE);
  
}

Temperature Sensor Code

C/C++

This code allows the temperature sensor unit to detect the temperature, determine if the water is too hot or cold, determine the connection of the system and publish the temperature to adafruit.io.

The Adafruit Live graph can be found at https://io.adafruit.com/drd09876/feeds/temp

Approximately half of the code came from Particle's "Community Libraries". Specifically, the "OneWire" and "Adafruit_MQTT" libraries. Additionally some of the code pertaining to Adafruit originated from "MEGR 3171: adafruit example.txt" found on the MEGR 3171 canvas page. Finally the code to interpret the data from the temperature sensor was acquired from the particle.io tutorial "Tutorial #4: Temperature Logger".

// This #include statement was automatically added by the Particle IDE.
#include <Adafruit_MQTT.h>
#include "Adafruit_MQTT/Adafruit_MQTT_SPARK.h"
#include <OneWire.h>
OneWire ds = OneWire(D4);
unsigned long lastUpdate = 0;
float lastTemp;
void setup() {
  Serial.begin(9600);
  pinMode(D3, OUTPUT);
  pinMode(D5, OUTPUT);
  digitalWrite(D3, LOW);
  digitalWrite(D5, HIGH);
  
}
#define AIO_SERVER      "io.adafruit.com" 
#define AIO_SERVERPORT  1883                   // use 8883 for SSL 
#define AIO_USERNAME    "drd09876"
#define AIO_KEY         "046fc1faa19340dfa922d67f068ec31c" 
TCPClient TheClient; 
Adafruit_MQTT_SPARK mqtt(&TheClient,AIO_SERVER,AIO_SERVERPORT,AIO_USERNAME,AIO_KEY); 
Adafruit_MQTT_Publish temperature = Adafruit_MQTT_Publish(&mqtt, AIO_USERNAME "/feeds/temperature"); 
void loop(void) {
  byte i;
  byte present = 0;
  byte type_s;
  byte data[12];
  byte addr[8];
  float celsius, fahrenheit;
  if ( !ds.search(addr)) {
    Serial.println("No more addresses.");
    Serial.println();
    ds.reset_search();
    delay(250);
    return;
  }
  Serial.print("ROM =");
  for( i = 0; i < 8; i++) {
    Serial.write(' ');
    Serial.print(addr[i], HEX);
  }
  if (OneWire::crc8(addr, 7) != addr[7]) {
      Serial.println("CRC is not valid!");
      return;
  }
  Serial.println();
  switch (addr[0]) {
    case 0x10:
      Serial.println("  Chip = DS1820/DS18S20");
      type_s = 1;
      break;
    case 0x28:
      Serial.println("  Chip = DS18B20");
      type_s = 0;
      break;
    case 0x22:
      Serial.println("  Chip = DS1822");
      type_s = 0;
      break;
    case 0x26:
      Serial.println("  Chip = DS2438");
      type_s = 2;
      break;
    default:
      Serial.println("Unknown device type.");
      return;
  }
  ds.reset();    
  ds.select(addr);    
  ds.write(0x44, 0);
  delay(1000);
  present = ds.reset();
  ds.select(addr);
  ds.write(0xB8,0);
  ds.write(0x00,0);   
  present = ds.reset();
  ds.select(addr);
  ds.write(0xBE,0);   
  if (type_s == 2) {
    ds.write(0x00,0);
  }
  Serial.print("  Data = ");
  Serial.print(present, HEX);
  Serial.print(" ");
  for ( i = 0; i < 9; i++) {          
    data[i] = ds.read();
    Serial.print(data[i], HEX);
    Serial.print(" ");
  }
  Serial.print(" CRC=");
  Serial.print(OneWire::crc8(data, 8), HEX);
  Serial.println();
  int16_t raw = (data[1] << 8) | data[0];
  if (type_s == 2) raw = (data[2] << 8) | data[1];
  byte cfg = (data[4] & 0x60);
  switch (type_s) {
    case 1:
      raw = raw << 3; 
      if (data[7] == 0x10) {
        raw = (raw & 0xFFF0) + 12 - data[6];
      }
      celsius = (float)raw * 0.0625;
      break;
    case 0:
      if (cfg == 0x00) raw = raw & ~7;  // 9 bit resolution, 93.75 ms
      if (cfg == 0x20) raw = raw & ~3; // 10 bit res, 187.5 ms
      if (cfg == 0x40) raw = raw & ~1; // 11 bit res, 375 ms
      // default is 12 bit resolution, 750 ms conversion time
      celsius = (float)raw * 0.0625;
      break;
    case 2:
      data[1] = (data[1] >> 3) & 0x1f;
      if (data[2] > 127) {
        celsius = (float)data[2] - ((float)data[1] * .03125);
      }else{
        celsius = (float)data[2] + ((float)data[1] * .03125);
      }
  }
  if((((celsius <= 0 && celsius > -1) && lastTemp > 5)) || celsius > 125) {
      celsius = lastTemp;
  }
  fahrenheit = celsius * 1.8 + 32.0;
  lastTemp = celsius;
  Serial.print("  Temperature = ");
  Serial.print(celsius);
  Serial.print(" Celsius, ");
  Serial.print(fahrenheit);
  Serial.println(" Fahrenheit");
  String temperature = String(fahrenheit); 
  Particle.publish("temperature", temperature, PRIVATE);
  delay(10000);
}

Credits

Kyle Tucker

1 project • 0 followers

Mechanical Engineering Student at the University of North Carolina at Charlotte.

Dylan Duplessis

0 projects • 0 followers

Shower Temperature Sensor