[Waterproof DS18B20 Sensor Kit tutorial_2] A BATHING CAT FOR YOUR BATHING

I have to admit that taking a bath can greatly help relax. And I prefer hot tubbing, no matter it’s summer or winter season. But that can be annoying when you can not estimate whether the temperature is proper. What's more, I bag most of us need a timer when you enjoy yourselves in the tub.So I decided to deal with such a BATHING COMPANION.The anime character is from RIPNDIP one of my favourite brands.
STEP 1 Design & Material Required

Material Required:
RGB LED module 5050

DFRduino Nano 3.0 

# LR44 cell battery(with a case) [for independent power supply]

USB Cable 

Waterproof DS18B20 Sensor Kit 

some PMMA, and some wire

We need two functions :
I. A timer(cos I used to stay in bathroom for too long)
II. A temperature sensor(cos I never wanna to do any move like this

Solution :
I. I made a timer by Arduino IDE and use LED to hint you about time.
II. I take Waterproof DS18B20 Sensor as a “cat tail” to show if the temperature is proper.

And we need a holder to hold all these stuff.And it should be as simple as possible.

Here is a draft of the holder :

STEP 2 circuit logic & code
 

Code: Select all#include <OneWire.h> #include <RGBLED.h> RGBLED myled = RGBLED(9,10,11); int DS18S20_Pin = 2; //DS18S20 Signal pin on digital 2 //Temperature chip i/o OneWire ds(DS18S20_Pin);  // on digital pin 2 int ledPin = 9;                // Connect LED on pin 9, or use the onboard one int KEY = 3;                 // Connect Touch sensor on Digital Pin 3 void setup(){  Serial.begin(9600);  pinMode(ledPin, OUTPUT);      // Set ledPin to output mode  pinMode(12, OUTPUT);  pinMode(KEY, INPUT);       //Set touch sensor pin to input mode } void loop(){  float temperature = getTemp();  Serial.println(temperature);    delay(100); //just here to slow down the output so it is easier to read   if(temperature >= 40) {      //Read Touch sensor signal        digitalWrite(12, LOW);        digitalWrite(ledPin, HIGH);   // if Touch sensor is HIGH, then turn on     }   else if(digitalRead(KEY)==HIGH){         //start the timer   delay(1800000);    digitalWrite(12, LOW);    digitalWrite(10, HIGH);    delay(60000);    }   else{        digitalWrite(ledPin, LOW);    // if Touch sensor is LOW, then turn off the led     } } float getTemp(){  //returns the temperature from one DS18S20 in DEG Celsius  byte data[12];  byte addr[8];  if ( !ds.search(addr)) {      //no more sensors on chain, reset search      ds.reset_search();      return -1000;  }  if ( OneWire::crc8( addr, 7) != addr[7]) {      Serial.println("CRC is not valid!");      return -1000;  }  if ( addr[0] != 0x10 && addr[0] != 0x28) {      Serial.print("Device is not recognized");      return -1000;  }  ds.reset();  ds.select(addr);  ds.write(0x44,1); // start conversion, with parasite power on at the end  byte present = ds.reset();  ds.select(addr);      ds.write(0xBE); // Read Scratchpad    for (int i = 0; i < 9; i++) { // we need 9 bytes    data[i] = ds.read();  }    ds.reset_search();    byte MSB = data[1];  byte LSB = data[0];  float tempRead = ((MSB << 8) | LSB); //using two's compliment  float TemperatureSum = tempRead / 16;    return TemperatureSum;   }

STEP 3 Structure

I wanted to make it as simple as possible, so I did some laser-cutting stuff.
And then screw on
STEP 4 assembling
Hint: adjust the screw to make sure the case can hold ‘the cat tail’
Check it yourself!!!