Published April 19, 2019

Temperature Controlled Fan

This project is meant to give users the ability to have temperature dependent fan speed while working out.

BeginnerWork in progress796

Things used in this project

Hardware components

Particle Photon

DHT11 Temperature & Humidity Sensor (3 pins)

Stepper Motor, Mini Step

Breadboard (generic)

Jumper wires (generic)

Software apps and online services

Particle Build Web IDE

ThingSpeak API

IFTTT Maker service

Story

Background

When endurance athletes train indoors on a machine, such as a treadmill or a stationary bike, they never achieve the same level of cooling as they would if they were training outside. This is because while running or cycling outdoors, air passes over their body and cools them down. While indoors and training stationary, this same cooling effect doesn't take place unless a fan is introduced.

An example of a stationary bicycle with a fan placed in front of it.

The issue this project is meant to cover is controlling fan speed for athletes without forcing them to pause their workout to go and manually adjust it themselves. This is because when someone is working out at an easy to moderate intensity, they likely won't want the fan to be set to maximum speed. However, when they begin to increase intensity and duration, they will likely want more fan speed for more cooling. Also, when they begin to end their workout and go into a cool down mode, they will again want to change fan speed by reducing it.

How it works

The project would work by setting up a 2-way photon system to allow for controlling the fan in one location while monitoring the ambient temperature near the person working out. Since it's not feasible to measure an athletes core temperature on a continuous basis of multi-day use (do to the nature of measuring core temperature), this is the best option. It's expected that the temperature would rise anywhere from 2 to 5 degrees (sometimes more for smaller rooms and hard workouts) in a typical room space within a house after working out for approximately 15 to 30 minutes. This temperature gradient would be the basis for controlling the fan speed.

What worked

Several attempts were made to program the separate photons to communicate and act according to the logic stated earlier. Unfortunately, we were unable to solve some issues and get the project up and running fully.

The parts of equipment with both photons that was meant to run this project

We ended up trouble shooting sending temperature data through a web hook and found we weren't getting proper temperature readings which lead us to believe our temperature sensor was bad. Our plan was to use this webhook anyway, to gather data on how much heat is generated in my own room while conducting workouts.

Webhook with ThingSpeak

What we did get to work, is a simple servo motor. I will provide the code and a video of it running. The Photon was programmed with a tap button through IFTTT. In this format, if it was just one photon with control of a servo motor hooked up to a fan, it would enable remote control of the fan. This idea was thought of early in the development of this project but would leave out the 2-way communication criteria of the project, thus, it was not the nature of the project.

The point of the simple servo motor control, via an IFTTT button, was just to reiterate some lessons on how to communicate the Particle Photon with other programs to complete simple tasks.

Simple servo motor control through Particle and IFTTT

Code

#include <Adafruit_DHT.h>

#define DHTPIN 2
#define DHTTYPE DHT11

DHT dht(DHTPIN, DHTTYPE);

unsigned long last_time=0;
int how_often = 10000; //Take reading every 10 seconds
bool Celcius_or_Farenheit = true; //false for C, true for F

void setup() {
dht.begin();
}

void loop() {
if(millis()-last_time>how_often){
    String data = take_reading(Celcius_or_Farenheit);
    Particle.publish("tsenscrm", data);
    last_time = millis();
}
}

String take_reading(bool CorF){ //false for C, true for F
float t;
if(CorF){
    t = dht.getTempFarenheit();
}
else{
    float t = dht.getTempCelcius();
}
    return String(t);
}

Servo myservo;  // create servo object to control a servo
                // a maximum of eight servo objects can be created

int pos = 0;    // variable to store the servo position

void setup()
{
    Particle.function("gong", gong);  // create a function called "gong" that
                                      // can be called from the cloud
                                      // connect it to the gong function below

    myservo.attach(D0);   // attach the servo on the D0 pin to the servo object
    myservo.write(0);    // test the servo by moving it to 25°
    pinMode(D7, OUTPUT);  // set D7 as an output so we can flash the onboard LED
}

int gong(String command)   // when "gong" is called from the cloud, it will
{                          // be accompanied by a string.
    if(command == "now")   // if the string is "now", ring the gong once.
    {                            
        myservo.write(270);       // move servo to 0° - ding!
        digitalWrite(D7, HIGH); // flash the LED (as an indicator)
        delay(1000);             // wait 100 ms
       //myservo.write(3060);      // move servo to 25°
       digitalWrite(D7, LOW);  // turn off LED
        return 1;               // return a status of "1"
    }
    //else if(command == "alarm")     // if the string is "alarm",
    {                               
        //for (int i = 0; i < 3; i++) // ring the gong 3 times.
        {
           // myservo.write(0);       // move servo to 0° - ding!
            //digitalWrite(D7, HIGH); // flash the LED
            //delay(100);             // wait 100 ms
            //myservo.write(0);      // move servo to 25°
            //digitalWrite(D7, LOW);  // turn off LED
            //delay(1000);            // wait 1 second between gongs
        }
        //return 2;                   // return a status of "2"
    }
}

void loop()
{
  // empty because we call the gong function via the cloud
}

Credits

Carson McClelland

1 project • 0 followers

Peter Ensor

1 project • 0 followers

Thanks to Arduino “having11” Guy and Particle.

Temperature Controlled Fan