# 'Time to Get Out of Your Chair' Alarm

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## Introduction: 'Time to Get Out of Your Chair' Alarm

This is a device that warns and sets off an alarm when you've been sitting on your chair for too long, reminding you to get off of your @\$\$ and get some exercise! It's the Pomodoro Clock of Chairs, one chair to rule them all!

Working as a software developer as a day job means I am almost always glued to a chair. Many older people suffer from back problems due to the nature of the job. I have created a mechanism that may circumvent this problem by detecting how long you've been sitting on a chair and sounding an alarm if you have been there for too long!

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* Photosensor

* 10kΩ Resistor

* Jumper Cables

* Arduino

Tools:

* Soldering Iron

## Step 2: Solder

Since I wanted to go breadboard-less we'd need to solder the resistor onto one of the pins of the photosensor (call this pin 1) since the photosensor will use a voltage divider to relay input signals to the Arduino.

## Step 3: Connections

Follow the table below for the connections between the I/Os and the

I/OI/O pinArduino Pin
Photosensor1A0
Photosensor2GND**
Buzzer*19
Buzzer*2GND**

* Order of pins do not matter for the buzzer

** The Arduino board has at least 3 GND pins

## Step 4: Code

`/**`
``` * 'Get out of your chair alarm!'
* By TechMartian
*```
```/cosntants for the pins where sensors are plugged into.
const int sensorPin = 0;
const int buzzPin = 9;```
```unsigned long minute1;
float time1;```
```//Set up some global variables for the light level an initial value.
int bright;  // initial value
```void setup()
{
// We'll set up the LED pin to be an output.
bright = 900;
//we will take a single reading from the light sensor and store it in the lightCal        //variable. This will give us a prelinary value to compare against in the loop
}```
```void loop()
{```
`  lightVal = analogRead(sensorPin); // read the current light levels`
```  //if lightVal is less than our initial reading withing a threshold then it is dark.
if(lightVal <  bright)
{
// reset the timer, person began to sit down
minute1 = minute();
}  else   // otherwise it's bright
{
hour1 = -1;
minute1 = -1;
}
unsigned long minute = minute();
if (abs(60 - minute + minute1 )>20){
// time to stand up
while (lightVal <  bright) {  // still sitting
tone (buzzPin, 1000, 100);
delay (100);
noTone(buzzPin);  }
}
```
`}`

## Step 5: Setup

Place the photosensor at the back of the char where you won't sit on it, but will be blocked off of the light when you sit down.

## Step 6: Enjoy!

Enjoy your lengthened and healthier lifestyle!

Live long and Prosper!

Participated in the
Makerspace Contest 2017

Participated in the
MacGyver Challenge

Participated in the
Fix It Contest

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## Discussions

Hi I tried to do this but it didn't work. I changed the code a tiny bit by making a pin a different pin which is small. I then went to verify it and the code didn't work. I go try to fix it and find a couple of mistakes. Here is my code.

// 'Get out of your chair alarm!'
// By TechMartian
//cosntants for the pins where sensors are plugged into.
const int sensorPin = 0;
const int buzzPin = 11;
const int LED1 = 8;
unsigned long minute1;
float time1;
//Set up some global variables for the light level an initial value.
int bright; // initial value
int minute9;
int hour1;
void setup()
{
// We'll set up the LED pin to be an output.
bright = 900;
//we will take a single reading from the light sensor and store it in the lightCal //variable. This will give us a prelinary value to compare against in the loop
}
void loop()
{
//if lightVal is less than our initial reading withing a threshold then it is dark.
if(lightVal < bright)
{
// reset the timer, person began to sit down
minute1 = minute9;
digitalWrite(LED1, HIGH);
} else // otherwise it's bright
{
hour1 = -1;
minute1 = -1;
digitalWrite(LED1, LOW);
}
unsigned long minute = minute9;
if (abs(60 - minute9 + minute1 )>20){
// time to stand up
while (lightVal < bright) { // still sitting
tone (buzzPin, 1000, 100);
delay (100);
noTone(buzzPin); }
}
}

The digitalWrite for LED1 was to check if it worked. It may even work and I don't know yet. I used a breadboard and I have my sensor connected to the 3.3V as told, I have the resistor and a wire coming out of the other side of the sensor, the wire goes to the A0 and the resistor to the GND. My buzzer is on the 11pin and GND.

I hope you don't mind helping me.