## 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!

* 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!