11. November 2010

Here is the Arduino source code for the "Breathing Pillow". We used Arduino to be able to use the pillow without any connection to a computer.

#include <Servo.h>
 
Servo myservo;  // create servo object to control a servo
                // a maximum of eight servo objects can be created

int minSpeed = 20; // Minimal Speed   
int startValue = 180; // Start Value for the Servo
int delayValue = 15; // Start Value for th delay, this value will be changed during runtime depends on the speed
int sleepPos = 180; // current position of the servo max speed to make the sleep movement slower
int pos = 0;    // variable to store the servo position
int sleepChange = 1;
int delayChange = 1; 
int changeAfterRepeat = 3;
int repeat = 0;




void setup()
{
  Serial.begin(9600);
  myservo.attach(13);  // attaches the servo on pin 9 to the servo object
}
 
 

 
void loop()
{
 
    int sensorValue = analogRead(A0);
    int thisPitch = map(sensorValue, 0, 1024, minSpeed, 180);
    int dif = startValue-thisPitch;
    
    if(dif >= 20 || dif <= -20)
    {
      startValue = thisPitch;
      sleepPos = thisPitch;
      delayValue=  map(thisPitch, 0, 180, 60, 15);
    }
    
    for(pos = 0; pos < sleepPos; pos += 1)  
    {                                 
      myservo.write(pos);    
      
      if(pos == 0 && sleepPos >0)
      {
        if(repeat ==changeAfterRepeat)
        {
          sleepPos -= sleepChange;
          repeat = 0;
          delayValue += delayChange;
        }
        else
        {
          repeat ++;
        }
      }
 
      delay(delayValue);                       
  }
  
  for(pos = sleepPos; pos>=1; pos-=1)    
  {                                
    myservo.write(pos);             
    delay(delayValue);                    
  }
}