circuits 3 & 4

Servo Motor :

// Sweep
// by BARRAGAN <http://barraganstudio.com>
// This example code is in the public domain.


#include <Servo.h>
 
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()
{
  myservo.attach(9);  // attaches the servo on pin 9 to the servo object
}
 
 
void loop()
{
  for(pos = 0; pos < 180; pos += 1)  // goes from 0 degrees to 180 degrees
  {                                  // in steps of 1 degree
    myservo.write(pos);              // tell servo to go to position in variable 'pos'
    delay(15);                       // waits 15ms for the servo to reach the position
  }
  for(pos = 180; pos>=1; pos-=1)     // goes from 180 degrees to 0 degrees
  {                                
    myservo.write(pos);              // tell servo to go to position in variable 'pos'
    delay(15);                       // waits 15ms for the servo to reach the position
  }
}

DC Motor:

/*     -----------------------------------------------------------
 *     |  Arduino Experimentation Kit Example Code               |
 *     |  CIRC-03 .: Spin Motor Spin :. (Transistor and Motor)   |
 *     -----------------------------------------------------------
 * 
 * The Arduinos pins are great for driving LEDs however if you hook 
 * up something that requires more power you will quickly break them.
 * To control bigger items we need the help of a transistor. 
 * Here we will use a transistor to control a small toy motor
 * 
 * http://tinyurl.com/d4wht7
 *
 */
 
int motorPin = 9;  // define the pin the motor is connected to
                   // (if you use pin 9,10,11 or 3you can also control speed)
 
/*
 * setup() - this function runs once when you turn your Arduino on
 * We set the motors pin to be an output (turning the pin high (+5v) or low (ground) (-))
 * rather than an input (checking whether a pin is high or low)
 */
void setup()
{
 pinMode(motorPin, OUTPUT); 
}
 
 
/*
 * loop() - this function will start after setup finishes and then repeat
 * we call a function called motorOnThenOff()
 */
 
void loop()                     // run over and over again
{
 motorOnThenOff();
 //motorOnThenOffWithSpeed();
 //motorAcceleration();
}
 
/*
 * motorOnThenOff() - turns motor on then off 
 * (notice this code is identical to the code we used for
 * the blinking LED)
 */
void motorOnThenOff(){
  int onTime = 2500;  //the number of milliseconds for the motor to turn on for
  int offTime = 1000; //the number of milliseconds for the motor to turn off for
 
  digitalWrite(motorPin, HIGH); // turns the motor On
  delay(onTime);                // waits for onTime milliseconds
  digitalWrite(motorPin, LOW);  // turns the motor Off
  delay(offTime);               // waits for offTime milliseconds
}
 
/*
 * motorOnThenOffWithSpeed() - turns motor on then off but uses speed values as well 
 * (notice this code is identical to the code we used for
 * the blinking LED)
 */
void motorOnThenOffWithSpeed(){
 
  int onSpeed = 200;  // a number between 0 (stopped) and 255 (full speed) 
  int onTime = 2500;  //the number of milliseconds for the motor to turn on for
 
  int offSpeed = 50;  // a number between 0 (stopped) and 255 (full speed) 
  int offTime = 1000; //the number of milliseconds for the motor to turn off for
 
  analogWrite(motorPin, onSpeed);   // turns the motor On
  delay(onTime);                    // waits for onTime milliseconds
  analogWrite(motorPin, offSpeed);  // turns the motor Off
  delay(offTime);                   // waits for offTime milliseconds
}
 
/*
 * motorAcceleration() - accelerates the motor to full speed then
 * back down to zero
*/
void motorAcceleration(){
  int delayTime = 50; //milliseconds between each speed step
 
  //Accelerates the motor
  for(int i = 0; i < 256; i++){ //goes through each speed from 0 to 255     analogWrite(motorPin, i);   //sets the new speed     delay(delayTime);           // waits for delayTime milliseconds   }      //Decelerates the motor   for(int i = 255; i >= 0; i--){ //goes through each speed from 255 to 0
    analogWrite(motorPin, i);   //sets the new speed
    delay(delayTime);           // waits for delayTime milliseconds
  }
}