Reflectance Sensor

/**

 * @file: Reflectance Sensor Example

 * @date: 4/5/2011

 *

 * @DESCRIPTION

 * analog read of values 

 *

 */

#define analogPin A0

int sensorValue =0; // variable to store

//--- Function: Setup ()

void setup()

{

    Serial.begin(9600);

}

//--- Function: Loop ()

void loop()

{

    // read the value from the sensor:

    sensorValue = analogRead(analogPin);

    Serial.println(sensorValue);

    delay(500);

}

/**

* @file: Reflectance Sensor Example

* @date: 4/5/2011

*

* @DESCRIPTION

* Analog vs. digital

*

*/

#define analogPin A0

int sensorValue =0; // variable to store

//--- Function: Setup ()

void setup()

{

    Serial.begin(9600);

    pinMode(2, INPUT);

}

//--- Function: Loop ()

void loop()

{

     // read the analog value from the sensor:

    sensorValue = analogRead(analogPin);

    Serial.print("analog: ");

    Serial.println(sensorValue);

    delay(100);

    // read the digital value from the sensor:

    sensorValue = digitalReadu(2);

    Serial.print("digital: ");

    Serial.println(sensorValue);

    delay(500);

}

// SAMUEL T. WHITTEMORE

// ROBOT CONTROL FOR 2.007

// If you use this code, please reference Sam!

// include additional headers

#include <Servo.h>

//global declarations

#define RIGHTMOTOR 9        //define a pin for servo

#define LEFTMOTOR 8         //define a pin for servo

#define LED 13              //define a pin for LED

#define PHOTOR 5            //define a pin for Photo resistor

Servo rightmotor;         // initialize  servo

Servo leftmotor;          // initialize  servo

#define leftIRpin A0

#define rightIRpin A1

#define midIRpin A2

#define leverIRpin A4

const int lineIRthreshold = 850;

const int leverIRthreshold = 100;

// played around with values that sets the servos to each position

// these values need to be set for each servo!!!

int neutral = 1500;

int forward = 2000;

int backward = 1000;

int moveforward = 2000;

int movebackward = 1000;

int forwardlow = 1700;

int backwardlow = 1300;

int forwardmid = 1850;

int backwardmid = 1150;

int turnforward = 1750;

int leftIRval =0;         // variable to store

int midIRval =0;          // variable to store

int rightIRval =0;        // variable to store

int leverIRval = 0;

//--- Function: Setup ()

void setup()

{

  Serial.begin(9600);                     // setup serial output

  pinMode(LED, OUTPUT);                   // setup LED

  pinMode (RIGHTMOTOR, OUTPUT);           // want servo pin to be an output

  rightmotor.attach(RIGHTMOTOR);          // attach pin to the servo

  rightmotor.writeMicroseconds(neutral);  // set servo to mid-point

  pinMode (LEFTMOTOR, OUTPUT);             // want servo pin to be n output

  leftmotor.attach(LEFTMOTOR);             // attach pin to the servo

  leftmotor.writeMicroseconds(neutral);   // set servo to mid-point

}

//--- Function: Loop ()

void loop()

{  

  while(analogRead(leverIRpin) < leverIRthreshold )

  {

    int movebackward = 1350;

    int moveforward = 1690;

    // left and right off line

    if ((analogRead(leftIRpin) < lineIRthreshold) &&

      (analogRead(rightIRpin) < lineIRthreshold) )

    {

      rightmotor.writeMicroseconds(moveforward);

      leftmotor.writeMicroseconds(moveforward);

    }

    // right on line

    else if ((analogRead(leftIRpin) < lineIRthreshold) &&

      (analogRead(rightIRpin) > lineIRthreshold ))

    {

      rightmotor.writeMicroseconds(movebackward);

      leftmotor.writeMicroseconds(turnforward);

    }

    // left on line

    else if ((analogRead(leftIRpin) > lineIRthreshold) &&

      (analogRead(rightIRpin) < lineIRthreshold) )

    {

      rightmotor.writeMicroseconds(turnforward);

      leftmotor.writeMicroseconds(movebackward);

    }

    else

    {

      rightmotor.writeMicroseconds(neutral);

      leftmotor.writeMicroseconds(neutral);

    }

  }

}

Error = target_pos – current_pos  //calculate error

P = Error * Kp             //error times proportional constant gives P

I = I + Error             //integral stores the accumulated error

I = I * Ki                 //calculates the integral value

D = Error – Previos_error //stores change in error to derivate

Correction = P + I + D