Ardoino Experiment with Servo and Sonar

Arduino_servo_sonar

// Controlling a servo position using a potentiometer (variable resistor) 
// by Michal Rinott <http://people.interaction-ivrea.it/m.rinott> 

#include <Servo.h> 
 
Servo myservo;  // create servo object to control a servo 
 
int potpin = 0;  // analog pin used to connect the potentiometer
int val;    // variable to read the value from the analog pin 
 
// Ultrasonic Sensor
int ultrasonic_trig_pin = 51;
int ultrasonic_echo_pin = 50;

long duration, cm;

 /*
 * Get the distance from the ultrasonic sensor 
 * return in cm
 */

long get_distance() {
  // Send soundwave
  pinMode(ultrasonic_trig_pin, OUTPUT);
  digitalWrite(ultrasonic_trig_pin, LOW);
  delayMicroseconds(2);
  digitalWrite(ultrasonic_trig_pin, HIGH);
  delayMicroseconds(10);
  digitalWrite(ultrasonic_trig_pin, LOW);
  // Read it
  pinMode(ultrasonic_echo_pin, INPUT);
  duration = pulseIn(ultrasonic_echo_pin, HIGH);

  return duration / 29 / 2; // Return in cm's
}

void setup() 
{ 
  Serial.begin(9600); 
  myservo.attach(21);  // attaches the servo on pin 9 to the servo object 
} 
 
void loop() 
{ 
  //val = analogRead(potpin);            // reads the value of the potentiometer (value between 0 and 1023) 
  //val = map(val, 0, 1023, 0, 179);     // scale it to use it with the servo (value between 0 and 180) 
  for(int i = -50; i < 180; i++) {
    myservo.write(i);    // sets the servo position according to the scaled value 
    Serial.print(get_distance());
    Serial.print("cm");
    Serial.print("\n");
    delay(20); 
  }
                          // waits for the servo to get there 
}