#include <Servo.h> // Include Servo library
// Create Servo object
Servo myservo ;

// Variables
// pins
int servopin = 10;
// timers
long timer = 0;
int offset = 10;
// servo angle
int angle = 0;
int targetangle = 180;

// Setup
void setup(){
  Serial.begin(9600);
  pinMode(servopin,OUTPUT);
  myservo.attach(servopin);
  myservo.write(angle);
}

// Das Loop
void loop() {
    // Check the timer
    if(timer + offset < millis()) {
      // if the timer has passed, do the swing
      doSwing();
      // reset the timer
      timer = millis();
  }
}

void doSwing() {
  if (angle == targetangle) { 
    targetangle = random(181); 
    offset = random(1, 50);
    Serial.println(angle);     
    Serial.println(targetangle);  
  }
  if (angle < targetangle)  { angle = angle + 1; }
  if (angle > targetangle)  { angle = angle - 1; }
  myservo.write(angle);
}