Code:

// Controlling a servo position using a potentiometer (variable resistor) 
// by Michal Rinott  
// Adapted by Niek (Lyron) for 4 servo's
#include  
 
Servo fullbody;  // create servo object to control a servo 
Servo head;  // create servo object to control a servo 
Servo leftarm;  // create servo object to control a servo 
Servo rightarm;  // create servo object to control a servo 
 
int fullbodypot = 0;  // analog pin used to connect the full body potentiometer
int fullbodyval;    // variable to read the value from the analog pin 
int headpot = 1;  // analog pin used to connect the head potentiometer
int headval;    
int leftarmpot = 2;  // analog pin used to connect the left arm potentiometer
int leftarmval; 
int rightarmpot = 3;  // analog pin used to connect the right arm potentiometer
int rightarmval; 
 
void setup() 
{ 
  fullbody.attach(9);  // Fullbody-servo is attached to digital pin 9
  head.attach(8);
  leftarm.attach(7);
  rightarm.attach(6);
} 
 
void loop() 
{ 
  val = analogRead(fullbodypot);            // reads the value of the potentiometer (value between 0 and 1023) 
  val = map(fullbodyval, 0, 1023, 0, 179);     //0 and 1023 are the min and max values the arduino reads from the pot (play around with this) and 0 and 179 are servo min and max degrees
  fullbodyservo.write(fullbodyval);                  // sets the servo position according to the scaled value 
  
   // do the same for the other 3 servo's and pots
  val = analogRead(headpot);           
  val = map(headval, 0, 1023, 0, 179);
  headservo.write(headval);
  
  val = analogRead(leftarmpot); 
  val = map(leftarmval, 0, 1023, 0, 179);
  headservo.write(leftarmval);
  
    val = analogRead(rightarmpot); 
  val = map(rightarmval, 0, 1023, 0, 179);
  headservo.write(rightarmval);
  
  delay(15);                           // waits for the servo's to get there  (ms)
}