This is the Arduino code needed to allow the Processing sketch to move the robot arm

arduino_robotarm

// by David Cummings 8/30/2012

#include <Servo.h> 
 
Servo Elbow;  // create servo object to control a servo 
Servo Shoulder;

int e_pos = 90;    // variable to store the servo position 
int s_pos = 90;
char read_char;
 
void setup() 
{ 
  Serial.begin(9600);
  Elbow.attach(3);  // attaches the servo on pin indicated to the servo object 
  Shoulder.attach(5);
  Shoulder.write(90); // some default start-up values, make these match your robot's settings
  Elbow.write(30);
} 

void loop() 
{ 
     if(Serial.available()>1){
       read_char = Serial.read();
       if(read_char == 's'){
        s_pos = Serial.read();
       }
       else if(read_char == 'e'){
        e_pos = Serial.read();
       }
       else{
        }
     }
    Shoulder.write(s_pos);
    Elbow.write(e_pos);   
}