For hardware details, see COMPONENTS below.

Safety features:

- Doubled shaft collars

- Nylock nuts in stressed places

- Metal straps around pole ends in case holes crack (no cracks yet)

- Modified code so random flapping only if button pressed

- Modified flapping code for smoother parabolic motion

Arduino code:

// RoboRaptor by Claus Buchholz

#include <Servo.h> 
 
Servo lw, rw;  // left wing, right wing 
const int of = 40;    // offset to servo positions
const int le = 2, re = 3, r1 = 4, y1 = 5, r2 = 6, y2 = 7;  // 6 LEDs
const int vo = 8;  // voice
const int sw = 11;  // switch
int lr = LOW, ly = LOW, ct = 0;
 
void setup() 
{ 
  lw.attach(9, 700, 2300);  // VEX Servo motors - 1500 pulse width at center
  rw.attach(10, 700, 2300);
  pinMode(le, OUTPUT); digitalWrite(le, HIGH);
  pinMode(re, OUTPUT); digitalWrite(re, HIGH);
  pinMode(r1, OUTPUT); digitalWrite(r1, LOW);
  pinMode(y1, OUTPUT); digitalWrite(y1, LOW);
  pinMode(r2, OUTPUT); digitalWrite(r2, LOW);
  pinMode(y2, OUTPUT); digitalWrite(y2, LOW);
  pinMode(sw, INPUT_PULLUP);
  pinMode(13, OUTPUT); digitalWrite(13, LOW);
  lw.write(of+50);  // idle positions
  rw.write(180-of-50);
} 
 
void loop() 
{ 
  int bt = digitalRead(sw);
  if (bt==HIGH || (++ct>3 && random(100)<99)) {  // if switch not pressed,
    int ey = (random(100)<5) ? LOW : HIGH;  // blink eyes at random
    digitalWrite(le, ey);
    digitalWrite(re, ey);
    delay(100);
    if (bt==HIGH) ct = 0;
    return;
  }  // if switch pressed, flap wings and belch fire
  for (int i=48; i>=0; i-=2)
  {
    int p = i*i/50;
    lw.write(of+p);  // wings up
    rw.write(180-of-p);
    delay(20);
  } 
  digitalWrite(le, LOW);  // eyes off
  digitalWrite(re, LOW);
  for (int i=0; i<100; i++)
  {
    tone(vo, 3000-3*i, 18);  // screech
    int p = (i<50) ? i*i/50 : 100-(100-i)*(100-i)/50;
    lw.write(of+p);  // step wings down
    rw.write(180-of-p);
    if (i%5==0) {  // sequence red and yellow LEDs at random for fire
      digitalWrite(r2, lr);
      digitalWrite(y2, ly);
      lr = (random(100)<10) ? LOW : HIGH;
      ly = (random(100)<30) ? LOW : HIGH;
      digitalWrite(r1, lr);
      digitalWrite(y1, ly);
    }
    delay(20);
  } 
  lr = ly = LOW;
  digitalWrite(r1, lr);  // fire off
  digitalWrite(y1, ly);
  digitalWrite(le, HIGH);  // eyes on
  digitalWrite(re, HIGH);
  digitalWrite(13, HIGH);
  delay(100);
  digitalWrite(r2, lr);  // fire off
  digitalWrite(y2, ly);
  digitalWrite(13, LOW);
  for (int i=98; i>=50; i-=2)
  {
    int p = 100-(100-i)*(100-i)/50;
    lw.write(of+p);  // wings to glide
    rw.write(180-of-p);
    delay(20);
  } 
}