 // number of degrees to shake servo on each side of center
 const int SHAKE_OFFSET_ANGLE = 25;
 
+// infra red motion detectors
+const int IR_LEFT = 3;
+const int IR_RIGHT = 5;
+
+// diagnostic LED
+const int LED_DIAG = 13;
+
 //
 // GLOBALS
 //

  Serial.println(behaviorMode);

  switch (behaviorMode) {
    case 0:
    case 1:
    case 2:
      currAngle = oscillateGently(currAngle, random(3, 6));
      break;

    case 3:
      currAngle = shakeServo(currAngle, random(2, 4));
      break;
  }

  // wait random seconds until next loop

#include <Math.h>
#include <Servo.h>

// multiply by degrees to get radians
//
const double RADIANS_PER_DEGREE = 0.0174532925;

const int LEFT_LIMIT = 80;
const int RIGHT_LIMIT = 140;

// milliseconds to wait between servo movement: when servo is gently oscillating
const int GENTLE_DELAY = 100;

// milliseconds to wait between servo movement: when servo is shaking back & forth
const int SHAKE_DELAY = 10;
