Datasheet

Chapter 7 • Navigating with Infrared Headlights
234 • Robotics with the BOE Shield-Bot
tone(4, 3000, 1000); // Play tone for 1 second
delay(1000); // Delay to finish tone
servoLeft.attach(13); // Attach left signal to pin 13
servoRight.attach(12); // Attach right signal to pin 12
}
void loop() // Main loop auto-repeats
{
int irLeft = irDetect(9, 10, 38000); // Check for object on left
int irRight = irDetect(2, 3, 38000); // Check for object on right
if((irLeft == 0) && (irRight == 0)) // If both sides detect
{
backward(1000); // Back up 1 second
turnLeft(800); // Turn left about 120 degrees
}
else if(irLeft == 0) // If only left side detects
{
backward(1000); // Back up 1 second
turnRight(400); // Turn right about 60 degrees
}
else if(irRight == 0) // If only right side detects
{
backward(1000); // Back up 1 second
turnLeft(400); // Turn left about 60 degrees
}
else // Otherwise, no IR detected
{
forward(20); // Forward 1/50 of a second
}
}
int irDetect(int irLedPin, int irReceiverPin, long frequency)
{
tone(irLedPin, frequency, 8); // IRLED 38 kHz for at least 1 ms
delay(1); // Wait 1 ms
int ir = digitalRead(irReceiverPin); // IR receiver -> ir variable
delay(1); // Down time before recheck
return ir; // Return 1 no detect, 0 detect
}
void forward(int time) // Forward function
{
servoLeft.writeMicroseconds(1700); // Left wheel counterclockwise
servoRight.writeMicroseconds(1300); // Right wheel clockwise
delay(time); // Maneuver for time ms
}
void turnLeft(int time) // Left turn function
{
servoLeft.writeMicroseconds(1300); // Left wheel clockwise
servoRight.writeMicroseconds(1300); // Right wheel clockwise
delay(time); // Maneuver for time ms