1. 1 Chapter 7: Navigating with Infrared Headlights Presentation based on: "Robotics with the Boe-Bot" By Andy Lindsay Parallax, Inc Presentation developed by: Martin A. Hebel Southern Illinois University Carbondale College of Applied Sciences and Arts Electronic Systems Technologies 7/6/04

2. 2 Infrared

3. 3 Infrared Headlights Close object will reflect the light back to the sensor.

4. 4 Parts and Assembly

5. 5 Circuit

6. 6 To use the sensor: FREQOUT to the LED at 38,500KHz Record the detector's output.

7. 7 Why 38,500? Infrared is abundant around us (emitted as part of heat from many objects – including us). But, objects do not emit it on and off at 38,500Hz. The detector will ignore any source of IR except at that frequency. RF systems and FM and AM radio work the same way – ignoring source and frequencies they don't care about.

8. 8 Object Detection and Avoidance "RoamingWithIR.bs2"

9. 9 To change the sensitivity, change the size of the LED resistor.