In Chapter 7, we used the infrared LEDs and receivers to detect whether an object is in the BOE Shield-Bot’s way without actually touching it. Wouldn’t it be nice to also get some distance information from the IR sensors? There is a way to accomplish some rough, close-range detection with the very same IR circuit from the previous chapter. It’s just enough information to allow the BOE Shield-Bot to follow a moving object without colliding into it.
Determining Distance with the IR LED/Receiver Circuit
This chapter uses the same IR LED/receiver circuits from the previous chapter.
You will also need:
(1) sheet of paper
- If the circuit from the last chapter is still built on your BOE Shield-Bot, make sure your IR LEDs are using the 2 kΩ resistors (Figure 7‑7 on page 230.)
- If you already disassembled the circuit from the previous chapter, repeat the steps in Chapter 7, Activity #1, starting on page 228. Also, make sure to use TestBothIrAndIndicators to verify that the system is working properly.
- Download Chapter 8 Arduino Code