Robot line followers come in all shapes, sizes, and speeds. From very simple devices, with just a few transistors, to microcomputer-controlled versions, the basic strategy is still the same—follow a marked line on a floor.

The Raspberry Pi, with its powerful operating system, might seem like overkill for the task at hand. However, you can learn a great deal from designing and developing applications(s) and hardware and working through potential limitations.

The majority of line-following robot designs use infrared (IR) sensors or light-dependent resistors (LDR)) to sense the reflectivity of tape when it is used as the line to follow. These sensors invariably require A/D (analog to digital) convertors or amplifiers and level detectors to sense the target tape. When using a small microcomputer to drive a robot, you may have the required A/D and level-sensing hardware built in, and it may be capable of capturing a thousand or so samples per second.

In the case...