Everyone is familiar with pinwheels, and few of us haven’t crafted one from a square of paper, a stick, and a pin. Pinwheels are pretty optimized from a design standpoint, and are so cheap and easy to ...

Once you have a track and a kart to race on it, what’s missing? A lap counter that can give your lap times in hardcopy, obviously! That’s what led [the_anykey] to create the Arduino-based Lap Timer to ...

Electronic enthusiasts may be interested in a new open source infrared sensor which has been created to support both Raspberry Pi and Arduino powered projects. The IR Detector proximity sensor has ...

Figure 1a shows a slotted optical switch. An LED is mounted in a plastic housing, facing a phototransistor, but separated by a gap. If something moves into the gap, it blocks the light path between ...

What's behind the target can make a tremendous difference in how well reflective sensors do their job. Consider a photoelectric sensor operating in simple diffused mode (i.e., as a proximity sensor).