This ultrasonic radar project is from [mircemk] who uses a small ultrasonic distance sensor attached to a rotating platform. A motor rotates it around a 180-degree field-of-view and an Arduino ...

This Arduino-based Pomodoro timer project also uses this 25-minute cycle. Once you push the button to start the timer, it will run for 25 minutes, display a count-up timer and a "Study time ...

Halloween is right around the corner and just about every Halloween project needs some kind of motion sensor. Historically, we’ve used IR and ultrasonic sensors but [Makers Mashup] decided to… ...