Ultrasonic scanning built on a tiny microcontroller, it sounds improbable, but Arduino makes it real. By pairing an ultrasonic sensor with a servo motor, makers and engineers can assemble a surprisingly capable object-detection system that scans surroundings and maps nearby objects in real time. As the sensor sweeps across its arc, it pulses sound waves that bounce back from whatever stands in their path, translating raw echo data into a live radar-style display on screen. Distance measured, env