/challenges-projects/project14/attackofthedrones/b/blog/posts/alpha-rover---ultrasonic-rangingTime to try the Ultrasonic distance sensor with the panning servo mount. The Ultrasonic detector uses the common HC-SR04 module. It emits a stream of eight 40 kHz pulses and provides an ECHO pulse whose width is proportional to the reflect...en-USTelligent Community 12