Her build uses the ubiquitous HC-SR04 SONAR sensor and a servo. This is a great use for a servo since a standard servo motor without modifications only moves through part of a circle, and that’s ...

Last time I used an HC-SR04 with a Teensy, I just wired the TRIG and ECHO pins together and told the NewPing Arduino library to use the same pin for both functions. I’m not sure where I read ...