[Guilherme Martins] rose to a challenge to build a robot with a single servo. His robot is a puppet controller, called talkie walkie. In real time, it will move its mouth to the sound of what you ...

Switching the magnets on and off, and moving the servos in time, allows the robot to pull itself along a ferromagnetic surface. The robot is outfitted with buzzers and LEDs, and using these ...