Giving your robots moving eyes is one way to make them more interactive. As the latest guide from Adafruit shows, you won’t have to break the bank to try such a project. You are going to need an Adafruit Crickit, Circuit Playground Express, servos, batteries, a ping pong ball, and paint to get started.
You can control the animatronic gaze with pre-programmed movements. More information is available here.