PJRC forum member VoiceBotX has created VoiceBot, a second language fluency-builder in the form of a Teensy 4.1-powered robot.

Contained in the 3d-printed shell is a Teensy 4.1 and Audio Adaptor Board, as well as haptic motors and drivers, some extra RAM, and an 8×8 RGB LED matrix. Using Teensy’s Ethernet, or USB serial via Chrome, the bot transmits a stream of visemes (speech sounds) to a web site, while also displaying them on the matrix, resulting in a lipsync-like representation of speech audio.