I was wandering around github, (instead of studying OpenCV like my robot Carl wants of me), and ran across an interesting picamera motion detect demo that uses the picamera and numpy without needing OpenCV - (by Dave Jones, a Raspberry Pi guru).
Of course, Carl didn’t want to just notice motion, he had to get talkative when someone comes into the room. Here is Carl’s talking version. It uses Carl’s speak.py module and espeak, but easily adapted for any talking GoPiGo3.
Carl is waiting impatiently for me to finish learning OpenCV to cure his inability to find his way home, and can’t resist talking to me while I’m studying.