I found an article on the robot OTTO BOT recently.
It is under CC-BY-SA V? license and was derived from Zowi which was derived from Bob.
A friend of mine in New Zealand 3D printed the plastics in ABS (print files from github). He (and wife) were visiting relatives in Sydney over the holiday period. So yesterday we put the plastics, servos, speaker and Ultrasonic sensors together. While I have the Arduino Nano and Expansion boards, I have decided to go straight to using a Prop (in my case one of my P8XBlade2 boards). I plan on getting my grandsons interested and building more, including adding a rotating head and arms.
Here are a couple of pics of my assembled OTTO bot... (A pen is used for size reference)