Even if you try to use the lastest technologies… you are late 
.
Here is the Raspberry Pi Zero.
It seems to be 40% faster than the Raspberry 1.
I think it fits in Poppy’s head 
yep but no network …
Interesting. It is very small and cheap. With an ethernet or wifi USB dongle, certainly to consider.
And with a micro adapter from micro UBS to USB, the Pi Zero is a very compact choice.
Two problems: I guess it’s not enougth powerful for visual recognition, signals treatment etc, and how do you plan to drive the motors? Only two micro USB ports, one for the power and the other for Wifi… you already need a hub for anything that couldn’t use GPIO 
And now there’s the W version :
https://www.raspberrypi.org/products/pi-zero-wireless/
1 Like