While the acrylic model was never fully kitted out with the internals, Robothingus once again gained from the past. MK-III was a true marvel.
We had moved from a carpet house to one with hardwood floors, so opted for to keep the 2-wheel drive option, and added nose & tail casters for lots of skittering fun for the kitties. Added 6-axis accelerometer and barometric/temp/alt sensors to the array.
With all of the other systems nicely integrated, the plan was to skin an appropriately sized stuffed animal and, well... faux-taxidermy plus robots equals fun? Under the skin would be a variety of sensors including my braided tendons from the MK-I. With the MP3 player and some fun sounds, the reactivity of cats interacting with RT would have been fun. Ended up moving (again) before completion.
I still have the corpse, err... chassis and innards, as well as a majority of the source code. Maybe someday when my underground maker-space no longer floods I'll be able to resurrect it.
If ever RT is upgraded to MK-IV, I'd maybe do the following:
Hemispherical brain layout where the left and right sides of RT would each have small 3v Arduino Pro feeding to the central Mega2650. Each of the hemispherical Pro models would be powered from the main power unit and would receive inputs from 'sensor clusters.'
Each sensor cluster would be some number and type of sensors plus an ATtiny (Arduino on a chip) and a tiny battery like you'd see in rechargable ear-pods.
Each cluster could also have photovoltaic system to charge the cluster batteries, and maybe even upstream to the rest of the 'brain' power system. The unit would need to actively charge for the main drive-power unit.