In all the CES coverage I found a link to the Sphero robot. The bot charges via induction, like a TouchStone or PowerMat, so there are no ports to get dirty.

Based on the video, it looks like a larger model could easily have a camera or other sensors mounted inside the clear-body model.

If one comes at me, calling itself Haro, I'm drop-kicking it into next week.....

Honestly, unless that thing is packed entirely full, a camera ought to be a piece of cake to install inside second generation models. IRL, it'll need some shock frills though, or someone can just pick it up and walk away with it once it gets out of range to be physically protected by you and your commands.

Remington sold something they called the "Eye Ball R1" in 2006. Seems to be discontinued now

But here is a web page for it. http://tacticaldepo.com/eyr1suba.html

Looks like the Remington is the immobile sensor ball in Arsenal since the specs have no movement rate, only a revolution speed for pan & tilt.

Shock-frills could be added without much problem. The spherobot already uses induction for charging, the same induction system could send power to the taser unit.