[Symmetry]

Robots in human spaces can be done and, more to the point, the company I'm working for is doing it[1]. And there's the Google car too. It does require spending more on sensors than a hobbyist will want to spend and in our case it requires the occasional remote intervention when, for instance, someone leaves a box in the robot's parking spot.

[1]http://www.vecna.com/on-demand-delivery

[Rhapso]

I'm definitely approaching this from a hobbyist's point of view. My experience is limited to FIRST and a thrust vectoring bi-copter that was deemed too likely to maim or kill to be used in public spaces.