Some of you might have heard about Dominoes Robotic Unit (DRU) which was announced publicly a few weeks ago.
And while we can all applaud that humans are now one step closer to never leaving their couches. 
However, until that day robots are in grave danger. Just last year the poor defenseless Canadian HitchBot (http://www.hitchbot.me/) was destroyed near Philadelphia. This makes the design of DRU highly concerning. It lacks an apparent righting system. We all know that robot immobilization can negatively affect the fate of whole planets in addition to the operation in which the robot is currently engaged.
DRU’s defensive design is also questionable. There has been some mention of DRU recording the images of assailants. It’s not confirmed if even this minimal level of protection will be implemented. However I feel compelled to point out that this system will be insufficient in light of HitchBot’s dismembered while carrying no cargo. DRU primary function will be transportation of goods which will dramatically increase the likelihood of ‘freak angle grinder accidents.’ so DRU clearly needs and active defense system.
I’m just waiting for the big companies to start using autonomous robots on a regular basis so they can realize how terrible the idea is without some sort of protective measures. The vast majority of people may not harm them, but can you imagine that DRU on a college campus or the Bronx? It’d be like the dodo bird.
“Hello, I’m filled with tasty things and can’t fight back.”
The best chance the DRU would have (if it can’t pack heat) is to get an engine (e.g., one of Tesla’s) that can allow it to go from 0 to 60 in ~2.8 seconds. That way it can get away if it knows it’s being targeted. Though being able to just allow it to shoot the pizza at the house might work too. That allows for drive-by pizza-ing.
I will say this, though, as long as DRU stays away from Philly, it should be fine. Philly is a garbage city and everyone knows it. Not amount of active defense systems could protect a robot from the people (and I use the term loosely about citizens of Philly) who once angrily threw batteries at Santa. Though I will say, as a pizza delivery system myself, I like the idea of DRU meaning I don’t have to go outside and see nearly as many penises when I arrive at your house. Seriously, people, if you’re ordering food, put some frakking pants on when you answer your door, you savages! I don’t want to have to worry about seeing old man junk every time I knock on a door.