Yup, that's a pretty terrifying title. And yes, that's exactly what this is.
Tell me that I could name this anything different. Biomedical Engineering at it's most amusingly accessible right here!
So, what's physics-y about this? Apart from, you know, everything in existence being physics. First of all: magnets. These things are "remote controlled" by magnets and magnetic fields. You know, those things that you can't see but you have to contort your hands to figure out which direction they go and all that. I swear if any of you ask "magnets, how do they work?" you'll be deported off my blog
Also, since physics is all about movement, I should point out that the method of propulsion of this spermbot (yess I get to use that in real speech/typing!) is ingenious. Rather than use something that would have trouble maneuvering within the human body or which would create waste products, they used human cells that can easily propel themselves throughout viscous fluids (gross yes but needed) and that would have no trouble with the immune system.
Altogether, another useful product of BME