[grecy]

> you have to give way to a car that is approaching or entering the roundabout on your right - which often is opposite you. How will a self-driving car cope with detecting a vehicle behind the concrete barrier of a roundabout?

How does a human driver detect a vehicle behind a concrete barrier?

Either humans can see it and the intersection makes sense, of humans (and machines) can't see it and the whole setup does not make any sense.