the big problem with driverless cars is who is to blame in an accident, the person behind thd wheel?  the car manufacturer? the company who makes the sensors or computer?  they like to have someone to blame and in the uk insurance companies are very jittery about driverless vehicles.  mercedes benz have now said their systems in  driverless trucks they are testing will only be a driver aid and a driver will have to be behind the wheel to take over in an emergency.