From the country where hotels are operated by robots and androids serve as clerks at department stores comes the latest unmanned project: the robot cab.

Japan’s cabinet office, Kanagawa prefecture and Robot Taxi Inc. on Thursday said they will start experimenting with unmanned taxi service beginning in 2016. The service will be offered for approximately 50 people in Kanagawa prefecture, just south of Tokyo, with the auto-driving car carrying them from their homes to local grocery stores.

According...