ALISTRATI, Greece (AP) — Persephone is a tour guide in Greece, but perhaps not the type people are used to. Billed as the world’s first robot tour guide inside a cave, Persephone has been welcoming ...

Take a video tour of homes from our Listing of the Day series in Newton, Massachusetts; New City, Chicago; Kiawah Island, South Carolina; Los Angeles; and London’s St. John’s Wood neighborhood.

NASA is no stranger to innovative robots, but the agency's new robotic cave explorer still manages to inspire a sense of awe. In cooperation with researchers at Stanford University, NASA is developing ...

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