Penelope the pretty pink paper pig — and the teenagers she inspired to write — showed me how swiftly I could be brought into a patient’s inner world if only I asked a new type of question.

Crafted from dried pig intestines, the little origami robot is designed to hatch from inside a swallowed capsule and unfold like an accordion. Once inside the swallower’s stomach, ...

An international team of researchers have teamed up to make a tiny folding robot that can remove button batteries from the stomach.