Automated Unit 3947 was an Automated Personnel Unit created by the Pralor and programmed as a ship's maintenance unit. He was activated by a Builder on the Pralor homeworld in the year 2222. In 2372, unit 3947 (who had, at that point, been in service roughly 150 years) was badly damaged and adrift in space after its asteroid mining pod was disabled. It was later discovered by B'Elanna Torres, who, with the assistance of The Doctor, Harry Kim, and Kathryn Janeway, was able to repair it.