Gastrobot, meaning literally 'stomach robot', was a term coined in 1998 by the University of South Florida Institute's director, Dr. Stuart Wilkinson. A gastrobot is "...an intelligent machine (robot) that derives all its energy requirements from the digestion of real food." The gastrobot's energy intake may come in the form of carbohydrates, lipids etc., or may be a simpler source, such as alcohol.
The energy source commonly used for this robot is a mixture of carbohydrates and protein. The robot gets these molecules through a microbial fuel cell (MFC), which converts the food into gases and other potential energy. The gases and liquids help fuel things such as a hydrogen fuel cell, which helps create more energy—and other gases that help power the gastrobot's mechanics.
These robots might be able to perform certain types of so-called 'start and forget' missions, such as to help maintain a particular ecological environment by removing invasive species. They might use optic sensors inputs to artificial intelligence software to determine what they can eat for energy conversion.