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.
Gastrobotics could allow users to deploy self-sustaining robots for extended times without human supervision. Common robots of today—powered by solar panels, batteries, or other energy sources—tend to become unreliable without human supervision for battery replacement, etc. Other robots must plug in to recharge, so they require constant access to an electrical outlet, which limits range. Solar powered robots are more independent but need a large surface area of solar panels to be efficient. This adds bulk and depends on weather conditions and clean panels to remain efficient. Gastrobotics might be able to live entirely off available natural resources. The main goal of this new technology is to produce robots that can go on missions where human supervision is not feasible or desirable.[1]
Some examples include
Gastrobotics energy sources mainly focuses on the use of a microbial fuel cell. Microbial fuel cells require an oxidation reduction reaction to generate electricity. A microbial fuel cell uses bacteria, which must be fed. The fuel cell typically contains two compartments, the anode and cathode terminals which are separated by an ion-exchange membrane.
First, in the anode chamber, the bacteria remove electrons from the organic material and pass the electrons to a carbon electrode. The electrons then move through the ion-exchange membrane to the cathode chamber, where they combine with protons and oxygen to form water. The electrons flowing from the anode into the cathode terminals generate electrical current and voltage. From this point, research is exploring using a hydrogen fuel cell to amplify the energy from the microbial fuel cell. The hydrogen fuel cell would use microbial fuel cell byproducts to create more energy without having to consume more material. Gastrobot requirements include:
The best fuel source for a gastrobot is anything high in carbohydrates. Vegetables, fruit, grains, insects, and foliage are good candidates. However, it can also consume organic waste products such as urine, anaerobic sludge (biodegradable waste and sewage), and landfill leachate. Meat can be a fuel, but contains too much fat to be efficient.[3]
The future of gastrobotics has many potential benefits to society.
The gastrobot is in its early development stages, and so faces many challenges:
As robots become more independent they must be more compliant. If a robot is out on a "mission" it must be sensitive to others around it instead of having a "complete task at all costs" mentality.[4]