NASA's Martian rover Curiosity is five times larger than its predecessors — about the size of an SUV — says Wired UK's Mark Brown. The energy needed to power it comes from a radioisotope power system. But researchers at the US Naval Research Laboratory would like to develop rovers about the size of a bag of sugar, and as such, need a smaller way to power the machines, Brown says. Well, you can't get much smaller than a microbe. "Gregory Scott at NRL's Spacecraft Engineering Department has been awarded a NASA Innovative Advanced Concepts research grant to investigate the initial phase of tiny planetary robots that are powered by bacteria," Brown reports. "Micro-robotic explorers, powered by microbial fuel cells, could represent an efficient and reliable energy source on a planet without human intervention." Such a microbial fuel cell would use the bacteria's metabolic processes to harvest electrons, and then send those through a circuit to generate electricity. Some of the energy produced by the bacteria could be used to maintain the rover's electronics and controls, while the rest could go toward charging a battery or capacitor, Brown says. With a fully charged battery, the rover could be able to perform more complicated tasks. NRL's Scott plans to focus his research on anaerobic bacteria like Geobacter sulfurreducens, Brown says.
Microbial Robots in Outer Space!
Jan 06, 2012