A NASA funded robotics project at Cornell aims to create a luminescent, soft-bodied, eel-like robot to explore Europa and potentially other moons in the outer solar system. One of the most remarkable things about the design is the power system which would feed off of magnetic fields, using them to gather the components it needs to power itself.
In the further reaches of the solar system, solar power becomes scarce. This is even more obviously true in a deep ocean buried beneath a layer of ice. According to the Cornell team, the ‘eel’ will use the magnetic field to generate hydrogen and oxygen and then combine them to propel itself.
When hydrogen and oxygen are combined they produce a powerful reaction, they are in fact “the signature fuel of the American space program” according to NASA. A simple experiment can be done at home, using a standard two litre bottle that demonstrates the kind of energy this produces.
The robotic eel design has been awarded a grant under the NASA Innovative Advanced Concepts (NIAC) program to try to advance the idea’s TRL or tech readiness level. The current state of the project is rated as TRL 1, it would need to reach TRL 9 before it could be included in a Europa mission. The current round of funding is expected to take the project to TRL 2.
“We propose a rover architecture for Europa and other planetary environments where soft robotics enables scientific investigation or human-precursor missions that cannot be accomplished with solar or nuclear power. This rover resembles a squid, with tentacle-like structures that serve both as electrodynamic tethers to harvest power from locally changing magnetic fields and as a means of bio-inspired propulsion. The electrical energy scavenged from the environment powers all rover subsystems, including one that electrolyzes H20. Electrolysis produces a mixture of H2 and O2 gas, which is stored internally in the body and limbs of this rover. Igniting this gas expands these internal chambers, causing shape change to propel the rover through fluid or perhaps along the surface of a planetary body,” reads the overview on the NIAC website.
The robot would use a tether to generate small amounts of electricity from the flux in the water created by Jupiter’s magnetic field. It would then use that electricity to separate water into hydrogen and oxygen which would be stored and recombined to generate thrust.
The skin of the ‘eel’ is expected to be not only flexible but electroluminescent which will allow the underwater rover to capture images of the marine environment around it.
NASA is planning a mission to Europa which could launch as early as 2022, but that’s not the only place in the solar system where an eel rover could be useful. Jupiter’s moon Ganymede is believed to have an ocean, as well as its own magnetic field, which would make the eel’s propulsion system even more effective.
Saturn’s moons Enceladus and Mimas are also thought to have subsurface oceans. Titan, another moon of Saturn is also thought to have large lakes on the surface. However these are probably composed of methane, which would require a different kind of propulsion.
Of course, the Earth also has a magnetic field and 95% of our oceans remain unexplored according to NOAA’s Office of Ocean Exploration and Research.
