One intrepid scientist and three resolute engineers and roboticists from the Jet Propulsion Laboratory (JPL) braved the heat and stench of a fumarole near Ormat’s Mammoth Pacific Geothermal Power Plant on Thursday, Sept. 19 to conduct a probe test for the possible future study of fumaroles on other planets. The team was collecting data from the probe as the first stage in the development of a robotic sensing tool that could descend on its own into underground cavities and fumaroles.
Dr. Florian Schwandner, a NASA Postdoctoral Program (NPP) Senior Fellow at JPL specializing in volcano surveillance, explained the challenges of using a robotic tool to explore a fumarole. Fumaroles often have extreme temperatures, limited visibility because of steam, and emit a mixture of gases, including carbon dioxide, ammonia, hydrogen sulfide, and others, some of which are corrosive; “a problem for equipment,” he said.
The test probe, “MacGyvered” in two weeks by roboticist David Matten, according to roboticist Matt Frost, was equipped with an optical, thermal and pressure sensor. “We’ve built a probe with a few sensors to see how even the most simple instruments survive in such an environment,” Dr. Schwandner said. The team’s hope, although it might sound counterintuitive, is that the probe will sustain damage. “If it survives, we don’t learn much,” he explained. “But if it has damage, you can learn from that. It’s a little like a crash test for a car.”
The overall objective for designing a robotic sensing tool that can withstand extreme temperatures and corrosion would be to perform measurements and retrieve samples from underground, whether on our planet or on other planets and planetary bodies, Dr. Schwandner said. “In the future, we [NASA and JPL] might go to Venus or to Io, one of Jupiter’s moons,” he said. “These are planets and planetary bodies that are volcanically active, and if we want to explore them, we need first to build something on Earth.”
Such future missions to other planets and planetary bodies could use a robotic sensing tool to search for signs of life, Dr. Schwandner said. He offered the example of Mars, a planet that has a surface irradiated by sunlight and subject to extreme temperatures. Yet extensive water ice resides beneath that surface. “Conditions stabilize underground,” Dr. Schwandner said; “[Mars] may even have liquid water. In order to find that, we have to explore underground.”
Another potential application for the robotic sensing tool developed by the team could be in the study of volcanoes on our own planet. Measuring gases from vents, as well as studying active volcanoes on the ground, pose their own threats to the safety of human researchers. “If we can send in a sensing device, we can reduce the risk for humans,” Dr. Schwandner said.
According to Matt Frost, the team is currently conceiving a “soda-can sized” robot. He noted the value of coming out into the field to observe the conditions at the fumarole site, calling the trip “a reconnaissance visit, to see what kind of robot we need to design.” David Matten, who built the probe, recalled a recent trip to the fumaroles, also known as “mud pots,” on the Salton Sea. The wet, hot environment there provided a useful counterpoint to the drier, more temperate environment near Mammoth, he said. Considering these two extremes, “We have to ask ourselves if we want to have two robots, or one robot for every system,” he said.
Ormat Plant Manager John Bernardy thanked the team for their work, noting that the data they collet with their probe, and any future study made of the fumarole, “will help us out, too.”
Stuart Wilkinson of the U.S. Geological Survey (USGS), the team’s host, also saw potential future applications for the robotic sensing tool. The USGS primarily monitors seismology, ground deformation and gas emissions, he said. Such a tool “could offer great support in terms of accessing remote or difficult locations,” he said.
Dr. Schwandner called the meeting of agencies and organizations at the fumarole “a good interagency collaboration. This is a nice opportunity to bring everyone together,” he said.