One of the hardest things to do in planetary exploration, but one of the most valuable, is to sample a planetary surface – gather planetary dirt – and then transfer that dirt to a science instrument or sample return capsule. Current ways to do that, such as robotic arms, are costly and complex with lots of moving parts. Wouldn’t it be nice to have other options as well that could be used depending on the situation?
PlanetVac (Planetary Vacuum), from Honeybee Robotics, is a new technique to sample planetary regolith (the upper surface materials that overlie bedrock). It has the potential to be comparatively low-cost and very reliable due in part to a lack of moving parts. It can be used on Mars, the Moon, or asteroids. It could facilitate a rapid and reliable way to either get samples into in situ instruments on the spacecraft, or into a sample return capsule.
PlanetVac uses pressurized gas to push regolith into a sample container (effectively acting like a planetary vacuum cleaner). Because of the low pressures on Mars, the Moon, and asteroids, the technique is extremely efficient because the efficiency is related to the ratio of the pressure of the gas you are using to the ambient pressure. Landers typically have high pressure Helium already on board, used to pressurize the fuel tanks, which could be used as the gas.
The Planetary Society is supporting the next crucial step with PlanetVac: taking it from theory and piece meal tests to a full up test in Honeybee’s 3.4 meter (11 foot) vacuum chamber. Honeybee Robotics is designing, constructing, and testing a full system PlanetVac prototype. If we can experimentally demonstrate the technique is effective, then it has the potential to move to higher levels of development and to become another arrow in the quiver of tools available to sample planetary surfaces.
See the updates below to learn more about PlanetVac and to learn about its current status.
PlanetVac project leader Kris Zacny of Honeybee Robotics reports on presenting results of the Planetary Society project PlanetVac that created a prototype planetary dirt sampling system and tested it under Martian pressures.
Our PlanetVac development partner, Honeybee Robotics is no stranger to planetary exploration. They built the rock abrasion tool (RAT) for the Mars Exploration Rovers, the scoop for the Phoenix lander, and the brush and portions of the sampling system for MSL Curiosity. Their expertise makes them world leaders in sample manipulation, on Mars in particular, and we think they’ve come up with a worthy idea in PlanetVac.
Honeybee’s initial tests, conducted on reduced gravity flights and in vacuum chambers, demonstrated amazing sampling efficiency. However, no one has performed an end-to-end test under analog conditions. That is what Honeybee, with The Planetary Society, plan to do, building a prototype of PlanetVac by constructing the base of a landing vehicle with a PlanetVac system. Then, the prototype will be tested in Honeybee's 3.5m vacuum chamber using drop testing under Mars atmospheric conditions and lunar/asteroid vacuum conditions.
PlanetVac’s end-to-end sample acquisition and transfer system could provide a new solution to one of the most difficult problems in planetary exploration: the sampling and transferring of a sample to an instrument.