The space exploration community is steadily moving towards the establishment of a semi-permanent base on the Moon. Excavation of the lunar regolith will be a key aspect of acheiving this goal, both for the construction of base structures, and for the mining of oxygen-rich material for in situ resource utilization (ISRU).
Mining on the Moon is very different from Earth. The Moon has low gravity, so mining systems have to be heavier to exert the same force. It has fine dust that abrades surfaces and destroys mechanical components. It has no atmosphere, prohibiting any sort of wet lubrication. Honeybee Robotics has several technologies under development to address the challenges of Lunar ISRU:
- Percussive digger – The percussive digger uses vibration or hammer action to reduce required digging forces by a factor of 40. This in turn reduces the mass requirement of the lunar excavator. Because every kilogram of Lunar mission payload adds approximately $100k to mission cost, this technology offers billions of dollars in savings.
- Pneumatic mining and transfer – Pneumatic excavation is an emerging technology which uses gas to mine and transport regolith. Initial test results have shown that one gram of pressurized gas can loft almost 6000 grams of soil under lunar-like conditions (gravity and vacuum). The excavation gas can be carried in liquid form in a designated tank, generated on-site by burning residual propellant in the lander, or even generated as a byproduct of the ISRU reaction process. Because the pneumatic system has no moving parts it is ideally suited to the abrasive lunar environment.