Abstract
A method is described for pre-fracturing rock using two or more counter-propagating millimeter-wave or microwave beams aimed at the same target volume from opposite sides. Standing-wave interference and overlapping absorption produce interior thermal-stress concentrations that initiate cracks at much lower bulk energy density than vaporization-based drilling, while the symmetric geometry largely cancels the net momentum imparted to the rock face. The architecture is intended primarily for low-gravity surface drilling on the Moon, Mars, and asteroids — where reaction-force budgets are extremely limited — and as a pre-conditioning step for terrestrial mechanical drills. The disclosure covers the baseline two-beam geometry at 100 GHz, lower-frequency variants (10–30 GHz and below) that trade hotspot resolution for deeper penetration into thicker rock, and multi-beam variants (four- and six-beam symmetric arrangements) that increase center-of-target energy deposition and produce three-dimensional crack-nucleation patterns. A combined two-stage embodiment uses lower-frequency beams for bulk softening and high-frequency beams for crack finishing. The disclosure describes the geometry, the energy balance, the principal physical limits (penetration depth, mineral-loss variability, standing-wave hotspot scale, emitter aperture scaling), prior art, and a brief note on integration with the author’s earlier orbital power disclosure (HRD-PUB-2026-01, OICK). The author is not seeking patent protection and offers this disclosure to the community to establish prior art.
Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 License.
Recommended Citation
Harbison, Daniel Austin, "Bilateral Beam-Assisted Rock Fracturing for Low-Gravity and Terrestrial Drilling Operations", Technical Disclosure Commons, (May 17, 2026)
https://www.tdcommons.org/dpubs_series/10142