Gaining access to the subsurface of planetary bodies is troublesome for a number of reasons, but particularly due to the low gravity encountered resulting in a lower available weight of spacecraft. A lower weight-on-bit (WOB) often results in sub-optimal drilling, and without complex anchoring or thrusting systems a planetary lander can only impart as much force as it weighs. This work investigates the use of ultrasonic vibration in assisting penetration through granular material. Compared to non-ultrasonic penetration, required forces have been observed to reduce by over a factor of 12. Similarly, total consumed power can be reduced by 28%, depending on the substrate and ultrasonic amplitude used. Tests were also carried out in high-gravity situations, displaying a trend that suggests these benefits would strengthen in lower gravity regimes
