Planetary Micro-Penetrator Concept Study with Biomimetric Drill and Sampler Design

Due to ultraviolet flux to the surface layers of most solar system bodies, future astrobiological research is increasingly seeking to conduct subsurface penetration, drilling and sampling to detect chemical signature of extant or extinct life. To seek a compact solution to this issue, we present a micro-penetrator concept (mass < 10 kg) that is suited for planetary deployment and in situ investigation of chemical and physical properties. To draw inspiration from nature, a biomimetic drill and sampler subsystem is designed as a penetrator instrument based on the working mechanism of a wood wasp ovipositor to sample beneath the sterile layer for biomarker detection. One of the major limitations of sampling in relatively low gravity environments (such as asteroids, Mars, etc) is the need for high axial force when using conventional drills. The ovipositor drill is proposed to address this limitation by applying a novel concept of reciprocating motion that requires no external force. It is lightweight (0.5 kg), driven at low power (3 W), and able to drill deep (1-2 m). Tests have shown that a reciprocating drill is feasible and has the potential of improving drill efficiency without receiving any external force. As part of the European space agency (ESA) project on bionics and space system design [1], this study provides a conceptual design of the micro-penetrator targeted for a near earth asteroid mission. With bionics-enabling technology, the overall penetration/drilling/sampling system provides a small, light and energy efficient solution to in situ astrobiological studies, which is crucial for space exploration. Such a micro-penetrator can be used for exploration of terrestrial-type planets or other small bodies of the solar system with a moderate level of modifications.