AME Seminar: Leonard Vance

Abstract: Regolith from rubble pile asteroids is material that is essentially unchanged since the formation of our solar system. Sample and return missions to these bodies enable chemical and radioisotope studies which provide evidence for the formation of the solar system as well as maps for future mining. The touch-down and sample techniques established by Hayabusa-2 and OSIRIS-REx accomplish this mission by physically touching down on the asteroid and collecting samples into a basket extended via a probe from the bottom of the spacecraft. This technique has been demonstrated to work, but contains a high cost in operational risk as well as the size and complexity of the collection mechanism itself.

This presentation explores an alternative sample and returns technique that exploits the recent discovery of regolith particle ejections from Bennu. Particles ejected are typically 1-10 cm in size and spend several hours in flight, suggesting the possibility that nano-spacecraft deployed from a notional mother-spacecraft could chase down, collect and return such particles with minimal sensor and delta-V capability. Key aspects of this mission, including navigation and guidance, are developed to reduce risk, while an overall mission concept is developed to establish plausibility. A sample gathering technique for collecting larger non-cooperative objects is discussed, as is a demonstration test-bed that incorporates a central gravity attractor into an air-bearing table. Finally, it is shown that the particle ejections themselves contribute to the distinctive ‘top shape’ that many rubble pile asteroids exhibit.

Bio:  Leonard Vance is a Ph.D. candidate in aerospace engineering at the University of Arizona and a retired Raytheon engineer of 33 years experience. His career spans the early years of ballistic missile defense, where he helped develop a miniaturized LEAP kill vehicle as its System Engineering Lead. He then worked as Systems Lead during the development of the AIM-9X new generation Sidewinder missile, and then as chief engineer and program manager on a variety of initiatives adapting tactical missile expertise into classified space applications. He is a veteran of 25 missile flight tests, has a master's of engineering from Harvey Mudd College, and is currently working to complete his Ph.D. in aerospace and mechanical engineering with a minor in planetary science.