System study and design of a multi-probe mission for planetary in-situ analysis

Abstract

Planetology has gained an overall picture of most surfaces of solar system bodies through observation satellites and robotic landers. However a novel method for the exploration of extraterrestrial surfaces is needed to complete remote observations with a global network of in-situ measurements. Miniaturized surface penetrators are a promising concept to fill the gap between remote observations and in-situ measurements. This work investigates the feasibility of the deployment of a large number of geochemical measurement instruments, integrated into high-velocity penetrators. The objective was to develop a mission strategy and architecture for a multi-microprobe planetary exploration system. To determine the quantity of probes needed, a landing site decision support system was developed in ArcGIS. The system uses a method to calculate the uncertainty in geochemical datasets in order to identify locations with high measurement uncertainty. This methodology was applied on data of the lunar surface: The identification of ISRU elements in the lunar soil is one of the highest objectives in the future attempts to return to the Moon. Thirty-one locations on the Moon are identified that can be used to perform ground control checks of the abundance of these elements. The ultimate goal of such a mission would be to develop a model of the surface abundances of elements that span the overall lunar surface. Based on this quantity as base specification, a miniaturized high-velocity penetrator concept is developed. Different carrier structures were analyzed through empirical formula and hydrocode simulations in LS-DYNA. The goal of this investigation was to evaluate the ruggedness of the carrier shell, evaluate the penetration depth and its impact behavior. A soil model of the lunar soil had to be developed to perform the numerical analysis. The result of this work was a modified penetrator design which is better suited to geochemical surface analysis. Several works identify the sampling mechanism for soil analysis as weak element in the development of high-velocity penetrators. Different sampling strategies are reviewed and novel methods suggested. Based on a technological analysis a sampling system that works like a vibrating conveyor was designed further. The efficiency of the system is evaluated analytically. The work concludes with a design of a high-velocity penetrator for geochemical analysis that can be deployed in large numbers on the surface of extraterrestrial surfaces.