Loading...
In-situ utilization of a specialized penetrometer on extraterrestrial bodies
Thrift, Ben C.
Thrift, Ben C.
Citations
Altmetric:
Advisor
Editor
Date
Date Issued
2024
Date Submitted
Collections
Research Projects
Organizational Units
Journal Issue
Embargo Expires
Abstract
As humanity returns to the Moon and prepares to venture beyond to other extraterrestrial bodies, methods for quickly evaluating in-situ surfaces will be necessary. The research in this thesis shows that individual tests with the specialized penetrometer can be analyzed to provide information about the character of a target sample. In-situ experiments, like those to be conducted with the SAMPLR payload, will enable future specialized penetrometer missions and operations on the Moon and will lay the groundwork for operations on other extraterrestrial bodies.
Analysis of samples with purposely altered properties was conducted to examine the response of a specialized penetrometer to differences in a target sample. Relative differences in the density, compressibility, particle size distribution, static friction properties of a target, stratification, and changes in these properties along the penetration path are apparent in the response of the instrument.
Design and operational requirements for a specialized penetrometer instrument mounted on a robotic arm were developed and implemented in the design of the SAMPLR payload. Design requirements related to the effective stiffness at tip, probe geometry, ultimate force, motion capabilities, sample rate, and signal to noise ratio informed the design. Operational requirements aided in the development of operational concepts and methodologies. Suggestions for specialized penetrometer operations were put forth with additional focus on how a specialized penetrometer can enable synergistic operations with other co-manifested instruments.
Methods were put forth on how to generate references in-situ to aid in the characterization of surfaces. In-situ calibration of a specialized penetrometer can be achieved by using a scoop and imagery to generate and evaluate test surfaces as references for calibration. The presented research provides methods and data to enable first approximations of in-situ surface characterization with a specialized penetrometer. \A\ parameter models were shown to be able to provide estimates of the relative density of unknown surfaces when generated using sufficient reference data. Methods of producing reference surfaces were proffered including generating reference piles for low relative density points and excavating to higher density subsurfaces to provide high relative density reference points.
Associated Publications
Rights
Copyright of the original work is retained by the author.