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A robotic exploration mission that would enter a lunar pit to characterize the environment is described. A hopping mechanism for the robot's mobility is proposed. Various methods of hopping drawn from research literature are discussed in detail. The feasibilities of mechanical, electric, fluid, and combustive methods are analyzed. Computer simulations

A robotic exploration mission that would enter a lunar pit to characterize the environment is described. A hopping mechanism for the robot's mobility is proposed. Various methods of hopping drawn from research literature are discussed in detail. The feasibilities of mechanical, electric, fluid, and combustive methods are analyzed. Computer simulations show the mitigation of the risk of complex autonomous navigation systems. A mechanical hopping mechanism is designed to hop in Earth gravity and carry a payload half its mass. A physical experiment is completed and proves a need for further refinement of the prototype design. Future work is suggested to continue exploring hopping as a mobility method for the lunar robot.
ContributorsMcKinney, Tyler James (Author) / Thangavelautham, Jekan (Thesis director) / Robinson, Mark (Committee member) / Asphaug, Erik (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2015-05
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When rover mission planners are laying out the path for their rover, they use a combination of stereo images and statistical and geological data in order to plot a course for the vehicle to follow for its mission. However, there is a lack of detailed images of the lunar surface

When rover mission planners are laying out the path for their rover, they use a combination of stereo images and statistical and geological data in order to plot a course for the vehicle to follow for its mission. However, there is a lack of detailed images of the lunar surface that indicate the specific presence of hazards, such as craters, and the creation of such crater maps is time-consuming. There is also little known about how varying lighting conditions caused by the changing solar incidence angle affects perception as well. This paper addresses this issue by investigating how varying the incidence angle of the sun affects how well the human and AI can detect craters. It will also see how AI can accelerate the crater-mapping process, and how well it performs relative to a human annotating crater maps by hand. To accomplish this, several sets of images of the lunar surface were taken with varying incidence angles for the same spot and were annotated both by hand and by an AI. The results are observed, and then the AI performance was rated by calculating its resulting precision and recall, considering the human annotations as being the ground truth. It was found that there seems to be a maximum incidence angle for which detect rates are the highest, and that, at the moment, the AI’s detection of craters is poor, but it can be improved. With this, it can inform future and more expansive investigations into how lighting can affect the perception of hazards to rovers, as well as the role AI can play in creating these crater maps.

ContributorsHayashi, Brent Keopele (Author) / Das, Jnaneshwar (Thesis director) / Mahanti, Prasun (Committee member) / Anand, Harish (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description
The lunar poles have hydrated materials in their permanently shadowed regions (PSRs), also known as lunar cold traps. These cold traps exist because of the Moon’s slight tilt of 1.5, which consequently creates these PSRs. In these shadows, the temperature remains cold enough to prevent the sublimation of volatile materials

The lunar poles have hydrated materials in their permanently shadowed regions (PSRs), also known as lunar cold traps. These cold traps exist because of the Moon’s slight tilt of 1.5, which consequently creates these PSRs. In these shadows, the temperature remains cold enough to prevent the sublimation of volatile materials for timescales spanning that of geologic times [Hayne et. al 2015]. PSRs are significant because they create an environment where water ice can exist within the first meter of regolith at the lunar poles, where many cold traps are present. These volatile materials can be observed through a process called neutron spectroscopy. Neutron spectroscopy is a method of observing the neutron interactions caused by galactic and extragalactic cosmic ray proton collisions. Neutron interactions are more sensitive to hydrogen than other elements found in the regolith, and thus are a good indicator of hydrated materials. Using neutron spectroscopy, it is possible to detect the hydrogen in these cold traps up to a meter deep in the regolith, thus detecting the presence of hydrated materials, water, or ice.
For this study, we used the Monte Carlo Neutral Particle Transport Code (MCNP6) to create a homogenous sphere that represented the PSRs on Moon, and then modeled five differing water contents for the lunar regolith ranging from 0-20 percent weight. These percent weights were modeled after the estimates for Shackleton crater, data from Lunar Reconnaissance Orbiter (LRO) mission, and data from Lunar Orbiter Laser Altimeter (LOLA).
This study was created with the LunaH-Map mission as motivation, seeking to exhibit what neutron data might be observed. The LunaH-Map mission is an array of mini-Neutron Spectrometers that will orbit the Moon 8-20 km away from the lunar surface and map the spatial
distribution of hydrogen at the lunar poles. The plots generated show the relationship between neutron flux and energy from the surface of the Moon as well as from 10km away. This data provides insight into the benefits of collecting orbital data versus surface data, as well as illustrating what LunaH-Map might observe within a PSR.
ContributorsEttenborough, Ivy E (Author) / Hardgrove, Craig (Thesis director) / Wadhwa, Meenakshi (Committee member) / Czarnecki, Sean (Committee member) / School of Earth and Space Exploration (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2020-05