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Aaron Olson

Publications and source records attributed to Aaron Olson.

14 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2024

Electrodynamic Regolith Conveyor

NASA KSC’s Swamp Works Electrostatics and Surface Physics Laboratory (ESPL) is developing a 4-phase Electrodynamic Regolith Conveyor (ERC) that could convey regolith without the risk of rotating or vibratory actuation, which could jam or require regular maintenance due to the abrasive nature of Lunar regolith. A prototype conveyor has been developed for laboratory testing in a simulated Lunar gravity environment using a suborbital vehicle. The results of the project will be used for development of the 4-phase electrodynamic conveyors for Lunar ISRU, regolith surface sampling, and dust mitigation solutions.

Aaron Olson↗
NASA NTRS2022

High-Vacuum Triboelectric Charging of Space Materials

In the high-vacuum environment of space and the surface of the moon, static electricity on surfaces lacks the atmospheric dissipation mechanisms found on earth. As a result, the ubiquitous triboelectric charging mechanism can lead to high levels of charge on surfaces. This static charge can result in damage to sensitive devices, interfere with communications, and electrostatic levitation of lunar dust. At the NASA Electrostatics and Surface Physics Laboratory (ESPL), we use different apparatuses and techniques to tribo-charge materials in high-vacuum (10-5 torr), including a tribo-robot and a triboelectric regolith-material stage (TRMS). The tribo-robot is used to rub two materials together, and fieldmeters and electrometers can be used to determine how much charge is on the materials. The TRMS is used to drag different materials onto a bed of lunar simulant. This system is used to characterize how materials may interact with lunar dust using fieldmeters, electrometers, and laser scattering. Using these methods, we are building a database of how different space materials charge when contacting each other at high-vacuum, and how materials triboelectrically interact with the lunar surface.

Joseph Toth↗
NASA NTRSDate not supplied

Thermal Radiator EDS

Explore the source record for details and available documents.

Krystal Acosta↗
NASA NTRSDate not supplied

Design and Testing of a Prototype Electrodynamic Regolith Conveyor for Lunar ISRU

NASA’s Kennedy Space Center’s (KSC) Swamp Works Electrostatics and Surface Physics Laboratory (ESPL) is developing a 4-phase Electrodynamic Regolith Conveyor (ERC) that could convey regolith without the risk of rotating or vibratory actuation, which could jam or require regular maintenance due to the abrasive nature of lunar regolith. Another goal of electrodynamic conveying is the reduction of conveying power, which is important considering the limited capacity of early-stage lunar power systems. The current state of the art (SOA) for lunar regolith conveying is based on recent NASA system studies for oxygen production plants. These plant designs require conveying rates around 100 kg/hr, to produce 10 mT/yr of oxygen from the regolith. To accomplish this, conventional augers and vibratory spiral conveyors have been identified as the SOA or the leading candidates due to their extensive use in the terrestrial material handling industry. At NASA KSC, the use of dynamic electric fields, generated by alternating high voltage on electrodes, has been developed as a dust mitigation solution known as the Electrodynamic Dust Shield (EDS). The EDS is being developed for lenses, solar panels, radiators, fabric and seals and is scheduled for a technology demonstration mission on the Moon in 2023. ESPL researchers have shown the ability to move thin layers (a few mm) of dust with mW of power. In Academia, researchers have shown the ability to electrodynamically convey regolith up to 1 kg/hr with a 4-phase EDS. This paper will describe the design and testing of a prototype ERC that could scale to support transporting regolith at ISRU relevant flow rates.

Lunar↗
NASA NTRSDate not supplied

Monodisperse Single-Material Granular Tribocharging Modeling and Experimental Validation

Charge transfer between insulating grains has been a topic of interest for many years as this phenomenon is extremely important to many areas in industry. Of particular interest to NASA is the behavior of electrically insulative dust grains such as those found on the lunar surface. Whether poured from a scoop during sample collection activities, agitated inside a drum via mining robots, or fluidized by a gas plume, particle-particle interactions between similar granular materials will be widespread on the Moon. Designers hope to have a predictive model for how dust grains are charged, transported, and deposited on flight systems to better understand issues electrostatics may cause in future missions. While difference in work function is often seen as a driver for charge transfer between two materials, this is an incomplete representation for insulative particles. Other asymmetries in the system can also lead to charge being transferred: one such being the difference between static vs dynamic particles. Experiments performed under vacuum in the Electrostatics and Surface Physics Laboratory (ESPL) clearly show that particles having more contacts with other particles tend to charge positively and particles having fewer contacts tend to charge negatively, despite being made from the same material. During these experiments, monodisperse (population of single diameter) spherical particles were held in a reservoir which was then elevated at one end to slope into a Faraday cup used to measure bulk charge of the grains. Care was taken to limit the number of spheres bouncing out of the cup, to isolate the beads from the container itself so that only grain-to-grain interactions occurred, and to assure neutrality of the beads before the experiment began. A discrete element method (DEM) modeling package already incorporating many granular mechanics interactions was augmented to include the electrostatic behaviors seen in experiments. The model can reproduce the experimental results above by tracking the number of contacts between pairs of individual grains and applying a charge transfer condition related to this contact parameter. The experimental results as well as their incorporation into the improved modeling suite will be discussed. Future work includes adding additional asymmetries into the experiments/model such as polydisperse populations of spherical particles and irregularly shaped grains.

electrostatics↗
NASA NTRSDate not supplied

Electrodynamic Regolith Conveyor Sub-Orbital Flight Experiment

The Electrodynamic Regolith Conveyor (ERC) is a technology that is being developed for soil sampling, beneficiation, specialized conveying applications and dust mitigation. The ERC is an extension of the Electrodynamic Dust Shield (EDS). The EDS has been developed for lenses, solar panels, radiators, fabric, and other applications and is scheduled for a technology demonstration mission on the Moon in 2024. The objective of the ERC sub-orbital flight experiment is to perform testing to advance the TRL of the ERC technology by measuring the regolith transport flow rate, power consumption and range of particle trajectories at four different inclinations in a simulated lunar gravity environment. This testing supports discrete element modeling efforts by grounding the simulations with test data.

Electrodynamic↗