Investigating the Feasibility of Utilizing Carbon Nanotube Fibers for Spacesuit Dust Mitigation

Historical data from the Apollo missions has compelled NASA to identify dust mitigation of spacesuits and other components as a critical path prior to sending humans on potential future lunar exploration missions. Several studies thus far have proposed passive and active countermeasures to address this challenge. However, these technologies have been primarily developed and proven for rigid surfaces such as solar cells and thermal radiators. Integration of these technologies for spacesuit dust mitigation has remained an open challenge due to the complexity of suit design. Current research investigates novel methods to enhance integration of the Electrodynamic Dust Shield (EDS) concept for spacesuits. We leverage previously proven EDS concept developed by NASA for rigid surfaces and apply new techniques to integrate the technology into spacesuits to mitigate dust contamination. The study specifically examines the feasibility of utilizing Carbon Nanotube (CNT) yarns manufactured by Rice University as electrodes in spacesuit material. Proof of concept testing was conducted at NASA Kennedy Space Center using lunar regolith simulant to understand the feasibility of the proposed techniques for spacesuit application. Results from the experiments are detailed in this paper. Potential challenges of applying this technology for spacesuits are also identified

Neptune Polar Orbiter with Probes

The giant planets of the outer solar system divide into two distinct classes: the gas giants Jupiter and Saturn, which consist mainly of hydrogen and helium; and the ice giants Uranus and Neptune, which are believed to contain significant amounts of the heavier elements oxygen, nitrogen, and carbon and sulfur. Detailed comparisons of the internal structures and compositions of the gas giants with those of the ice giants will yield valuable insights into the processes that formed the solar system and, perhaps, other planetary systems. By 2012, Galileo, Cassini and possibly a Jupiter Orbiter mission with microwave radiometers, Juno, in the New Frontiers program, will have yielded significant information on the chemical and physical properties of Jupiter and Saturn. A Neptune Orbiter with Probes (NOP) mission would deliver the corresponding key data for an ice giant planet. Such a mission would ideally study the deep Neptune atmosphere to pressures approaching and possibly exceeding 1000 bars, as well as the rings, Triton, Nereid, and Neptune s other icy satellites. A potential source of power would be nuclear electric propulsion (NEP). Such an ambitious mission requires that a number of technical issues be investigated, however, including: (1) atmospheric entry probe thermal protection system (TPS) design, (2) probe structural design including seals, windows, penetrations and pressure vessel, (3) digital, RF subsystem, and overall communication link design for long term operation in the very extreme environment of Neptune's deep atmosphere, (4) trajectory design allowing probe release on a trajectory to impact Neptune while allowing the spacecraft to achieve a polar orbit of Neptune, (5) and finally the suite of science instruments enabled by the probe technology to explore the depths of the Neptune atmosphere. Another driving factor in the design of the Orbiter and Probes is the necessity to maintain a fully operational flight system during the lengthy transit time from launch through Neptune encounter, and throughout the mission. Following our response to the recent NASA Research Announcement (NRA) for Space Science Vision Missions for mission studies by NASA for implementation in the 2013 or later time frame, our team has been selected to explore the feasibility of such a Neptune mission

Engineering Considerations in Design of High Temperature Electronics for Planetary Probes

This presentation was part of the session : Extreme EnvironmentsSixth International Planetary Probe WorkshopLow weight and high reliability are primary goals in scientific exploration space missions. Many mission concepts involve probes operating at high ambient temperatures for various lengths of time. In these cases, high-temperature electronics can simplify the system design and reduce overall mass, resulting in higher reliability of the overall system. High temperature electronics can be improve performance measuring instrumentation for Thermal Protection Systems (TPS), integrated in embedded sensor plugs, to perform front-end signal conditioning and acquisition during atmospheric entry and descent. Thermal Protection System thickness and material characteristics affect the thermal exposure seen by such embedded electronics. The analysis in our examples illustrates scenarios from 150 deg C ambient, up to 260 deg C, with operating time ranging from 15 minutes to several hours. Venus in-situ environment poses different technical challenges, with ambient temperatures of 480 deg C and high pressures. The desired operating times in this environment are much longer, up to 90 days. Our presentation focuses on two of the technologies applied in our group: SiGe (silicon-germanium) for TPS applications, and GaN (gallium nitride) towards a Venus Lander. SiGe electronics for extreme environments (cryogenic temperatures) is being developed by a team led by Prof. Cressler from Georgia Tech, under the NASA RHESE (Radiation Hardened Electronics for Space Environments) program directed by Dr. Andrew Keys. GaN electronics for high temperatures are being developed by HRL. Summing up the numbers, these two technologies together are capable of spanning a range of temperatures of over 700 deg C. Examples from our recent validation tests in harsh environments illustrate the performance of the electronic components and modules. In addition to the SiGe or GaN-based semiconductor material, the characteristics, reliability and viability of the electronics is affected by constituent materials (metallization, dielectric layers) and by the packaging (die attach, wire bonding)

Spacesuit Integrated Carbon Nanotube Dust Removal System: A Scaled Prototype

Kavya Manyapu, University of North DakotaPablo De Leon, University of North DakotaLeora Peltz, The Boeing CompanyJames Gaier, NASAICES400: Extravehicular Activity: Space SuitsThe 48th International Conference on Environmental Systems was held in Albuquerque, New Mexico, USA on 08 July 2018 through 12 July 2018.Spacesuit dust mitigation has been a topic of high relevance and a critical path for future planetary exploration missions including Moon, Mars and Asteroids. A previous study demonstrated utilizing Carbon Nanotube (CNT) yarns as electrodes embedded into coupons made of spacesuit outer-layer material. When a multiphase Alternating Current (AC) voltage signal was applied to this material, the spacesuit fabric repelled greater than 80% lunar dust simulant with particle sizes between 10-75m in ambient conditions. As a continuation to this study, the feasibility of scaling the CNT embedded dust removal system on larger portions of spacesuit is investigated. A scaled prototype, representative of the knee joint section of a planetary spacesuit utilizing specifics of the NDX-2 lunar spacesuit developed by University of North Dakota was constructed. The outer-layer of this prototype is embedded with the CNT dust removal system and tested under various conditions. Fabrication of this system and results from the experiments using lunar dust simulant are detailed in this paper