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Bowie, Jonathan T.

Publications and source records attributed to Bowie, Jonathan T..

Asteroid Redirect Crewed Mission Space Suit and EVA System Maturation

The Asteroid Redirect Crewed Mission (ARCM) requires a Launch/Entry/Abort (LEA) suit capability and short duration Extra Vehicular Activity (EVA) capability from the Orion spacecraft. For this mission, the pressure garment that was selected, for both functions, is the Modified Advanced Crew Escape Suit (MACES) with EVA enhancements and the life support option that was selected is the Exploration Portable Life Support System (PLSS). The proposed architecture was found to meet the mission constraints, but much more work is required to determine the details of the required suit upgrades, the integration with the PLSS, and the rest of the tools and equipment required to accomplish the mission. This work has continued over the last year to better define the operations and hardware maturation of these systems. EVA simulations have been completed in the NBL and interfacing options have been prototyped and analyzed with testing planned for late 2014. For NBL EVA simulations, in 2013, components were procured to allow in-house build up for four new suits with mobility enhancements built into the arms. Boots outfitted with clips that fit into foot restraints have also been added to the suit and analyzed for possible loads. Major suit objectives accomplished this year in testing include: evaluation of mobility enhancements, ingress/egress of foot restraint, use of foot restraint for worksite stability, ingress/egress of Orion hatch with PLSS mockup, and testing with two crew members in the water at one time to evaluate the crew's ability to help one another. Major tool objectives accomplished this year include using various other methods for worksite stability, testing new methods for asteroid geologic sampling and improving the fidelity of the mockups and crew equipment. These tests were completed on a medium fidelity capsule mockup, asteroid vehicle mockup, and asteroid mockups that were more accurate for an asteroid type EVA than previous tests. Another focus was the design and fabrication of the interface between the MACES and the PLSS. The MACES was not designed to interface with a PLSS, hence an interface kit must accommodate the unique design qualities of the MACES and provide the necessary life support function connections to the PLSS. A prototype interface kit for MACES to PLSS has been designed and fabricated. Unmanned and manned testing of the interface will show the usability of the kit while wearing a MACES. The testing shows viability of the kit approach as well as the operations concept. The design will be vetted through suit and PLSS experts and, with the findings from the testing, the best path forward will be determined. As the Asteroid Redirect Mission matures, the suit/life support portion of the mission will mature along with it and EVA Tools & Equipment can be iterated to accommodate the overall mission objectives and compromises inherent in EVA Suit optimization. The goal of the EVA architecture for ARCM is to continue to build on the previously developed technologies and lessons learned, and accomplish the ARCM EVAs while providing a stepping stone to future missions and destinations.

Bowie, Jonathan T.↗

Extensibility of Human Asteroid Mission to Mars and Other Destinations

This paper will describe the benefits of execution of the Asteroid Redirect Mission as an early mission in deep space, demonstrating solar electric propulsion, deep space robotics, ground and on-board navigation, docking, and EVA. The paper will also discuss how staging in trans-lunar space and the elements associated with this mission are excellent building blocks for subsequent deep space missions to Mars or other destinations.

McDonald, Mark A.↗

Extravehicular Activity Asteroid Exploration and Sample Collection Capability

One of the challenging primary objectives associated with NASA's Asteroid Redirect Crewed Mission (ARCM) is to demonstrate deep space Extravehicular Activity (EVA) and tools and to obtain asteroid samples to return to Earth for further study. Prior Shuttle and International Space Station (ISS) spacewalks have benefited from engineered EVA interfaces which have been designed and manufactured on Earth. Rigid structurally mounted handrails, and tools with customized interfaces and restraints optimize EVA performance. For ARCM, EVA complexity increases due to the uncertainty of the asteroid properties. The variability of rock size, shape and composition, as well as behavior of the asteroid capture mechanism will complicate EVA translation, tool restraint, and body stabilization. The unknown asteroid hardness and brittleness will complicate tool use. The rock surface will introduce added safety concerns for cut gloves and debris control. Feasible solutions to meet ARCM EVA objectives were identified using experience gained during Apollo, Shuttle, and ISS EVAs, terrestrial mountaineering practices, NASA Extreme Environment Mission Operations (NEEMO) 16 mission, and during Neutral Buoyancy Laboratory testing in the Modified Advanced Crew Escape Suit (MACES) suit. This paper will summarize the overall operational concepts for conducting EVAs for the ARCM mission including translation paths and body restraint methods, potential tools used to extract the samples, design implications for the Asteroid Redirect Vehicle (ARV) for EVA, and the results of early development testing of potential EVA tasks.

Sipila, Stephanie A.↗

Asteroid Redirect Crewed Mission Space Suit and EVA System Architecture Trade Study

The Asteroid Redirect Crewed Mission (ARCM) requires a Launch/Entry/Abort (LEA) suit capability and short duration Extra Vehicular Activity (EVA) capability for Orion. The EVAs will involve a two-person crew for approximately four hours. Currently, two EVAs are planned with one contingency EVA in reserve. Providing this EVA capability is very challenging due to system level constraints and a new and unknown environment. The goal of the EVA architecture for ARCM is one that builds upon previously developed technologies and lessons learned, and that accomplishes the ARCM mission while providing a stepping stone to future missions and destinations. The primary system level constraints are to 1) minimize system mass and volume and 2) minimize the interfacing impacts to the baseline Orion design. In order to minimize the interfacing impacts and to not perturb the baseline Orion schedule, the concept of adding "kits" to the baseline system is proposed. These kits consist of: an EVA kit (converts LEA suit to EVA suit), EVA Servicing and Recharge Kit (provides suit consumables), the EVA Tools, Translation Aids & Sample Container Kit (the tools and mobility aids to complete the tasks), the EVA Communications Kit (interface between the EVA radio and the MPCV), and the Cabin Repress Kit (represses the MPCV between EVAs). This paper will focus on the trade space, analysis, and testing regarding the space suit (pressure garment and life support system). Historical approaches and lessons learned from all past EVA operations were researched. Previous and current, successfully operated EVA hardware and high technology readiness level (TRL) hardware were evaluated, and a trade study was conducted for all possible pressure garment and life support options. Testing and analysis was conducted and a recommended EVA system architecture was proposed. Pressure garment options that were considered for this mission include the currently in-use ISS EVA Mobility Unit (EMU), all variations of the Advanced Crew Escape Suit (ACES), and the Exploration Z-suit. For this mission, the pressure garment that was selected is the Modified ACES (MACES) with EVA enhancements. Life support options that were considered included short closed-loop umbilicals, long open-loop umbilicals, the currently in-use ISS EMU Portable Life Support System (PLSS), and the currently in development Exploration PLSS. For this mission, the life support option that was selected is the Exploration PLSS. The greatest risk in the proposed architecture is viewed to be the comfort and mobility of the baseline MACES and the delicate balance between adding more mobility features while not compromising landing safety. Feasibility testing was accomplished in low fidelity analogs and in the JSC Neutral Buoyancy Laboratory (NBL) to validate the concept before a final recommendation on the architecture was made. The proposed architecture was found to meet the mission constraints, but much more work is required to determine the details of the required suit upgrades, the integration with the PLSS, and the rest of the tools and equipment required to accomplish the mission. This work and further definition of the remaining kits will be conducted in government fiscal year 14.

Blanco, Raul A.↗

Asteroid Redirect Crewed Mission Space Suit and EVA System Architecture Trade Study

This paper discusses the Asteroid Redirect Crewed Mission (ARCM) space suit and Extravehicular Activity (EVA) architecture trade study and the current state of the work to mature the requirements and products to the mission concept review level. The mission requirements and the resulting concept of operations will be discussed. A historical context will be presented as to present the similarities and differences from previous NASA missions. That will set the stage for the trade study where all options for both pressure garment and life support were considered. The rationale for the architecture decisions will then be presented. Since the trade study did identity risks, the subsequent tests and analyses that mitigated the risks will be discussed. Lastly, the current state of the effort will be provided.

Bowie, Jonathan T.↗

Extravehicular Activity Asteroid Exploration and Sample Collection Capability

One of the challenging primary objectives associated with NASA's Asteroid Redirect Crewed Mission (ARCM) is to demonstrate deep space Extravehicular Activity (EVA) and tools and to obtain asteroid samples to return to Earth for further study. Prior Shuttle and International Space Station (ISS) spacewalks have benefited from engineered EVA interfaces which have been designed and manufactured on Earth. Rigid structurally mounted handrails, and tools with customized interfaces and restraints optimize EVA performance. For ARCM, EVA complexity increases due to the uncertainty of the asteroid properties. The variability of rock size, shape and composition, as well as behavior of the asteroid capture mechanism will complicate EVA translation, tool restraint, and body stabilization. The unknown asteroid hardness and brittleness will complicate tool use. The rock surface will introduce added safety concerns for cut gloves and debris control. Feasible solutions to meet ARCM EVA objectives were identified using experience gained during Apollo, Shuttle, and ISS EVAs, terrestrial mountaineering practices, NASA Extreme Environment Mission Operations (NEEMO) 16 mission, and during Neutral Buoyancy Laboratory testing in the Modified Advanced Crew Escape Suit (MACES) suit. This paper will summarize the overall operational concepts for conducting EVAs for the ARCM mission including translation paths and body restraint methods, potential tools used to extract the samples, design implications for the Asteroid Redirect Vehicle (ARV) for EVA, and the results of early development testing of potential EVA tasks.

Sipila, Stephanie A.↗