Mars Desert Research Station
Habitable Volume Efficiency
NSBE MDRS Mission Proposal
Submitted by: Dr. Robert Howard
1. Executive Summary
The purpose of this evaluation is to determine the efficiency of habitable volume of the Mars Desert Research Station with unsuited (shirt sleeve) participants and to obtain preliminary human performance data to assist in future planetary habitat designs and assessments.
Most concepts for human missions to Mars require a surface stay in the vicinity of 500 days. During this time the crew will be on the Martian surface without possibility of an early return to Earth. The habitat must support all of the crew’s needs during this time, including but not limited to sleep, hygiene, recreation, medical care, laboratory work, meal preparation and eating, maintenance, and communications. The degree to which the internal volume of the habitat facilitates these tasks can impact the overall livability of the habitat for this mission.
This evaluation will measure the ability of the habitat to support day in the life tasks of a Martian expedition crew by means of physical measurements of its Net Habitable Volume, exploration of use of space, architectural improvements, and questionnaires to be completed by the expedition crew.
2. Research Description
This research will utilize the six MDRS expedition crew as test subjects in a 14-day evaluation of the habitability of the MDRS habitat. To obtain test data, several human factors measures will be conducted as described in Section 5 of this proposal. Various questionnaires and rating scales will be used by test subjects to rate the habitability of various sections of the habitat and tasks performed by the crew. Participants will also provide architectural assessments of the habitat.
This real-time data collection will be performed as the crew conducts their duties as members of the expedition crew. Some information will be collected as various tasks are performed, while others will be collected at the beginning and end of each day. Data will be archived in a web-based storage application for post-mission analysis.
3. Research Importance
At the beginning of any human spacecraft design project, engineers need to know how large the pressure vessel needs to be. The size and dimensions of the pressure vessel have significant repercussions throughout the vehicle. A vehicle that is too large imposes unnecessary constraints on the propulsion, life support, power, and thermal systems. A vehicle that is too small may physically prevent the crew from conducting required tasks or may create a psychologically intolerable environment.
Despite the seriousness of the need, there is very little concrete data to define how large a spacecraft pressurized volume must be. Most volumetric studies were conducted in the sixties, with extrapolations and assumptions that call into question the validity of any conclusions projected into the 500-day surface stays currently assumed for Mars missions.
Current work at NASA for the Constellation Lunar Outpost has produced concepts varying in pressurized volume from as small as 55 m3 to as large as 500 m3, roughly a factor of ten difference. Generating additional human factors data from analogues such as MDRS could be helpful in NASA Constellation activity as well as future NASA Mars mission design.
Finally, results of this investigation will feed into ongoing NSBE research related to the Space Special Interest Group’s Project Arusha. This large scale lunar design project has yet to develop concepts for lunar habitation elements. Results of this research will help scale the size of Project Arusha habitat concepts.
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4. Literature Review of Similar Research
Very little research has been published related to habitability studies for long duration planetary outposts. Much work was conducted in the 1960s, including several short duration studies that were extrapolated to produce volume vs. duration charts contained within NASA-STD-3000. However, there is little to no correlation between these charts and the actual volumes of long duration spacecraft that have been flown by the United States, Russia, and the Soviet Union. This discongruence has led NASA to initiate several studies in recent years, most of which are unpublished.
The Habitability Design Center at NASA Johnson Space Center has conducted habitability evaluations of several lunar habitat mockups. Most recently, four basic concepts have been assessed: an ISS-derived horizontal habitat, a small-diameter horizontal habitat, a large diameter multi-deck vertical habitat, and the Habitat Demonstration Unit - a medium-diameter single deck vertical habitat. (A horizontal habitat is a cylindrical pressure vessel where the floor is perpendicular to the circular cross section - e.g. an aircraft fuselage or a railroad tanker car. In the case of a vertical habitat, the floor is parallel to the circular cross section - e.g. a Lighthouse.)
ISS-Derived Horizontal Habitat
This concept was based on the idea of using the ~4.2 meter diameter ISS Lab Module structural test article (originally intended for use as the now-cancelled ISS Hab Module) and outfitting it as a Lunar Outpost. A mockup of this volume was constructed in 2005 at Johnson Space Center by the Lunar Habitat Mockups Project and evaluated. The diameter allowed the habitat to be divided into an upper and lower deck. Habitability data was collected regarding crew quarters, hygiene, galley, medical, exercise, EVA, training, science, housekeeping/maintenance, and stowage.
Some concerns raised during the evaluation of this concept included utilizing a more detailed mission definition and “day in the life” scenarios. Conducted in 2-4 hour segments, this evaluation was limited in its ability to capture all crew functions - a liability that will not be present in this proposed study where the entire 14-day mission will produce data.
Small Diameter Horizontal Habitat
The smallest habitat concept mocked up to date, this mockup was based on three concepts for 3.0 meter diameter and 3.5 meter diameter single deck habitat modules developed by the Lunar Architecture Team and Lunar Surface Systems Habitat Functional Element Team. The objective was to conduct a comparative evaluation of a crew quarters module with the two diameters. Two mockups were constructed, each 5 meters in length, each with one of the aforementioned diameters. Unlike the other mockups, this was not intended to reflect a complete lunar Outpost, only one module in an outpost to be composed of several linked modules. Consequently, a limited subset of tasks were evaluated in these mockups, namely those which could conceivably be performed in a crew quarters area of an outpost.
This evaluation rated the 3.5 meter diameter habitat as more habitable than the 3.0 meter, as might be expected. However, some interesting aspects were also uncovered. The larger diameter resulted in an increased ceiling height, which resulted in some of the internal architecture being too high for shorter crew members to reach. Additionally, the curvature of the walls in both mockups created problems in the WCS (bathroom) area. Because the architecture was based on a central aisle with crew stations to either side, both modules exhibited a “tunnel” effect, which created a sense of crowding in the 3.0 meter diameter but was not as bad in the 3.5 meter diameter. The 3.5 meter diameter revealed an ability to break away from this architecture (as was done in some sections of the ISS-Derived Horizontal Habitat), but it was not utilized in this mockup.
Vertical Habitat
This approach was based on a Mars-forward desire to maximize habitable volume by using the entire (expected) launch shroud diameter, which at the time was projected to be 8.4 meters in diameter. This concept was a two-deck habitat. The outfitting for this habitat borrowed from several vertical habitat outpost concepts studied by the Lunar Architecture Team and its successor, the Lunar Surface Systems Habitat Functional Element Team. This mockup is roughly similar in dimensions to the Mars Desert Research Station.
Habitat Demonstration Unit
This approach was based on the NASA Lunar Surface Scenario 12.1 surface habitation architecture and is a laboratory module measuring 5 meters in diameter. This single deck habitat is the core module in a multi-module lunar outpost configuration. The module consisted of an airlock and four primary workstations: General Maintenance, EVA Suit Maintenance, Medical Operations, and Geology Science. This module was tested north of Flagstaff, Arizona as part of NASA’s 2010 Desert RATS (Research and Technology Studies). This 14-day test did not involve overnight stays in the module but included daily work shifts at each of the workstations, conducted by astronauts, geologists, and engineers.
Analysis of evaluation data from this habitat concept is currently in-work at Johnson Space Center.
5. Experiment Design
This research will follow the methodology developed under my supervision by the NASA Habitability and Human Factors Branch for the evaluation of spacecraft mockups.
Participants will be briefed on the test procedures and run through a familiarization session before the start of the expedition. This will ensure that the participant is fully aware of the test objectives and prepared to perform his or her duties throughout the test. A human research consent form will be explained and signed by each test participate before testing commences (Appendix D and E). It is anticipated that NSBE will conduct this research under the auspices of NASA’s Usability Testing and Analysis Facility, which has approval from the NASA/JSC Committee for Protection of Human Subjects (CPHS) to conduct investigations and research with human test participants.
Success criteria is defined as achieving suitable habitable volume for performance efficiency through the MDRS habitat for 6 unsuited participants. Failure is defined as not having suitable habitable volume in the habitat for 6 unsuited participants. The following human factors measures will assist in identifying the level of success and failure:
· Likert Scale Human Factors Real-Time and Post Evaluation Questionnaires - Use a 1-5 scales to assess features such as usability, performance, difficulty, and suitability. Some are completed during the mission, while others are completed at end of mission.
· Card Sort Analysis - A graphical method to allow participants to organize the habitat internal layout in ways that make sense to them.
· Volumetric Analysis - A measurement of the Net Habitable Volume of the MDRS habitat using a method developed by NASA Johnson Space Center
· Video/Audio Capture - Select activities will be recorded to collect task time, interference, and performance data
Required equipment includes:
· Computer with CAD software
· Videocameras
· Digital cameras
· Angle-measurement devices
· Tape measures
· MDRS Habitat
· Mission-specific equipment and supplies
Required personnel (must be on crew):
· Human Factors and Habitation Engineer
· CAD-proficient expedition crew member
· All other MDRS crew members
6. Data Analysis
During and after the expedition, participants will be asked to complete a Likert Scale Human Factors Questionnaires using a 1-5 Likert scale with the anchor points being “1” Unacceptable, “3” Borderline, and “5” Acceptable. This data will be compiled and analyzed for statistical significance after the expedition.
At the end of the first day, each will be asked to complete a card sorting task of the habitat’s internal architecture. They will make revisions to their card sort at the end of each subsequent day and at the end of the expedition. Open-ended questions will allow the crew member to explain his or her reasoning. Each reconfiguration will be archived. These suggested architectures will be assessed in light of the tasks performed by the crew member that day.
A detailed geometric measurement of the MDRS habitat will be used by the CAD-proficient crew member to create a CAD model of the MDRS and its internal architecture. This will be measured using the NASA JSC process to calculate the Net Habitable Volume of the habitat.
Video/Audio data collection will be reviewed after the expedition to provide information about what the participants saw and did in the habitat. These files will be examined for performance, human flow patterns, and item reconfiguration.
These data sets will be analyzed for strengths and weaknesses of the MDRS total volume, as well as its use of volume with respect to internal layout, workstation design, equipment and stowage accommodations, and crew psychosocial tolerance.
7. Publication Plan
Depending on the timing of the completion of this research, any of several technical conferences may be suitable for presentation of papers and/or posters. A technical paper is to be completed within two months of the expedition and pending timing, may be submitted to one of the following conferences:
NSBE Aerospace Systems Conference - February (bi-annual)
AIAA Earth & Space - March (bi-annual)
International Conference on Environmental Systems - July (annual)
Human Factors and Ergonomics Society - September (annual)
Additionally, the research will be published in a NASA Technical Memorandum, to ensure that the data is accessible to NASA habitation engineers.
Finally, a briefing of report conclusions will be provided to several NASA offices, including the Habitability and Human Factors Branch and the Habitation Functional Element Team.
8. Crew Member Application
I seek a posting to the NSBE MDRS Expedition Crew as a Human Factors and Habitation Engineer. I hold a doctorate in Aerospace Engineering and a masters in Industrial Engineering with a focus in Human Factors. I have four years’ experience in the NASA Habitability and Human Factors Branch, where I manage the NASA Habitability Design Center. I have managed habitability evaluations for the Orion Crew Exploration Vehicle, Altair Lunar Lander, Small Pressurized Rover, and Lunar Outpost.
My personal dedication to the cause of human Mars exploration and the participation of Black space explorers in extraterrestrial endeavors is exemplified by my work as founder and Director of the NSBE Space SIG and as founder and President of the NSBE Houston Space Chapter. I have committed substantial time, effort, and money to NSBE’s advancement of the space program and its connection to the Black community, including the implementation of this project. I have worked since childhood to contribute to the human exploration and settlement of space and look forward to NSBE having a role in the one-day real exploration of the planet Mars.
I am fully prepared for the discipline and mission protocols required to support a simulated Mars mission and will participate fully in all training exercises and activities developed by the Mission Commander and Executive Officer. I look forward to the tough working and living conditions of MDRS and am excited about the opportunity to serve in this capacity.