Spacesuits are critical to human survival and exploration outside of the Earth’s protective environment. A number of environmental variables must be considered when designing a protective suit, which vary by location: Low Earth Orbit (LEO), Lunar Surface, or Mars Surface. Common to all the environments is the importance of a well-fitting suit, including gloves, in order to effectively and safely conduct EVA operations. During the Mercury, Gemini, Apollo, and Skylab programs, astronauts wore customized pressure suits and gloves. During the Shuttle era, astronauts were allocated to one of five general suit sizes: XS, S, M, L, and XL which were eventually reduced to 2 or 3 sizes. Shuttle EVA gloves varied between re-flight of standard sizes, to customized gloves. In spite of the customization of current EVA gloves, astronauts on the International Space Station (ISS) can experiencing strength degradation of over 50%, and many are experiencing finger injuries, including the loss of fingernails. The lack of significant performance improvement with current customization is confounding and the cause of the injuries are still largely unknown. Our objective is perform research to better understand the current “Fit” problems, which we believe will lead to customized suits and gloves which are designed to improve overall performance: enhance dexterity, reduce strength requirements, and minimize fatigue while still satisfying both thermal and micro-meteoroid requirements. Although many industries (e.g. aeronautics, automobile and apparel) are moving towards Digital Human Modelling (DHM) in order to design and fabricate with Finite Element Analyses (FEA), customization of current Phase VI gloves still generally begins with a manual measurement of each crew member’s hands in accordance with NASA Human Factor’s standards, followed by a mold casting which is scanned and measured. Manufacture of each glove is labor intensive. As far as the authors can determine, no dynamic digital analyses has been made of different hand configurations to characterize changes in measurements in order to design a glove with optimized fit from finger extension to tool grasp. In order to accomplish a future vision of scanning a hand in motion followed by rapid prototyping of a functionally optimized EVA glove, the Texas A&M University (TAMU) Aerospace Human Systems Laboratory (AHSL) recently acquired a 3dMD 3D Motion Capture system configured to capture 20 seconds of hand motion or 200 frames. While the final goal will be to develop digital scans which can be converted to FEA models, complete with skin properties, the objective of this paper is to report the results of comparing manual anthropometric hand measurements with those produced through the digital imaging of the 3dMD system and the results of converting the digital file into a 3D printed hand which replicates both the manual and 3dMD measurements. We are also exploring digital images with the Vitus Laser System. Initial results indicate that motion capture digital images may be used to accurately determine dimensional changes in a hand which provides a positive step towards DHM of the hand/EVA glove combination.
Technical Reports
The Microgravity Environment of the Space Shuttle Columbia Middeck During STS-32
Four hours of three-axis microgravity accelerometer data were successfully measured at the MA9F locker location in the Orbiter middeck of Columbia as part of the Microgravity Disturbances Experiment (MDE) on STS-32. These data were measured using the Honeywell In-Space Accelerometer, a small three-axis accelerometer that was hard-mounted onto the Fluid Experiment Apparatus to record the microgravity environment at the exact location of the MDE. Data were recorded during specific mission events such as Orbiter quiescent periods, crew exercise on the treadmill, and numerous Orbiter engine burns. Orbiter background levels were measured to be in the 3 x 10(exp -5) to 2 x 10(exp -4) G range, treadmill operations in the 6 x 10(exp -4) to 5 x 10(exp -3) G range, and Orbiter engine burns from 4 x 10(exp -3) to in excess of 1 x 10(exp -2) G. These data represent some of the first microgravity accelerometer data ever recorded in the middeck area of the Orbiter.
The Microgravity Environment of the Space Shuttle Columbia Payload Bay During STS-32
Over 11 hours of three-axis microgravity accelerometer data were successfully measured in the payload bay of Space Shuttle Columbia as part of the Microgravity Disturbances Experiment on STS-32. These data were measured using the High Resolution Accelerometer Package and the Aerodynamic Coefficient Identification Package which were mounted on the Orbiter keel in the aft payload bay. Data were recorded during specific mission events such as Orbiter quiescent periods, crew exercise on the treadmill, and numerous Orbiter engine burns. Orbiter background levels were measured in the 10(exp -5) G range, treadmill operations in the 10(exp -3) G range, and the Orbiter engine burns in the 10(exp -2) G range. Induced acceleration levels resulting from the SYNCOM satellite deploy were in the 10 (exp -2) G range, and operations during the pre-entry Flight Control System checkout were in the 10(exp -2) to 10(exp -1) G range.