Categorization of Select Cockpit Performance Evaluation Techniques.

INTRODUCTION: The modern aircraft cockpit has evolved into a complex system of systems. Numerous performance evaluation metrics and techniques exist that can measure the effectiveness of cockpit components in terms of how they influence the human operator's ability to perform tasks relevant to mission success. As no prior review of these metrics has been found in the literature, this effort attempts to do so, albeit without applying the metrics to a novel cockpit evaluation.METHODS: These metrics and techniques are discussed and presented in five defined categories as they relate to evaluating cockpit subsystems: ergonomics and anthropometrics; human-computer interaction; data management and presentation; crew resource management and operations; and ingress and egress.DISCUSSION: While this effort is significant and novel, it is not necessarily comprehensive. In conclusion, it is noted that no single holistic quantitative metric to evaluate cockpit design and performance yet exists. Utilizing some of the preexisting metrics presented to develop such a metric would be beneficial in efforts to evaluate aircraft cockpit designs and performance, as well as aiding future cockpit designs.Brighton EM, Klaus DM. Categorization of select cockpit performance evaluation techniques. Aerosp Med Hum Perform. 2023; 94(9):696-704.

Side-by-Side Comparison of Human Perception and Performance Using Augmented, Hybrid, and Virtual Reality.

Alternative reality (XR) technologies, including physical, augmented, hybrid, and virtual reality, offer ways for engineered spaces to be evaluated. Traditionally, practitioners (such as those designing spacecraft habitats) have relied on physical mockups to perform such design evaluations, but digital XR technologies present several streamlining advantages over their physical counterparts. These digital environments vary in their level of virtuality, and consequently have different effects on human perception and performance, with respect to a completely physical mockup environment. To date, very little has been done to characterize and quantify such differences in human perception and performance across XR environments of equal fidelity for the same end application. Here, we show that perception and performance in the virtual reality environment most closely mirror those in the physical reality environment, as measured through volumetric assessment and functional task experiments. These experiments required subjects to judge the dimensions of 3D objects and perform operational tasks presented via checklists. Our results highlight the potential for virtual reality systems to accelerate the iterative design of engineered spaces relative to the use of physical mockups, while preserving the human perception and performance characteristics of a completely physical environment. These findings also elucidate specific advantages and disadvantages to specific digital XR technologies with respect to one another and the physical reality baseline. Practitioners may inform their selection of an XR modality for their specific end application based on this comparative analysis, as it contextualizes the niche for each technology in the realm of iterative design for engineered spaces.

Space microbiology.

The responses of microorganisms (viruses, bacterial cells, bacterial and fungal spores, and lichens) to selected factors of space (microgravity, galactic cosmic radiation, solar UV radiation, and space vacuum) were determined in space and laboratory simulation experiments. In general, microorganisms tend to thrive in the space flight environment in terms of enhanced growth parameters and a demonstrated ability to proliferate in the presence of normally inhibitory levels of antibiotics. The mechanisms responsible for the observed biological responses, however, are not yet fully understood. A hypothesized interaction of microgravity with radiation-induced DNA repair processes was experimentally refuted. The survival of microorganisms in outer space was investigated to tackle questions on the upper boundary of the biosphere and on the likelihood of interplanetary transport of microorganisms. It was found that extraterrestrial solar UV radiation was the most deleterious factor of space. Among all organisms tested, only lichens (Rhizocarpon geographicum and Xanthoria elegans) maintained full viability after 2 weeks in outer space, whereas all other test systems were inactivated by orders of magnitude. Using optical filters and spores of Bacillus subtilis as a biological UV dosimeter, it was found that the current ozone layer reduces the biological effectiveness of solar UV by 3 orders of magnitude. If shielded against solar UV, spores of B. subtilis were capable of surviving in space for up to 6 years, especially if embedded in clay or meteorite powder (artificial meteorites). The data support the likelihood of interplanetary transfer of microorganisms within meteorites, the so-called lithopanspermia hypothesis.

Antibiotic efficacy and microbial virulence during space flight.

Human space flight is a complex undertaking that entails numerous technological and biomedical challenges. Engineers and scientists endeavor, to the extent possible, to identify and mitigate the ensuing risks. The potential for an outbreak of an infectious disease in a spacecraft presents one such concern, which is compounded by several components unique to an extraterrestrial environment. Various factors associated with the space flight environment have been shown to potentially compromise the immune system of astronauts, increase microbial proliferation and microflora exchange, alter virulence and decrease antibiotic effectiveness. An acceptable resolution of the above concerns must be achieved to ensure safe and efficient space habitation. To help bring this about, scientists are employing advances in biotechnology to better characterize the relevant variables and establish appropriate solutions. Because many of these clinical concerns are also relevant in terrestrial society, this research will have reciprocal benefits back on Earth.

Preflight virtual reality training as a countermeasure for space motion sickness and disorientation.

INTRODUCTION: Research suggests that preflight training in virtual reality devices can simulate certain aspects of microgravity and may prove to be an effective countermeasure for space motion sickness (SMS) and spatial disorientation (SD). It is hypothesized that exposing subjects preflight to variable virtual orientations, similar to those encountered during spaceflight, will reduce the incidence and/or severity of SMS and SD. METHODS: Subjects were assigned to either a variable training (VT) or nonvariable training (NVT) condition to perform a simple navigation and switch activation task in a virtual space station. VT subjects performed the task starting in several different orientations, whereas NVT subjects always performed the task starting in the same orientation. On a separate day, all subjects then performed the same task in a transfer of training session starting from a novel orientation. RESULTS: When exposed to the novel test orientation, VT subjects performed the tasks more quickly (12%) and with fewer nausea symptoms (53%) than during the training session, compared with NVT subjects who performed more slowly (6%) and with more nausea symptoms (28%). Both VT and NVT conditions were effective in reducing the number of wall hits in the novel orientation (39% and 34%, respectively). DISCUSSION: These results demonstrate the effectiveness of using variable training in a virtual environment for reducing nausea and improving task performance in potentially disorienting surroundings, and suggest that such training may be developed into an effective countermeasure for SMS, SD, and associated performance decrements that occur in spaceflight.

An ultrasonic methodology for muscle cross section measurement to support space flight.

The number one priority for any manned space mission is the health and safety of its crew. The study of the short and long term physiological effects on humans is paramount to ensuring crew health and mission success. One of the challenges associated in studying the physiological effects of space flight on humans, such as loss of bone and muscle mass, has been that of readily attaining the data needed to characterize the changes. The small sampling size of astronauts, together with the fact that most physiological data collection tends to be rather tedious, continues to hinder elucidation of the underlying mechanisms responsible for the observed changes that occur in space. Better characterization of the muscle loss experienced by astronauts requires that new technologies be implemented. To this end, we have begun to validate a 360 degree ultrasonic scanning methodology for muscle measurements and have performed empirical sampling of a limb surrogate for comparison. Ultrasonic wave propagation was simulated using 144 stations of rotated arm and calf MRI images. These simulations were intended to provide a preliminary check of the scanning methodology and data analysis before its implementation with hardware. Pulse-echo waveforms were processed for each rotation station to characterize fat, muscle, bone, and limb boundary interfaces. The percentage error between MRI reference values and calculated muscle areas, as determined from reflection points for calf and arm cross sections, was -2.179% and +2.129%, respectively. These successful simulations suggest that ultrasound pulse scanning can be used to effectively determine limb cross-sectional areas. Cross-sectional images of a limb surrogate were then used to simulate signal measurements at several rotation angles, with ultrasonic pulse-echo sampling performed experimentally at the same stations on the actual limb surrogate to corroborate the results. The objective of the surrogate sampling was to compare the signal output of the simulation tool used as a methodology validation for actual tissue signals. The disturbance patterns of the simulated and sampled waveforms were consistent. Although only discussed as a small part of the work presented, the sampling portion also helped identify important considerations such as tissue compression and transducer positioning for future work involving tissue scanning with this methodology.

Extracellular mass transport considerations for space flight research concerning suspended and adherent in vitro cell cultures.

Conducting biological research in space requires consideration be given to isolating appropriate control parameters. For in vitro cell cultures, numerous environmental factors can adversely affect data interpretation. A biological response attributed to microgravity can, in theory, be explicitly correlated to a specific lack of weight or gravity-driven motion occurring to, within or around a cell. Weight can be broken down to include the formation of hydrostatic gradients, structural load (stress) or physical deformation (strain). Gravitationally induced motion within or near individual cells in a fluid includes sedimentation (or buoyancy) of the cell and associated shear forces, displacement of cytoskeleton or organelles, and factors associated with intra- or extracellular mass transport. Finally, and of particular importance for cell culture experiments, the collective effects of gravity must be considered for the overall system consisting of the cells, their environment and the device in which they are contained. This does not, however, rule out other confounding variables such as launch acceleration, on orbit vibration, transient acceleration impulses or radiation, which can be isolated using onboard centrifuges or vibration isolation techniques. A framework is offered for characterizing specific cause-and-effect relationships for gravity-dependent responses as a function of the above parameters.

A modular suite of hardware enabling spaceflight cell culture research.

BioServe Space Technologies, a NASA Research Partnership Center (RPC), has developed and operated various middeck payloads launched on 23 shuttle missions since 1991 in support of commercial space biotechnology projects. Modular cell culture systems are contained within the Commercial Generic Bioprocessing Apparatus (CGBA) suite of flight-qualified hardware, compatible with Space Shuttle, SPACEHAB, Spacelab and International Space Station (ISS) EXPRESS Rack interfaces. As part of the CGBA family, the Isothermal Containment Module (ICM) incubator provides thermal control, data acquisition and experiment manipulation capabilities, including accelerometer launch detection for automated activation and thermal profiling for culture incubation and sample preservation. The ICM can accommodate up to 8 individually controlled temperature zones. Command and telemetry capabilities allow real-time downlink of data and video permitting remote payload operation and ground control synchronization. Individual cell culture experiments can be accommodated in a variety of devices ranging from 'microgravity test tubes' or standard 100 mm Petri dishes, to complex, fed-batch bioreactors with automated culture feeding, waste removal and multiple sample draws. Up to 3 levels of containment can be achieved for chemical fixative addition, and passive gas exchange can be provided through hydrophobic membranes. Many additional options exist for designing customized hardware depending on specific science requirements.

Microgravity materials and life sciences research applications of digital holography.

We investigate the utility of digital holographic interferometry for analyzing gravity-dependent mass transport phenomena as applicable to materials and life science research topics. Digital holography is useful for measurement of parameters that introduce phase changes in light traversing the material of interest, such as temperature or concentration variations in an aqueous environment. We have constructed, tested, and verified a compact, portable digital holographic monitor (DHM) suitable for characterization of transparent samples. It has proved useful for the study of systems such as protein crystal growth solutions and has been proposed for further application into studies involving microbial metabolism. The DHM is also sufficiently rugged for field operation in challenging environments a s may be encountered in a spacecraft or industrial setting. We discuss some system capabilities and limitations.