Mission Control Research Articles

HF01-11 TRIALS OF VOIDING IN SPACE: HOW URINE SHAPED THE DEVELOPMENT OF SPACESUITS

You have accessJournal of UrologyCME1 Apr 2023HF01-11 TRIALS OF VOIDING IN SPACE: HOW URINE SHAPED THE DEVELOPMENT OF SPACESUITS Aaron Huang, Jacob Gaines, and Jason Kim Aaron HuangAaron Huang More articles by this author , Jacob GainesJacob Gaines More articles by this author , and Jason KimJason Kim More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003243.11AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: The Space Race, a competition between the United States and the Soviet Union to send a man to the moon, captured the world’s attention in the 1960s. While tensions between the nations ran high, one main focus of NASA scientists was on how to design a spacesuit to handle this harsh, new environment. These suits were created in the most practical fashion – to preserve pressures at high altitudes and protect its wearer. However, they were not created to facilitate voiding as “the first space man is not expected to have ‘to go’,” said a NASA official at the time. METHODS: A review was conducted on the history of the development of space suits using Google and Google Scholar. RESULTS: When it came to the first American in space, Alan Shepard was ready for the mission, undergoing vigorous training, both physical and psychological. What he and the crew were not prepared for on that fateful day of May 5th, 1961 were delays that led to long times spent sitting in his spacesuit waiting for launch. Shepard, unable to hold back his urine much longer, got the approval from mission control to relieve himself in the suit, short-circuiting certain monitors for his vitals. Researchers looked into other approaches to collecting urine; suprapubic and indwelling catheters were swiftly rejected due to discomfort as well as the risk for infection. The second American in space, Gus Grissom, made his own urine reservoir with two pairs of rubber pants, containing the urine between the layers, a creative yet quite impractical method. NASA, seeking to improve the current suit in terms of a urinary collecting device, looked towards the real world for people that lived with impaired detrusor activity to the purchase of a rubber urinal. Engineers created a complex valve on this device that would allow the astronaut to raise the intra-suit pressure when urinating, thus forcing the urine into the storage container, to counteract zero gravity. CONCLUSIONS: Today, maximally absorbent fabrics are utilized by astronauts as their urinary collecting devices that wick off and recycle urine. It was through Shepard’s unplanned trial of voiding into his suit that led to NASA understanding the need for urinary collecting devices, which have come a long way over the past half century. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e259 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Aaron Huang More articles by this author Jacob Gaines More articles by this author Jason Kim More articles by this author Expand All Advertisement PDF downloadLoading ...

The Woman in the Moon: How Margaret Hamilton Helped Fly the First Astronauts to the Moon by Richard Maurer

Reviewed by: The Woman in the Moon: How Margaret Hamilton Helped Fly the First Astronauts to the Moon by Richard Maurer Kara Forde Maurer, Richard The Woman in the Moon: How Margaret Hamilton Helped Fly the First Astronauts to the Moon. Roaring Brook, 2023 [272p] illus. with photographs Trade ed. ISBN 9781626728561 $19.99 E-book ed. ISBN 9781626728578 $10.99 Reviewed from digital galleys R Gr. 6-9 Media attention on NASA’s Apollo programs often focused on the star power of the astronauts and mission control, overlooking how crucial the Apollo Guidance Computer (AGC) was to the success of the astonishing missions to the moon. Margaret Hamilton, the woman who rose through the ranks to become responsible for all the AGC’s software, is similarly overlooked, but her role was just as essential. This well-structured biography of Hamilton gives readers a glimpse into the revolutionary endeavor to write computer code that would enable the Apollo spacecrafts to fly almost autonomously. After a short prologue introduces readers to President Kennedy’s goal to get a man on the moon by the end of the 1960s, the book chronologically details Hamilton’s early life and the ways it influenced her career, including her interest in abstract mathematics and her leadership experience managing a tourist attraction in Michigan. The more riveting reading occurs in the later portions of the book, as Maurer describes Hamilton’s fascinating accomplishments in the fledgling field of computer coding. Maurer’s writing style is engaging, and he manages to make even the most complicated subjects accessible. Scattered throughout the main narrative are brief descriptions of STEM topics that supplement the information more closely related to Hamilton’s life, as are many distinctive black-and-white archival photographs. The acknowledgements reveal that Maurer’s first-hand conversations with Hamilton formed the basis of this biography; other back matter includes a timeline, end notes for textual references, a bibliography of oral histories, books, and articles, and an index to come. [End Page 229] Copyright © 2023 The Board of Trustees of the University of Illinois

Integrated guidance and control of hypersonic flight vehicle with coordinated mission requirement and input constraint

An integrated adaptive guidance and control algorithm is investigated for the hypersonic flight vehicle (HFV) under the objection of coordinated for mission requirement and control capability. The design pressure to avoid input saturation is placed in the guidance loop by analyzing the hard restriction on the fuel-air equivalence ratio (FER) and the acceleration mission objective. Using the concept of model self-shaping, a loss function is established to achieve the self-optimization of the reference model bandwidth. The reference trajectory of the velocity slows down as the FER approaches its maximum value and becomes faster as the FER demand decreases. The backstepping frame is applied in the attitude control system, and the dynamics uncertainty with the unknown aerodynamic parameters is constructed using neural network. The Karush–Kuhn–Tucker multiplier is used as a link parameter of the guidance and control integrated framework and is introduced into the adaptive update law. An adaptive algorithm is proposed with the estimating evaluation derived from the serial-parallel estimation model. A HFV simulation test with FER constraint shows that the adaptive integrated guidance and control can follow the desired trajectory with high tracking accuracy, and the control input can be kept within a feasible value.

ОСНОВНЫЕ ФЕНОМЕНЫ ОБЩЕНИЯ КОСМОНАВТОВ В КОММУНИКАТИВНОЙ СИСТЕМЕ «ЭКИПАЖ – ЦЕНТР УПРАВЛЕНИЯ ПОЛЕТАМИ» И НЕОБХОДИМОСТЬ ЕЕ МОДИФИКАЦИИ

The paper describes several phenomena of the crew – Mission control center (MCC) communication system established in space experiment KONTENT that attributable to cosmonauts' psycho-emotional conditions and necessitating the socio-psychological support. The authors propound their vision of social psychological support in context of the intergroup communication, as well as thoughts of how the crew-MCC communication can be improved. The recommended approaches will enable continuous psychological support to cosmonauts in orbit and reduce the psycho-emotional strain in MCC operators.

ОСОБЕННОСТИ СТИЛЕЙ ОБЩЕНИЯ КОСМОНАВТОВ С ЦЕНТРОМ УПРАВЛЕНИЯ ПОЛЕТАМИ ПРИ РАЗЛИЧНОМ УРОВНЕ РАБОЧЕЙ НАГРУЗКИ

Space experiment CONTENT was focused on studying the spacecrews communication with the Mission control center (MCC) using the content-analysis methodology. It was established that on hard work days the amount of communication increased, as did the frequency of coping strategies. Models of communication styles and coping analysis used in data interpretation were adequate for description of the crew-MCC interactions during usual and intensive work loads. In the course of critical operations, such as EVA, docking etc., or emergencies profiles of the coping strategies remained relatively stable within personal styles and correlated with the routinely observed styles; however, frequency of negative emotions and conflict tension in crew communications increased. Knowledge of crew communication patterns can help detect early signs of the psychological defense activation and select individualized methods of prompt psychological support.

Making Space for Women: Stories from Trailblazing Women of NASA’s Johnson Space Center ed. by Jennifer M. Ross-Nazzal

Reviewed by: Making Space for Women: Stories from Trailblazing Women of NASA’s Johnson Space Center ed. by Jennifer M. Ross-Nazzal Margaret A. Weitekamp Making Space for Women: Stories from Trailblazing Women of NASA’s Johnson Space Center. Edited by Jennifer M. Ross-Nazzal. (College Station: Texas A&M University Press, 2022. Pp. 443. Illustrations, notes index.) With this excellent compilation of oral history interviews, editor Jennifer Ross-Nazzal, the historian at the Johnson Space Center (JSC), the center for human spaceflight and mission control for the National Aeronautics and Space Administration (NASA), introduces readers to twenty-one women whose hard work and dedication helped build that center’s reputation for excellence. As a scholar, I have frequently searched for oral [End Page 393] history interviews in the deep collection that the JSC’s history office created and maintains. The individual experiences and personal recollections of contemporary actors—and the more than 1,400 oral history interviews compiled by the Johnson Space Center as of the book’s printing—deepen understanding of historical events and enliven their retelling. With this collection, Ross-Nazzal brings a selection of those resources to a broader readership. Ross-Nazzal’s introduction provides a well-researched and carefully footnoted summary of the history of women’s participation as NASA professionals. That progress was uneven, as such changes tend to be. She traces the broad outlines of the history beginning from the 1960s, when a woman behind a desk was assumed to be a secretary even if she was not, to the current day, which includes women in JSC’s leadership positions and an onsite childcare center. Ross-Nazzal self-consciously frames this volume as another possible aid to encourage that cultural shift toward women’s fuller participation in the professional work of spaceflight. Ross-Nazzal opens the volume with two oral history interviews from secretaries and administrative support, a fitting choice because for many years women’s participation at JSC was restricted to such roles. Nonetheless, reading these interviews reminds readers how vital such positions were for NASA’s work. The oral histories in this collection feature mathematicians and engineers, then flight controllers, spacesuit technicians, nurses and scientists, astronauts, trainers, senior management, and center management. Given how much the work at JSC focuses on human spaceflight, Ross-Nazzal makes a deliberate choice to illustrate through the book’s structure how much the work of astronauts is embedded in a network of other equally vital positions. The interview subjects go as far back in JSC’s history as Dee O’Hara, the nurse who worked closely with the original seven Project Mercury astronauts. She started at NASA in 1959, before the agency moved its human (then called “manned”) spaceflight operations to Houston. Peggy Whitson brings the story almost to the present as an astronaut who commanded the International Space Station and served as Chief of the Astronaut Office before retiring in 2018 to work for Axiom, a commercial spaceflight company. Throughout, the themes of mentorship and commitment to the mission illustrate how women gained professional footholds in fields that were not always completely welcoming. Often professional advancement decisions occurred because the right job, at the right level, opened at the right time. Readers should note that the chapters are edited versions of oral history interviews, not third-person accounts. As a result, in some instances there are references to federal government employment (such as pay-grade levels and NASA acronyms) that may not be immediately clear. Making Space for Women would be an excellent addition to history, women’s studies, or STEM (science, technology, engineering, and math) [End Page 394] classes to show students the range of careers that might be open to them thanks to these path-breaking women. Margaret A. Weitekamp Smithsonian’s National Air and Space Museum Copyright © 2022 The Texas State Historical Association

A ROBOTIC FLYING CRANE CONTROLLED BY AN EMBEDDED COMPUTER CLUSTER

The applications of UAVs (Unmanned Aerial Vehicles) are growing up and becoming part of many daily tasks in many organizations. However, as matter of fact, the use of a UAV does not mean the decreasing of operational complexities and, consequently, the costs of perform its tasks. Sometimes this high cost is connected to the dependence of well-trained operators and huge remote control facilities to operate asophisticated UAV's. This paper proposes a robotic flying crane using UAV that can perform its tasks as much independent of human interaction as possible, and with a minimum connection to any mission control facilities. This independence will beachieved by embedding the path mission control into the UAV. As path control is embedded, the UAV will have less connections issues with its control center and will be less dependable of human interaction. To prove this concept all kinematics anddynamics of a light than air vehicle (blimp) is develop; a prototype of an embedded parallel-distributed compute was constructed; and new procedures to resolve navigations and collision evasions issues are proposed. The new evasion procedures were implemented into a simulator and a new parallel / distributed program for optimal path discover was developed to be used into the cluster prototype. Tests of the evasion procedures simulator were satisfactory and speed up of embedded proposed cluster showed better performance of proposed framework.

Enabling Remote Responder Bio-Signal Monitoring in a Cooperative Human-Robot Architecture for Search and Rescue.

The roles of emergency responders are challenging and often physically demanding, so it is essential that their duties are performed safely and effectively. In this article, we address real-time bio-signal sensor monitoring for responders in disaster scenarios. In particular, we propose the integration of a set of health monitoring sensors suitable for detecting stress, anxiety and physical fatigue in an Internet of Cooperative Agents architecture for search and rescue (SAR) missions (SAR-IoCA), which allows remote control and communication between human and robotic agents and the mission control center. With this purpose, we performed proof-of-concept experiments with a bio-signal sensor suite worn by firefighters in two high-fidelity SAR exercises. Moreover, we conducted a survey, distributed to end-users through the Fire Brigade consortium of the Provincial Council of Málaga, in order to analyze the firefighters' opinion about biological signals monitoring while on duty. As a result of this methodology, we propose a wearable sensor suite design with the aim of providing some easy-to-wear integrated-sensor garments, which are suitable for emergency worker activity. The article offers discussion of user acceptance, performance results and learned lessons.

Examining autonomous flight safety systems from a cognitive systems engineering perspective: Challenges, themes, and outlying risks

Flight safety systems (FSS) act as a method to terminate off-nominal rocket launches which threaten public safety. Traditional FSS delegate decision authority to an experienced Missile Flight Control Officer (MFCO) tasked with flight termination decisions, observing multiple points of telemetry data in real time to ensure nominal flight status. This study examines the engineering trade-offs, complexities, and pitfalls introduced by automating flight termination decision-making through autonomous flight safety systems (AFSS). We approach this problem from a cognitive systems engineering perspective, connecting aspects of AFSS to existing literature in human-machine teaming and resilience engineering. Based on information gathered from a series of semi-structured interviews with various subject matter experts (mission controllers, regulators, engineers, amongst others) and existing literature, we outline a list of four assumptions underlying AFSS operations: (1) The system is fully autonomous, (2) An exhaustive flight safety analysis has been performed, (3) The system will be able to respond appropriately to the world, and (4) MFCO expertise can be captured in (or translated to) software. Our findings highlight that, while the benefits of AFSS hold great promise for increasing the viability of commercial space operations, the automation of an irreversible, instantaneous, and complex decision-making task introduces significant challenges and risks. We propose directions for further research to minimize the likelihood of errant, expensive, and dangerous automated flight terminations.

Effects of isolation, crowding, and different psychological countermeasures on crew behavior and performance.

Studies conducted by I. Altman in the 1960-70s revealed the increase in the individual stress level under isolation and confinement. Altman introduced the term "privacy" as a desired level of personal space that humans need to feel psychologically comfortable. The author also mentioned the dynamic process of boundary regulation that can be accompanied by the increase in conflict tension in the confined groups. In our study with short-term chamber isolation ESKIS, we analyzed behavior, crew interactions, and psychological state of a mixed-gender crew with none or minimal previous isolation experience (4 males and 2 females) who spent 14 days in a small chamber of 50m3. The study confirmed that the pre-isolation period was particularly stressful for the subjects who felt also significant anxiety during the first days of isolation. Also, some mood and sleep disturbances were detected under isolation and crowding. Psychological stress made the crew more cohesive; they demonstrated the increase in common values. Extraverted subjects who could obtain social support from their partners and Mission Control's duty teams were less interested in psychological support via VR.

The Cancer Moonshot Enters a New Phase.

The Obama Administration launched the Cancer Moonshot in 2016 to accelerate aspects of cancer research, with then-Vice President Biden in charge of "mission control." With the signing into law of the 21st Century Cures Act, the U.S. Congress authorized $ 1.8 billion in funding for the Cancer Moonshot over seven years starting in 2017. The National Cancer Institute (NCI) has invested those funds in more than 240 research projects and 70 programs in research priority areas including improving the understanding of cancer, encouraging collaboration and data sharing, and addressing cancer disparities [1].

Understanding and characterizing speaker roles within naturalistic task-based communications: The fearless steps APOLLO-11 corpus

Naturalistic team based speech communications requires specific protocols/procedures to be followed to allow for effective task completion for distributed team members. NASA Apollo-11 was the first manned space mission to successfully bring astronauts to the moon and return them safely. Mission specialists roles within NASA Mission Control (MOCR) are complex and reflected in their communications. In this study, we perform speaker clustering to identify speech segments uttered by the same speaker from recently recovered Fearless Steps APOLLO corpus (CRSS-UTDallas). We propose a pretrained network to obtain speaker embeddings and use a framework that builds on these learned embeddings which achieves a clustering accuracy of 73.4%. We also track/tag key speakers-of-interest across three critical mission phases and analyze speaker roles based on speech duration. NASA communication protocols dictate that information be communicated in a concise manner. In automated communication analysis, individuals higher in trait dominance generally speak more and gain more control over group processes. Hence, speaker duration of primary- versus -secondary speaker and speaker turns are metrics used to determine speaker role. This analysis provides greater understanding of communications protocol and serves as a lasting tribute to the «Heroes Behind the Heroes of Apollo» as well as preserve “words spoken in space.”

Detecting Discontinuities From In Situ Space Measurements: Method and FPGA Implementation

AbstractThe analysis in real time of space data variability is essential for scientists and space mission controllers. Automated tools designed to extract key descriptors of variability are needed and solutions to adapt such algorithms for on‐board computers are rare. This paper describes the design of an automated system for detecting directional discontinuities of a physical quantity and its implementation in Field‐Programmable Gate Array (FPGA). The system is currently adapted for solar wind or terrestrial magnetosheath magnetic field directional discontinuities, that is, sharp changes of the magnetic field directionality. Our detection algorithm uses analysis windows of adjustable width and averaging procedures in order to reduce the effects of random fluctuations. A sliding‐window approach is designed for continuous monitoring and detection of magnetic directional discontinuities. A software implementation of the algorithm was tested using in‐situ magnetic field measurements, and emphasized improvements of performance when using analysis windows of adjustable width. The FPGA implementation of the detection algorithm is built on DILIGENT Nexys 4 DDR featuring a commercial Xilinx Artix‐7 device and is designed to be ported to space qualified infrastructure. The FPGA system was tested with synthetic and laboratory signals, and provides results in very good agreement with the software implementation. The FPGA system provides an efficient real‐time monitoring solution using minimal computational and energy resources, and reducing the main on‐board computer utilization.

Effect of Explanations in AI-Assisted Anomaly Treatment for Human Spaceflight Missions

Artificial Intelligence (AI) agents have the potential to play a critical role in human spaceflight by being the first point of contact for astronauts during emergencies in a long duration spaceflight mission, when communication delays with the Mission Control Crew (MCC) become longer and more frequent. Sharing some of tasks done by the MCC with an on-board AI agent that can provide assistance with treating in-flight anomalies gives the crew more autonomy and allows them to respond faster and more safely to emergencies, or focus on other critical aspects of their mission. For this technology to succeed in this role, providing accurate diagnoses for the anomalies encountered is obviously important. However, providing explanations for those recommendations may also be a critical factor to help establish trust and increase the likelihood of the crew actually following the agent’s recommendations. This paper evaluates the effects of explanations on crew performance, trust in automation, mental workload, and situational awareness in the context of anomaly resolution tasks. We conduct a study where subjects subjects work with the AI agent on various simulated anomaly scenarios. They are provided by the agent with a diagnosis and recommendation with no explanations in one session and with explanations for its diagnosis in the other session. We measure the effects of the explanations on Trust in Automation, Situational Awareness, Performance, and Workload. We discuss our findings and provide design recommendations for AI agents in the context of anomaly treatment in Long Duration Exploration Missions (LDEM).

Initial development of tandem wing UAV aerodynamic configuration

PurposeUnmanned aerial vehicles (UAV) with remote and/or automated flight and mission controls have replaced airplanes with pilots in many important roles. This study aims to deal with computational fluid dynamics (CFD) analysis and development of the aerodynamic configuration of a multi-purpose UAV for low and medium altitudes. The main aerodynamic requirement was the application of the tandem wing (TW) concept, where both wings generate a positive lift and act as primary lifting devices.Design/methodology/approachInitial design analyses of the UAV’s aerodynamic configuration were performed using ANSYS Fluent. In previous work in Fluent, the authors established a calculation model that has been verified by experiments and, with minor adjustments, could be applied for subsonic, transonic and supersonic flow analyses.FindingsThe design evolved through eight development configurations, where the latest V8 satisfied all the posted longitudinal aerodynamic requirements. Both wings generate a substantial amount of positive lift, whereas the initial stall occurs first on the front wing, generating a natural nose-down stall recovery tendency. In the cruising flight regime, this configuration has the desired range of longitudinal static stability and its centre of pressure is in close proximity to the centre of gravity.Practical implicationsThe intermediate development version V8 with proper longitudinal aerodynamic characteristics presents a good starting point for future development steps that will involve the optimization of lateral-directional aerodynamics.Originality/valueUsing contemporary CFD tools, a novel and original TW aerodynamic configuration have evolved within eight development stages, not being based on or derived from any existing designs.

Finite-Time Prescribed Performance Control for Space Circumnavigation Mission With Input Constraints and Measurement Uncertainties

This article presents a 6-DOF attitude-orbit synchronous control problem for the space circumnavigation (SCN) mission with parameter uncertainties, time-varying uncertainties, and input constraints. In particular, from the perspective of engineering application, time-varying measurement uncertainties are taken into account of the 6-DOF attitude–orbit coupling kinematics and dynamics, and the analytical solution of the desired attitude is derived based on the measured relative orbit information with measurement uncertainties. To drive the active spacecraft approach to the faulty target safely, a time-varying exponential prescribed convergence boundary is introduced into the sliding surface. A finite-time disturbance observer is involved in equivalent tracking errors for compensating the mismatched uncertainties. In addition, an auxiliary system is designed to overcome the instability danger caused by input constraints. The stability of the controlled system is discussed in the nonautonomous finite-time stable framework, which is proved via Lyapunov analysis that the attitude-orbit tracking errors converge to the equilibrium within finite time. The simulation experiment with mismatched uncertainties and prescribed constraints shows the superiority of the designed control scheme.

The Cruel Optimism of Anthropocene Technologies: Suspicion and Fascination of Technology in Okja, What Happened to Monday, and Geostorm

The Cruel Optimism of Anthropocene Technologies: Suspicion and Fascination of Technology in <i>Okja</i>, <i>What Happened to Monday</i>, and <i>Geostorm</i>

Similar Loss of Executive Function Performance after Exposure to Low (10 cGy) Doses of Single (4He) Ions and the Multi-Ion GCRSim Beam.

While astronauts are trained to deal with multiple issues that they are likely to encounter during a mission, it is likely that some problems will arise that astronauts have no direct experience in resolving. During International Space Station (ISS) missions, astronauts can rely on Mission Control to help resolve complex problems, however during the long-duration space missions planned to the Moon and Mars, astronauts will have to act more autonomously, thus the ability of astronauts to conduct executive function will be critical for problem solving during deep space missions. Several studies have shown that exposure to space radiation results in decreased executive function performance. However, to date these studies have used single ions, whereas there is a complex mixture of ion species and energies within the space-radiation spectrum that astronauts will be exposed to. Thus, there is some concern that the neurocognitive impairments reported from single ion studies will not be representative of the severity, frequency or nature of cognitive deficits that arise following exposure to more complex space-radiation spectra. The current study has determined the relative impact that isodoses of He ions or the simplified 6-ion-galactic cosmic ray simulation (GCRSim) beams had on the performance of male Wistar rats in executive function tasks, attentional set shifting (ATSET) task and unconstrained cognitive flexibility (UCFlex). Exposure to 10 cGy GCRSim induced performance deficits in the simple discrimination (SD) stage of the ATSET task, which appears to be universally impacted by all space-radiation ions studied to date. The magnitude of the SD performance decrements in the GCRSim-irradiated rats were comparable to those observed in He-irradiated rats. Importantly, space-radiation exposure does not appear to decrease the ability of rats to identify the key cues in the ATSET task, but increased the time/number of iterations required to successfully find the solution. Practice effect (PE) analysis (comparing prescreen to the postirradiation SD performance) revealed that while the sham-treated rats completed the second ATSET task in 30% less time than they did the prescreen ATSET test (despite the perceptual domain of the relevant (rewarded) cue being changed), the space-radiation-exposed rats took 50% longer to do so. The space-radiation-induced delay in problem solving was not confined to the ATSET task, but was also observed when rats were screened for UCFlex performance. Should similar changes occur in astronauts, these data raise the possibility that space-radiation exposure would reduce in-flight improvement in performance in repetitive tasks (PE) and may lead to a reduced ability to utilize transitive inference from "similar" problems to solve issues that have not been previously encountered.

Similar Loss of Executive Function Performance after Exposure to Low (10 cGy) Doses of Single (4He) Ions and the Multi-Ion GCRSim Beam.

While astronauts are trained to deal with multiple issues that they are likely to encounter during a mission, it is likely that some problems will arise that astronauts have no direct experience in resolving. During International Space Station (ISS) missions, astronauts can rely on Mission Control to help resolve complex problems, however during the long-duration space missions planned to the Moon and Mars, astronauts will have to act more autonomously, thus the ability of astronauts to conduct executive function will be critical for problem solving during deep space missions. Several studies have shown that exposure to space radiation results in decreased executive function performance. However, to date these studies have used single ions, whereas there is a complex mixture of ion species and energies within the space-radiation spectrum that astronauts will be exposed to. Thus, there is some concern that the neurocognitive impairments reported from single ion studies will not be representative of the severity, frequency or nature of cognitive deficits that arise following exposure to more complex space-radiation spectra. The current study has determined the relative impact that isodoses of He ions or the simplified 6-ion-galactic cosmic ray simulation (GCRSim) beams had on the performance of male Wistar rats in executive function tasks, attentional set shifting (ATSET) task and unconstrained cognitive flexibility (UCFlex). Exposure to 10 cGy GCRSim induced performance deficits in the simple discrimination (SD) stage of the ATSET task, which appears to be universally impacted by all space-radiation ions studied to date. The magnitude of the SD performance decrements in the GCRSim-irradiated rats were comparable to those observed in He-irradiated rats. Importantly, space-radiation exposure does not appear to decrease the ability of rats to identify the key cues in the ATSET task, but increased the time/number of iterations required to successfully find the solution. Practice effect (PE) analysis (comparing prescreen to the postirradiation SD performance) revealed that while the sham-treated rats completed the second ATSET task in 30% less time than they did the prescreen ATSET test (despite the perceptual domain of the relevant (rewarded) cue being changed), the space-radiation-exposed rats took 50% longer to do so. The space-radiation-induced delay in problem solving was not confined to the ATSET task, but was also observed when rats were screened for UCFlex performance. Should similar changes occur in astronauts, these data raise the possibility that space-radiation exposure would reduce in-flight improvement in performance in repetitive tasks (PE) and may lead to a reduced ability to utilize transitive inference from "similar" problems to solve issues that have not been previously encountered.

Constrained adaptive fuzzy super-twisting control for space circumnavigation mission with input constraints and rough dynamics information

The 6-DOF attitude-orbit fast synchronous control problem in the space circumnavigation mission is investigated in this paper with dynamics coupling, uncertainties and disturbances, input constraints, and rough dynamical information feedbacks. The orbital-information-based desired angular acceleration information is dynamically compensated via a set of hierarchical fuzzy systems to avoid the derivation operation of orbital states amplifying measurement noise. Since the adaptive laws for updating fuzzy weights are developed based on hyperbolic tangent function, estimation results are updated slowly, even if the initial tracking errors are large. A novel nonsingular practical terminal sliding-mode (PTSM) reduced-order system is proposed for drive tracking errors fast converge with high precision. Benefiting from the absence of information coupling in the derivative of the PTSM function, an observation-based super-twisting algorithm (STA) is employed to establish the PTSM manifold with weakened chattering. Adaptive laws estimate the maximum uncertainty, and an auxiliary system compensates for the input constraints. Simulation results verify the effectiveness of the proposed control scheme.