Activities Of Astronauts Research Articles

Skin-inspired multimodal tactile sensor aiming at smart space extravehicular multi-finger operations

Tactile sensing of skin shapes the interactions between hand and the surrounding world, owing to the remarkable natural sensory system. But for astronauts, tactile feedback cannot be obtained biologically due to the very thick protective gloves, which seriously hinders the flexibility of the extravehicular activity. In this work, inspired by human skin, we develop a biomimetic multi-layer tactile sensor (BMLTS) that can work like the fast adaptive and slow adaptive receptors of fingertip to achieve the multimodal tactile perception based on the fusion of thermosensitive, piezoelectric, triboelectric and piezoresistive materials. Based on the BMLTS, the tactile perception for temperature, surface roughness discrimination and smart object grasping is successfully achieved, which fully simulates the basic tactile perceptions in typical extravehicular operations. Furthermore, by the combination of BMLTS and deep learning, a biomimetic intelligent perception system (BIPS) that can make decisions to the tactile signal just like human brain is constructed, which can provide real-time tactile information for astronauts. Intelligent real-time object material identification, writing and recording are conducted using BIPS, reaching the recognition accuracy rate higher than 95%. This work lays the foundation for the systematization and integration of tactile sensors, and paves the way for the development of dexterous tactile perception for smart extravehicular activities of astronauts.

Monte Carlo analysis of dosimetric issues in space exploration

The Radiation protection is of paramount importance in the planning of human exploration activities in space. The related risks must be considered with respect to two aspects: devising a proper shielding and providing answers to the requirement of an effective dosimetry evaluation in astronaut's activities. Both aspects have been considered using the Monte Carlo (MC) code MCNP 6.2 as the reference tool. As case study an application devised for the National Aeronautics and Space Administration (NASA) Artemis program has been chosen. The project aims to establish a sustainable human presence on the Moon, envisioning the realization of an outpost that will serve as a steppingstone for space exploration endeavors. A Class III shelter, in situ resource utilization (ISRU) built habitat for the Moon, has been designed through computational methods and topology optimization techniques, and analyzed in terms of radiation shielding performances and the strictly related structural behavior. The outpost must be able to withstand temperature variations, micrometeorite impacts, and the absence of a substantial atmosphere. Any solution studied to respect the constraints must devise robust and innovative materials and techniques to create habitats that have as goal the shielding from the Galactic Cosmic Rays (GCR) and from the solar flares to provide a safe and habitable environment at the time scales scheduled for the missions. Moreover, the outpost design must incorporate strategies for extracting and utilizing local resources. Overcoming such challenges will pave the way for the establishment of a sustainable human presence on the Moon and serve as a crucial leap for future space exploration missions.

Shielding factors for a fission-powered mars exploration rover

Background: With the advances in compact fission power systems and Stirling converters, the efficiency and portability of electrical energy production systems has increased substantially thanks to NASA’s Kilopower project. These 1-10 kWe-class reactors are compact enough to be transportable by pressurized rovers, allowing an extended human reach across the surface of Mars to produce scientific data at a rate that greatly surpasses the rate of robotic rover data collection. If rovers were to harness fission power while mobile, it is possible for near-limitless range. This capability could allow one crew on Mars for under a “Conjunction” class mission as outlined in NASA’s Mars Design Reference Architecture (DRA) 5.0 to visit many geological sites of interest instead of requiring additional landings to explore distant features of the Martian surface. This study explored the parameters that affected the mass of the shielding required to protect the crew against a fission reactor embedded in the chassis of a pressurized rover. Methods: An analytical approach was devised to estimate the required mass of a hypothetical solid tungsten shield under various conditions. Results: Power levels below 3.4 kWe were found to be impractical for rover applications. Between 3.4 kWe and 10 kWe would be able to recharge the rover without returning to base camp. The increase in shielding mass from a 3.4 kWe reactor and a 10 kWe reactor was 6%. The reduction between a 10 kWe reactor at 3 m and 6 m was 7%. Varying the shield thickness in accordance with astronaut activities resulted in a 19% reduction. Powering the reactor off before exiting the vehicle resulted in an additional 65% reduction. Conclusions: Knowledge of the crew activities and locations had the greatest impact on the required shielding mass and the mission activities should be well-understood before finalizing a shield design.

EFFECT OF SIMULATED SPACE CONDITIONS ON FUNCTIONAL CONNECTIVITY

Long duration spaceflight missions can affect the cognitive and behavioral activities of astronauts due to changes in gravity. The microgravity significantly impacts the central nervous system physiology which causes the degradation in the performance and lead to potential risk in the space exploration. The aim of this study was to evaluate functional connectivity at simulated space conditions using an unloading harness system to mimic the body-weight distribution related to Earth, Mars, and International Space Station. A unity model with six directional arrows to imagine six different motor imagery tasks associated with arms and legs were designed for the Oculus Rift S virtual reality headset for testing. An Electroencephalogram (EEG) and functional near infrared spectroscopy (fNIRS) signals were recorded from 10 participants in the distributed weight conditions related to Earth, Mars, and International Space station using the g.Nautilus fNIRS system at sampling rate of 500 Hz. The magnitude squared coherence were estimated from left vs right hemisphere of the brain that represents functional connectivity. The EEG coherence was the higher which shows the strong functional connectivity and fNIRS coherence was lower shows weak functional connectivity between left vs right hemisphere of the brain, during all the tasks and trials irrespective of the simulated space conditions. Further analysis of functional connectivity needed between the intra-regions of the brain.

Long-duration isolation experiments in preparation of interplanetary missions: Psychological support of international crews

The current development of international cooperation, assimilation and integration of representatives of different ethnic groups has led to the urgent need to take this factor into account in the planning, organization and implementation of complex scientific and technological projects, such as space exploration missions (Moon or Mars missions). In this regard, it becomes obvious that crew training and in-flight activities of astronauts cannot be planned without considering intercultural relations, including relevant psychological support of international crews, playing a key role for the success of such space missions. The efficiency of the entire range of activities related to space activities in general depends directly on the ability to build cross-cultural relationships between all stakeholders. The main tool of achieving mutual understanding in any kind of activity in general and the work of astronauts in particular is communication. Communication among the crew of astronauts and with ground control is strongly impacted by their cultural background and in long-duration space missions this impact is strongly aggravated.This paper presents a quantitative complex study of the impact of cultural background of members of an international crew on their information and communication needs with the outside world during long-duration isolation and autonomy during the Mars-500 project. In the course of the study a new approach to psychological support of an international crew in ground-based isolation studies was developed and implemented, considering culturally influenced information and communication needs of the international crew members. It was demonstrated that it is necessary to combine the principle of parity of information support in a long-duration autonomous mission of an international crew with the principle of individualization of psychological support, based on the cultural identity and psycho-physiological condition of the crew members. The results of the study have confirmed the efficiency of this new approach and represent a valuable input for the further development of psychological support of international crews during long-duration isolation / space missions.

Exercises and Skin Physiology During International Space Station Expeditions

BACKGROUND: The first skin physiological pilot experiment (SkinA) on a single astronaut showed a deterioration of the skin. In a follow-up experiment (SkinB) we showed that skin physiological parameters improved on average. However, it is well known that sports have positive effects on the skin, that astronauts prefer special sports devices, and do sports with different intensity. The aim of this study was to analyze the different sports activities of SkinB astronauts and to find out whether they have an influence on the skin physiological parameters.METHODS: The cumulative distance covered on the treadmill and on the cycle ergometer as well as the repetition of arm-related exercises have been calculated and possible correlation between sports activities and skin physiological parameters have been analyzed.RESULTS: The average distance covered for all six astronauts per day is 1364 AU on the treadmill T2, and 11,077 AU on the cycle ergometer CEVIS. In addition, the astronauts performed an average of about 73 repetitions of all arm-related exercises daily. Here, we were able to show very well how differently the astronauts on the ISS train. In addition, a decreasing trend in skin volume can be observed in astronauts with increasing activity on the bicycle and more repetitions on arm-related exercises.CONCLUSION: Increased activity on the cycle ergometer and increased arm-related exercises have a medium negative impact on the parameter skin volume and thus reflects more fluid content in the skin. No correlations between sports activities and skin moisture/skin barrier function could be found.Braun N, Hunsdieck B, Theek C, Ickstadt K, Heinrich U. Exercises and skin physiology during International Space Station expeditions. Aerosp Med Hum Perform. 2021; 92(3):160166.

Lunar Dust: Properties and Potential Hazards

The surface of the Moon, like that of any airless body in the Solar System, constantly experiences micrometeorite bombardment as well as the influence of solar radiation, solar wind, and other factors of outer space. As a result of the impacts of high-velocity micrometeorites over billions of years, the lunar surface silicate basis crumbles, turning into particles with a wide size distribution. Considering the explosive nature of their origin, these particles are characterized by an extremely irregular shape with sharp edges or conglomerates sintered at high temperatures or almost spherical droplets. On the illuminated side of the Moon, solar radiation, especially the ultraviolet part of its spectrum, and solar wind streams interact with the upper regolith layer, charging the regolith surface. The photoelectrons generated above the surface create, together with the charged regolith surface, a near-surface double layer. The electric field generated in this layer, as well as the particle charge fluctuations on the surface, create conditions under which electric forces may exceed the gravitational force and the van der Waals force of adhesion. As a result, micron- and submicron-sized regolith particles become capable of detaching from the surface and levitating above it. These dynamic processes cause the transport of dust particles above the lunar surface and the scattering of sunlight on these particles. Glows of this kind were observed over the lunar surface by television systems of American and Soviet landing vehicles in the early stages of lunar exploration. American astronauts who landed on the lunar surface during the Apollo program also discovered manifestations of lunar dust. It turns out that dust particles levitating over the regolith surface due to natural processes and those took off the surface due to anthropogenic factors cause many technological problems that compromise the performance of landing vehicles and their systems, hamper astronaut activity on the lunar surface, and are detrimental to their health. Based on the results of these missions, it is concluded that micron- and submicron-sized dust particles, levitating above the surface, pose a major, barely surmountable obstacle in further research and exploration of the Moon. Since then, studies of physical processes associated with the behavior of lunar dust, manifestations of its aggressive properties (toxicity), and ways to reduce the harmful effects of dust on engineering systems and on humans have become topical in theoretical and experimental research. In this review, the results of the past half century of studies on the behavior of dust particles serve as a basis to discuss the formation of the lunar regolith and the Moon’s near-surface plasma–dust exosphere under the influence of outer space factors. The causes and conditions underling the behavior of dust particles are examined as well as implications of these processes, the influence of anthropogenic factors, and possible hazards to spacecraft and engineering systems during the implementation of the currently planned programs of lunar research and exploration. The main unsolved problems are listed in studying the behavior of the dust component of the lunar regolith; ways to address the problematic issues are discussed.

Conceptual Design of Spacesuit Hard Hip Joint

Spacesuit hip joint plays an important role on astronaut activities, such as planetary walking and surveying. This paper proposes a conceptual design of hard hip joint in consideration of the coupling effect of spacesuit hip joint and astronaut thigh. Firstly, lower extremity activities are introduced to illustrate the mobility of hard hip joint, such as walking, kneeing, and abduction. A conceptual design of hard hip joint is explained in detail, including geometric structure, components, design parameters, and mechanism models. Secondly, a 3-linkage coupling mechanism model is built up by synthesizing that conceptual design of hard hip joint. An equiangular dual-perpendicular representation method is brought out to parameterize that mechanism model of hard hip joint. Particularly, four geometric constraints are, respectively, given out to avoid impact between the hip joint and the thigh and to ensure the continuity of thigh motion. Finally, motion equations of hip joint parts are established by using coordinate transformation and vector representation. A case study is conducted to verify the correctness of the proposed representation method and that coupling mechanism model.

Circadian regulation of physiology: Relevance for space medicine

The circadian clock is an endogenous time-generating system accountable for the synchrony between the internal and the geophysical time. In recent years, chronobiology research has demonstrated that the circadian regulation of numerous molecular and cellular processes leads to a temporal control of physiology and behaviour. These findings alert to the negative impact on health caused by a disrupted internal timing.In this review we address the relation between atypical external factors in long-term space flights (or other extreme environments) and circadian clock misalignment, stressing the need of establishing preventive measures to minimize the effect on human health and performance. For this purpose, daily activities of astronauts (or humans living in extreme environments) could be planned according to the individual’s internal biological time, which can be achieved through the synergy between the molecular characterization of the circadian clock and computational predictive mathematical models.

Astronaut Visual Tracking of Flying Assistant Robot in Space Station Based on Deep Learning and Probabilistic Model

Real-time astronaut visual tracking is the most important prerequisite for flying assistant robot to follow and assist the served astronaut in the space station. In this paper, an astronaut visual tracking algorithm which is based on deep learning and probabilistic model is proposed. Fine-tuned with feature extraction layers’ parameters being initialized by ready-made model, an improved SSD (Single Shot Multibox Detector) network was proposed for robust astronaut detection in color image. Associating the detection results with synchronized depth image measured by RGB-D camera, a probabilistic model is presented to ensure accurate and consecutive tracking of the certain served astronaut. The algorithm runs 10 fps at Jetson TX2, and it was extensively validated by several datasets which contain most instances of astronaut activities. The experimental results indicate that our proposed algorithm achieves not only robust tracking of the specified person with diverse postures or dressings but also effective occlusion detection for avoiding mistaken tracking.

Brain Quantitative MRI Metrics in Astronauts as a Unique Professional Group.

As part of its technological sophistication, the International Space Station (ISS) Program operates a robust medical surveillance schedule for its rotating 6-person crew to control the known health risks and to address knowledge gaps related to human health in space flight environment. Recent evidence on visual impairment in a subset of ISS crew has renewed the interest in the effects of long-duration space flight on the central nervous system (CNS). Through retrospective analysis in a sample of 10 healthy astronauts, we demonstrate the utility of multimodal quantitative magnetic resonance imaging (qMRI) with diffusion tensor imaging (DTI)-based customized brain templates to examine the structural attributes of various CNS compartments in this occupational group. The study included 10 healthy astronauts (45-55 years). All subjects had previous space flights with the median duration of 110 days. Multimodal quantitative structural imaging modalities performed and used in analyses. A host of CNS features are presented, which are largely commensurate with the available normative data. Remarkably, some of our findings demonstrate statistically significant positive features suggestive of structural neuroplasticity conceivably associated with the professional activities of astronauts, and compensatory neurogenesis that counterweighs the expected normative volume loss with age. The novelty of this exploratory report is in the demonstration of a qMRI toolset as a potential capability for characterization and surveillance of unique professional groups, and for future prospective examinations of the effects of various long-term exposures on CNS.

A Context-based Approach to Robot-human Interaction

CARIL (Context-Augmented Robotic Interaction Layer) is a human-robot interaction system that leverages cognitive representations of shared context as a basis for a fundamentally new approach to human-robotic interaction. CARIL gives a robot a human-like representation of context and an ability to reason about context in order to adapt its behavior to that of the humans around it. This capability is “action compliance.” A prototype CARIL implementation focuses on a fundamental form of action compliance called non-interference -- “not being underfoot or in a human's way”. Non-interference is key for the safety of human-co-workers, and is also foundational to more complex interactive and teamwork skills. CARIL is tested via simulation in a space-exploration use-case. The live CARIL prototype directs a single simulated robot in a simulated space station where four simulated astronauts are engaging in a variety of tightly-scheduled work activities. The robot is scheduled to perform background tasks away from the astronauts, but must quickly adapt and not be underfoot as astronaut activities diverge from plan and encroach on the robot's space. The robot, driven by CARIL, demonstrates non-interference action compliance in three benchmarks situations, demonstrating the viability of the CARIL technology and concept.

Effects of rocket exhaust on lunar soil reflectance properties

High-resolution images of the Surveyor, Luna, and Apollo landing sites obtained by the Lunar Reconnaissance Orbiter Camera (LROC) Narrow Angle Camera (NAC) show regions around the landers where reflectivity of the surface was modified. We interpret the change in reflectance properties of these regions mainly as disturbance of the regolith by rocket exhaust during descent of the spacecraft and we refer to these areas herein as “blast zones” (BZs). The BZs consist of an area of lower reflectance (LR-BZ) compared to the surroundings that extends up to a few meters out from the landers, as well as a broader halo of higher reflectance (HR-BZ) that extends tens to hundreds of meters away from the landers. When approximated as an ellipse, the average Apollo BZ area is ∼29,000m2 (∼175±60m by 200±27m) which is 10× larger than the average Luna BZ, and over 100× larger than the average Surveyor BZ. The LR-BZs are most evident at the Apollo sites, especially where astronaut activity disturbed the soil, leading to a 15–30% (relative to background undisturbed areas) reduction in reflectance at ∼30° phase angle. The LR-BZs at the Surveyor and Luna sites are less evident and are unresolvable with NAC images. The average reflectance in the HR-BZs as determined for 30° phase angle is 3–12% higher than in the undisturbed surrounding areas; this magnitude is the same, within uncertainty, for all sites, indicating a common process or combination of processes causing differences in reflectance properties of the regolith. Phase-ratio images and photometric data collected over a range of illumination geometries show that a greater separation in reflectance occurs between the HR-BZs and undisturbed areas at phase angles between 0° and 70° and indicates that the HR-BZs are less backscattering than undisturbed areas. The LR-BZs are affected by macroscopic disruption of the surface and astronaut activity (at the Apollo sites). For the HR-BZ areas, reflectance has likely been affected by scouring from particles entrained by exhaust gases with low-angle trajectories. Regolith particle interactions with surface soil within HR-BZs may destroy fine-scale surface structure (e.g., “fairy-castle”) and decrease macroscopic roughness, contributing to a decrease in backscattering character within the HR-BZs and an increase in backscattering character within the LR-BZs. Redistribution of fine particles from the LR-BZ to the HR-BZ may have also contributed to the changed reflectance. Photometric modeling is consistent with one or a combination of these processes.

Digital Vision Systems and Wearable Computing Technologies for Assisting Astronauts During Intra- and Extra-Vehicular Activity

This paper examines the application of humanistic intelligence design paradigms and wearable computing technologies to astronaut daily activities and future spacesuit designs. A specific focus is on display technologies providing an augmented and mediated reality. These wearable computer technologies (WCT) are discussed in the context of an astronaut's activities inside a spacecraft, during extra-vehicular activities, and on the surfaces of celestial bodies. Options for wearable computer displays with augmented reality interfaces are presented and recent patents in the field are included. Examples showing the astronaut's using an augmented and mediated reality display integrated into a headband during repair activities onboard the International Space Station, or a spacesuit visor during planetary surface exploration, are provided. The advantages of other WCT, such as sensors for brainwave and tactile feedback for assisting in awareness and spatial orientation, are also discussed. The scope of this paper is intended to attract interest from multiple disciplines pertaining to the nature of space projects in general. Furthermore, the application of the humanistic intelligence design principles provides a framework to assist current experts in improving WCT designs for astronauts in the future. Keywords: Humanistic intelligence, wearable computer, astronauts, spacesuit, vision systems.

2P1-M05 宇宙飛行士支援・代替ロボットMorphable Beam Robotのコンセプトと部分試作機の開発(【宇宙工学部門】宇宙工学とロボティクス・メカトロニクス)

In order to exceed the working and moving capabilities of existing robots for supporting and substituting of astronaut's activities, this paper shows the new robot concept. The robot body is consisted of the hyper redundant and shape memorable structure, Morphable Beam. It can work and move extensive fields, and it can be in the compact-sized storage. It also has the collision tolerance and the safety for astronauts or space stations. This paper also shows the development of the beam shaping prototype robot and the test data of the prototype robot. It was developed to show the feasibility and appropriateness of the concept. Authors confirmed the beam bending and appropriateness of the robot.

An Ambulatory Biomechanical Data Collection System for Use in Space: Design and Validation

Loss in bone mineral density and muscle strength in astronauts following long-duration spaceflight have been well documented, but the altered force and movement environments in microgravity which may contribute to these changes have not been well characterized. This paper describes the instrumentation, software, and data collection procedures developed for the "Foot" experiment that was conducted on the International Space Station (ISS) to provide insight into the biomechanics of daily activity in a microgravity environment. The instrumentation used for data collection included the Ambulatory Data Acquisition System (ADAS), ADAS electromyography (EMG) modules, the Joint Excursion System, and the Total Force-Foot Ground interface system, which were all integrated into a specially designed Lower Extremity Monitoring Suit. There were 14 total channels of data that were collected at sampling rates between 8 Hz and 1024 Hz, including 7 channels of EMG, 4 channels of joint angle data, 2 channels of in-shoe ground reaction force, and a marker channel for event recording. Data were typically collected for between 6.5 and 11.8 h of activity during 4 d on Earth and 4-7 d in flight. Exemplar data sets collected preflight on astronauts in 1 g to validate the instrumentation are presented. We conclude that the system provides valid and useful biomechanical information on long-term activity. The analysis of data collected on-orbit using the system described here will be presented in a series of future papers characterizing the biomechanics of astronaut activity during complete working days on the Earth and on the ISS.

A Visualization Framework for Bounding Physical Activities — Towards a Quantification of Gibsonian-Based Fields

In a human-robot communications problem in which a mobile robot and an astronaut are required to work together to maintain network communication, it is possible for the mobile robot and the astronaut to have multiple courses of actions to restore communications if it becomes disrupted. To effectively accomplish a team's mission, a human supervisor responsible for monitoring and supervising the terrestrial activities of mobile robots and astronauts in this domain needs useful decision aiding tools in order to identify productive courses of action. Motivated by this, we propose a visualization framework based on Gibsonian-based fields for representing a mobile robot and an astronaut's possible action strategies to maintain their network communication in a continuous and dynamic environment and for graphically representing bounds on actualized action strategies of the robot and the astronaut based on their possible action strategies. The authors submit that it is not sufficient simply to calculate all the possible actions of the mobile robot and the astronaut. It is equally important to provide interfaces that reveal affordances in the domain in a manner that delineates the length and breadth of action opportunities and human perceptual and physical capabilities. We present a simple conceptualization of the problem of robot-astronaut communication in order to develop a framework for analysis that can be generalized to multiple robots and astronauts communicating to meet multiple objectives.

415 三次元多腕型宇宙ロボットの運動解析(ロボット,OS-14:マルチボディダイナミクス)

In recent years, the space robot which does various works with the manipulator has been studied actively, in order to cope with various problems in astronaut's activities outboard. Unfortunately, the motion of a space manipulator causes disturbance to the spacecraft, because angular momentum is conserved in space. In this paper, based on the Kane's dynamical equation and an approach of multi-body dynamics, motion analysis is done in consideration of conservation law of angular velocity to built an equation of motion of the space robot in three-dimension, which is a first-order nonholonomic system. We show that our proposed algorithm is applicable to any tree-structured space robot by carrying out simulation for a cat robot.

多腕型三次元宇宙ロボットの運動解析(OS.8 動解析の新展開-マルチボディ,モード解析,最適設計-)

In recent years, the space robot which does various work by the manipulator is researched actively, in order to cope with various problems in an astronaut's activities outboard. Unfortunately, the motion of a space manipulator causes disturbance to the spacecraft, because angular momentum is conserved in space. Since it is impossible to integrate the velocity constraint with respect to time, the system is considered to be a first-order nonholonomic system. In this paper, based on the idea of a multi-body dynamics, motion analysis is done in consideration of conservation laws of angular momentum to build an equation of motion in three dimensions.

Multinational and ethical issues in manned-space strategy

This paper discusses alternative approaches to communication and dispute resolution pertinent to a variety of perspectives on manned-space strategy. Since contemporary astronaut activities are both national and multinational, and increasingly involve different sectors, cultures, disciplines and specialists, there is reason to reflect on the potential use of astronauts in advisory roles to entities and groups of individuals.