Space Operations Research Articles

Adaptive quantum accelerated imaging for space domain awareness

The growth in space activity has increased the need for Space Domain Awareness (SDA) to ensure safe space operations. Imaging and detecting space targets is, however, challenging due to their dim appearance, small angular size/separation, dense distribution, and atmospheric turbulence. These challenges render space targets in ground-based imaging observations as point-like objects in the sub-Rayleigh regime, with extreme brightness contrast but a low photon budget. Here, we propose to use the recently developed quantum-accelerated imaging (QAI) for the SDA challenge. We mainly focus on three SDA challenges (1) minimal a priori assumptions (2) many-object problem (3) extreme brightness ratio. We also present results on source estimation and localization in the presence of atmospheric turbulence. QAI shows significantly improved estimation in position, brightness, and number of targets for all SDA challenges. In particular, we demonstrate up to 2.5 times better performance in source detection than highly optimized direct imaging in extreme scenarios like stars with a 1000 times brightness ratio. With over 10 000 simulations, we verify the increased resolution of our approach compared to conventional state-of-the-art direct imaging paving the way towards quantum optics approaches for SDA.

A systems approach for characterizing human deep space mission anomaly response capabilities and functional constraints

Human exploration of Mars and beyond will demand unprecedented levels of onboard self-sufficiency due to the exceedingly far distances from Earth and lengthy mission durations. This paradigm shift will require the development of novel anomaly response architectures to protect future crews adequately from anomalies and failures. In this paper we outline and demonstrate a process to identify and evaluate key factors that affect the anomaly response process for deep space operations. It builds on established frameworks, illustrating how incredibly complex and interdependent this activity is. Relevant factors of the current state-of-the-art anomaly response were established through a literature review in combination with an established taxonomy process. These factors were then assessed for their Earth-reliance specific attributes through a case study. In this paper we have identified over 120 relevant anomaly response factors and developed a process that allows for identifying system capabilities that need to be integrated into future habitat designs to provide a minimum level self-sufficiency to protect crews from catastrophic outcomes stemming from communications delays and compounding co-dependency of factors. While this process was demonstrated using notional Mars mission constraints and evaluated against current ISS processes as the baseline, the outlined approach can be adapted for anomaly response designs that require different forms of system autonomy by modifying the relevant mission constraints and operational capability attributes accordingly.

Key Success Factors for Co-Working Space Business Model

Co-working spaces have gained popularity in recent years as a flexible and cost-effective solution for freelancers, startups, and small businesses looking for a collaborative work environment. This article examines the key success factors for a co-working space business model, drawing on insights from industry experts and research studies. By identifying these critical factors, co-working space operators can optimize their business model and enhance their chances of success in a competitive market. The development of the use of co-working space is now increasingly promising. Many of the startup companies and freelancers who use co-working space as a place for daily activities to work. Co-working space also helps to differentiate work and daily activities from these workers. However, the business model of co-working space is relatively vulnerable. This study aims to evaluate the factors that can increase the success of the co-working space business model, considering the importance of co-working space as the development of creativity. This study involved 116 users from two businesses that achieved success in managing the co-working space. Data was collected using a questionnaire survey and structurally analyzed using SmartPLS. The results of the study identified that shared workspace management and supporting co-working space operations played an important role in determining the success of this business model. Membership management has no significant effect. Therefore, the management of co-working space can be focused on these two elements

PSF-C-Net: A Counterfactual Deep Learning Model for Person Re-Identification Based on Random Cropping Patch and Shuffling Filling

In the task of person re-identification (re-ID), capturing the long-range dependency of instances is crucial for accurate identification. The existing methods excel at extracting local features but often overlook the global information of instance images. To address this limitation, we propose a convolution-based counterfactual learning framework, called PSF-C-Net, to focus on global information rather than local detailed features. PSF-C-Net adopts a parameter-sharing dual-path structure to perform counterfactual operations in the prediction space. It takes both the actual instance image and a counterfactual instance image that disrupts the contextual relationship as the input. The counterfactual framework enables the interpretable modeling of global features without introducing additional parameters. Additionally, we propose a novel method for generating counterfactual instance images, which effectively constructs an explicit counterfactual space, to reliably implement counterfactual strategies. We have conducted extensive experiments to evaluate the performance of PSF-C-Net on the Market-1501 and Duke-MTMC-reID datasets. The results demonstrate that PSF-C-Net achieves state-of-the-art performance.

Obligations and liabilities concerning the active removal of foreign space debris: A global governance perspective

Eliminating space debris in valuable Earth orbits is an urgent challenge for the sustainable development of outer space, and active removal is considered the most effective measure for debris elimination. In terms of legal jurisdiction, any country intending to remove space debris belonging to other countries undergoes a legality review encompassing obligations and liabilities. According to the fundamental principles of international space law, both threatened and capable countries possess the right to actively remove identifiable space debris of foreign nations, subject to strict legal obligations towards the registry country unless authorized by the United Nations, granted an agreement on jurisdiction transfer of debris, or justified by emergency necessity. Moreover, active removal may result in third-party space objects or personnel damage, imposing a substantial liability burden that could restrict space operation. Henceforth, it is imperative to establish a more rational legal regime for space liability allocation purposes. The international community can establish a mechanism for liability sharing and cross-waiver agreements among relevant countries while also considering potential fund establishment, involvement of non-governmental entities in cost-sharing efforts, and promoting commercial recycling initiatives as potentially motivating measures towards active removal.

თანამედროვე მიდგომები საბანკო რეგულირებისადმი ციფრული ტექნოლოგიების განვითარების პირობებში

The development of digital technologies has a great impact on traditional channels for providing banking services. The speed of introduction of innovative products and services, technological changes require great flexibility from banking regulators. Also, the active participation of the government in the development of digital technologies is one of the main factors of successful digitalization. In modern conditions, in order to ensure the development of innovation in the banking sector, new mechanisms and instruments for regulating innovative financial technologies, products and services are being created. The article specifies that the effective, safe operation and development of the digital financial space requires coordinated actions from all its participants, as well as the establishment of requirements for the assessment and monitoring of potential risks caused by innovations, timely improvement and refinement of regulatory requirements. This allows to maintain the stability of the financial system and protect the rights of consumers, and to promote the development and introduction of innovative financial products and services.

Biomorph Soft Actuators with Tardigrade‐Like Resilience

AbstractTardigrades are the most resilient biospecies on Earth, capable of surviving extreme conditions including high temperatures, pressures, air deprivation, and exposure to noxious chemicals and radiation. The study here undertakes biomimicry of the remarkable adaptability of tardigrades by designing biomorph soft actuators (BSAs) that can endure these harsh environments. Unlike previous tardigrade‐inspired materials, which lacked a naturalistic interaction with their surroundings, the BSAs replicate the anatomical macrostructures and the non‐monotonic environmental resilience of tardigrades, especially their ability to adapt via dehydration and rehydration. Dual‐layer hydrogel spheres are employed with embedded fluid bubbles, creating cohesive yet non‐monolithic smart BSA structures. These structures exhibit high resilience to compressive, thermal, and radiation stimuli, achieved through thermoresponsive shape morphing driven by fluid balance. Their advanced capabilities are also demonstrated, such as driving a McKibben‐type artificial muscle and rapidly regenerating themselves from a state exposed to hazardous chemicals. Such versatile actuating biomorphs hold great promise for various autonomous applications, including soft robotic operations in aqueous effluents, deserts, polar regions, and outer space.

Dynamic Usage Allocation and Pricing for Curb Space Operation

Dynamic Usage Allocation and Pricing for Curb Space Operation

Pathways to global coordination in space weather: International organizations, initiatives, and space agencies

This paper is the second part of two papers on global coordination in space weather. In this paper the activities of established and emerging international organizations and initiatives related to space weather research and operations are introduced. As shown in the accompanying paper “Global Landscape of Space Weather Observations, Research and Operations”, most of instrumentations for space environment monitoring are operated by each country. On the other hand, it is necessary to integrate the global observation to detect space weather phenomena, and it is essential to coordinate among nations for data sharing, set standard formats and protocols, fill observational gaps, etc. There are multiple international organizations and other actors in the field of space weather, and they have their own purposes and goals. In 2022, three international organizations, WMO, ISES and COSPAR reached an agreement to explore pathways to increased coordination of activities. There is also an emerging movement by various space agencies that fund space weather research missions to establish a forum to share plans and foster discussions leading to possible collaborations that advance understanding and enable progress of space weather operations and applications.

Improving the knowledge of the orbital population New technical means of space debris monitoring

Space objects monitoring data represents the foundation of any Space Traffic Management system, as it provides inputs both for operational needs (e.g. collision avoidance), but also to space debris models to assess the status and evolution of the debris environment. The current paper provides an overview of current techniques used for space object observation, ranging from radar to in-situ system, together with a survey of emerging technologies and recommendations for evolution in view of observed trends in space operations (e.g. need for improved collision avoidance data, increase in rideshare missions, development of active debris removal and servicing missions).

Cryogenics performance enhancement of epoxy resin composites through negative expansion nanomaterials: Mechanism and predictive modeling

AbstractThe matrix cracking of carbon fiber reinforced epoxy resin based composites (CFRPs) at cryogenics (such as liquid nitrogen temperature) is a major issue affecting the normal operation of deep space and deep‐sea detectors, as microcracks caused by the thermal residual stress of both can reduce the structural integrity of the devices. In this work, we report an epoxy (EP) nanofiller CuO nanorods (CuO NRs) with negative thermal expansion properties at cryogenics. Experiments showed that CuO NRs can effectively inhibit the shrinkage of EP at cryogenics and improve the mechanical properties of EP at cryogenics. A temperature dependent prediction model for the tensile strength of EP/CuO NRs was proposed, and the predicted results were in good agreement with experimental results. Finally, through a combination of experiments and theory, it was demonstrated that the tensile strength of EP/CuO NRs at cryogenics is jointly enhanced by the enhancement effect of the nanomaterials and the axial compressive thermal residual stress between EP and CuO NRs.Highlights Successfully prepared CuO nanorods with negative expansion properties at low temperatures, and found that they can effectively inhibit the shrinkage of epoxy resin at cryogenics. At cryogenics, the expansion of CuO nanorods enhances their interface effect with epoxy resin and improves the tensile strength of epoxy resin composites. The theory of tensile strength of epoxy resin at cryogenics was proposed for the first time. Theoretical analysis shows that the low temperature residual thermal stress between CuO nanorods and epoxy resin is the main factor to improve its tensile strength.

Positioning of a lunar surface rover on the south pole using LCNS and DEMs

With the renewed interest in the lunar surface exploration, the European Space Agency is supporting, as part of the Moonlight program, the development of a dedicated Lunar Communications and Navigation Service (LCNS) infrastructure. This should enable to achieve real time positioning and autonomous navigation in the cislunar space, including, among others, lunar landing and surface operations. One of the services proposed, as part of the LunaNet framework (NASA, 2022), is called the Lunar Augmented Navigation Service (LANS) and it is based on a GNSS-like concept. However, compared to Earth-based GNSS, the expected number of available satellites in lunar orbit will initially be limited, which triggers the interest of coupling these technologies at the receiver level with other navigation data sources. In the case of surface rovers, use of digital elevation model (DEM) data has shown to be a potential other source of information to support positioning. The purpose of this contribution is to look at the actual navigation performances achievable when using a simple (four satellites constellation) lunar radio navigation constellation combined with a DEM, through a state estimation filter, for different rover dynamic and different DEM accuracy levels. It is shown that a 5 meter real-time horizontal position accuracy can be achieved, for 99.7% of the time, using a precise enough DEM (5 m/pixel) and a 4 satellite-constellation under different rover’s dynamic conditions (i.e. velocities).

An Index Description of the General Characteristics of Thermospheric Density Based on the Two‐Line‐Element Data Sets and the Spectral Whitening Method

AbstractThe thermospheric density and its variations are crucial to aerospace activities as well as space weather research and operation. However, due to the difficulties in observing the thermosphere, there has been a lack of effective descriptions for the general characteristics of thermospheric density. In this paper, the Two‐Line‐Element data sets (TLEs) from multi‐target low Earth orbit satellites are used to derive a proxy of the daily average atmospheric density in the thermospheric shell located in the vicinity of LEOs' orbital altitude. It captures the overall characteristics of the thermosphere and exhibits good correlations (∼0.9) with modeled and observed thermospheric density. By applying the spectral whitening method to this proxy, a new index is derived to describe non‐periodic perturbation of the density where the specific satellite passed by. The fact that the obtained from different satellites within the same thermospheric shell presents significant consistency to each other means that the new index is a good indicator for the overall feature of the variations of thermospheric density, and it is possible to define a unified regional index to describe density disturbances for the thermospheric shell where these satellites fly through. Moreover, the at different altitudes also present good consistency suggesting the possibility of defining a global index , capable of describing the density variation of the entire thermosphere.

Preliminary investigation and proposal of periodic orbits and their utilization for logistics in the cislunar regime

The world is in the midst of what is widely considered the second Space Age due to the vastly growing commercial space sector and progress with international initiatives such as the Artemis program, led by the National Aeronautics and Space Administration (NASA). Cislunar space is becoming a region of growing interest as nations, international organizations, and private corporations look to expand their presence and outreach. The planned development of space infrastructure, such as lunar habitats, mining operations, and other installations, is driving the need for studies regarding common orbital pathways to ensure logistical support for future cislunar missions. Along with common orbital pathways, comprehensive and internationally acknowledged space policy and doctrine is required to ensure the safety, stability, and peace of this new frontier of human endeavor. This study serves to address one of the mission sets that will come to shape the emerging economy of the wider Earth-Moon system, space logistics. Specifically, this study will discuss potential orbits for a cislunar space situational awareness network that would support a space traffic management service, along with three cislunar logistics missions: personnel and cargo transport, space tourism, and search and rescue. Characteristics considered for orbits include orbit stability, period, and the proximity to key nodes in cislunar space such as the Moon and Lagrange points. Using Circular Restricted Three-Body Problem (CR3BP) dynamics, fourteen sample cislunar periodic orbits are proposed to accomplish the cislunar missions discussed. This study adds to the limited work in the field of cislunar orbital design to generate novel orbits and apply them to logistical use cases. All missions, except tourism, feature a “touring” class of cislunar periodic orbits due to their unique geometries enabling them to traverse a wide range of cislunar space. Preliminary analysis indicates that all of the proposed orbits are classified as marginally unstable, and suggests that minimal propellant is required to maintain a space vehicle's intended cislunar trajectory. Finally, existing law, policy, and governance surrounding cislunar space logistics and operations is discussed specifically concerning space traffic management, transportation, and humans touring or being rescued from space. Special attention is given to both the ambiguity of the law and the limitations of current norms of behavior, patent and property concerns, and tense geopolitical situations that can further complicate peace. Overall, this study highlights the underdevelopment of current space law and policy with the ambiguity of present-day norms discussed.

Synthetic orbit uncertainty generation through regression analysis of historical Conjunction Data Messages

In the last decades, the Earth-orbiting population of both active and non-active objects has grown significantly, leading to a substantial increase in number of possible in-orbit collisions. It is therefore crucial to monitor the orbit of space resident objects to assess in advance the threat of risky conjunctions. Within this framework, the 18th Space Defense Squadron (SDS) is consistently updating the orbit of thousands of tracked objects by processing observations of the U.S. Space Surveillance Network (SSN). The determined orbital data is continuously maintained in the Special Perturbation (SP) catalogue and used by the 19th SDS to issue close approach warnings to satellite operators around the globe in the form of Conjunction Data Messages (CDM). The Flight Dynamics (FD) group of the German Space Operation Centre (GSOC) receives on regular basis a subset of the SP catalogue data along with CDMs associated to the fleet of its controlled satellites. The SP ephemerides are in fact provided without any covariance information preventing any computation of the Probability of Collision (Pc). In GSOC FD we are implementing a service to link a series of synthetic orbital error covariance matrices to a given SP ephemeris by statistically analyzing historical CDMs of past events. More than 30 GB of past conjunction data are processed to extract state vector, covariance matrix and object size parameter of already encountered secondary objects. The orbital errors of these last are subsequently categorized and divided into orbital classes to decouple the high correlation the covariance has with respect to solar flux, object dimension, altitude of perigee, eccentricity and orbit inclination. The classification aims at collecting similar CDMs regarding the aforementioned dependencies, and approximates the predicted 1-sigma position errors in the orbital frame by optimal curve-fitting techniques. By evaluation of the curve fitting coefficients of a requested orbit class a covariance matrix can be generated for any prediction time in upcoming CDM refinements and other analyses. The work discusses the limiting cases of the classification approach, bringing possible solutions to the scenario of empty classes. An in-depth characterization of the parameters that affect the orbital errors is in fact performed to individualize the neighboring class that provides the closest and most meaningful covariance timeline. Successively, the effect of using synthetic covariance in a conjunction risk assessment is also explored, adapting the problem on real operations. Lastly, the entire data processing pipeline and how the described service fits into the GSOC Flight Dynamics System (FDS) framework is described.

An example related to Whitney’s extension problem for L 2,p (R2) when 1 < p < 2

Abstract In this paper, we prove the existence of a bounded linear extension operator T : L 2 , p ( E ) → L 2 , p ( R 2 ) $T:{L}^{2,p}\left(E\right)\to {L}^{2,p}\left({\mathbb{R}}^{2}\right)$ when 1 < p < 2, where E ⊂ R 2 $E\subset {\mathbb{R}}^{2}$ is a certain discrete set with fractal structure. Our proof makes use of a theorem of Fefferman–Klartag (“Linear extension operators for Sobolev spaces on radially symmetric binary trees,” Adv. Nonlinear Stud., vol. 23, no. 1, p. 20220075, 2023) on the existence of linear extension operators for radially symmetric binary trees.

Stress stiffening effects in flexible Earth observation satellites with spinning appendage

Modern satellites often adopt innovative configurations to meet the escalating requirements of space operations. This study specifically focuses on one such configuration, exemplified by an Earth observation spacecraft equipped with a large rotating payload connected to the main bus through a flexible boom. The rotational motion of the payload is designed to extend the scanned area, resulting in a substantial reduction in the time required to complete a set of measurements, thus enhancing the overall performance. However, this configuration introduces greater complexity both in the analysis of the dynamical behavior and in the design of the control architecture. When dealing with flexible structures subject to rotational motion, as in this scenario, the stiffening effect resulting from inertial loads—particularly the centrifugal action—becomes crucial. In this study, we derive the dynamic equations of the multibody flexible spacecraft using Kane's formulation, which provides a streamlined set of ordinary differential equations by simplifying their derivation. Treating the link as an elastic beam, flexibility is incorporated through a modal decomposition approach that considers nonlinear elastic dynamics, ensuring the inclusion of stress stiffening in the dynamical model. Stress stiffening emerges as a fundamental effect in spinning space structures, where the contribution of the centrifugal force is significant. Incorrect predictions and structural instability for high spinning rates are observed when this effect is neglected. Furthermore, the error associated with overlooking this physical phenomenon is found to be dependent on the spinning rate. We identify kinematical conditions that render this effect negligible in relation to the fundamental deformation frequencies of the space system. Several numerical results are presented and discussed.

Cascade PID Control for Altitude and Angular Position Stabilization of 6-DOF UAV Quadcopter

UAVs are commonly used in transportation, especially in the express delivery of light cargo parcels. However, controlling UAVs is difficult because of their complex structure and wide range of operations in space. The research contribution is proposed a cascade control structure using six PID controllers for the 6-DOF UAV quadcopter, that ensures the altitude angulars positions control at the desired values and maintains flight balance stability for the 6-DOF UAV quadcopter. First, the mathematical dynamic models for the 6-DOF UAV quadcopter have been researched and developed, including the translational dynamic mathematical model and the rotational dynamic mathematical model of the 6-DOF UAV quadcopter. This is a complex object with strong nonlinearity and difficult control. And then, the article introduces the method of designing six PID controllers for 6-DOF UAV quadcopter to meet the requirements, based on applying the Ziegler-Nichols experimental method. Applying the Ziegler-Nichols experimental method makes the process of designing a UAV quadcopter control system simple, straightforward and heuristics with fast controller parameters tuning. Next, the article presents the results of modeling and simulation of the 6-DOF UAV quadcopter control system on Matlab/Simulink. The simulation results show that the six proposed PID controllers have ensured the flight balance stability at the desired altitude and angular positions with overshoot less than 20%, steady-state error less than 1%. This shows the prospect of applying the proposed PID control method to physical UAVs, easily adjusting PID parameters to suit the flight environment.

Train Station Pedestrian Monitoring Pilot Study Using an Artificial Intelligence Approach.

Pedestrian monitoring in crowded areas like train stations has an important impact in the overall operation and management of those public spaces. An organized distribution of the different elements located inside a station will contribute not only to the safety of all passengers but will also allow for a more efficient process of the regular activities including entering/leaving the station, boarding/alighting from trains, and waiting. This improved distribution only comes by obtaining sufficiently accurate information on passengers' positions, and their derivatives like speeds, densities, traffic flow. The work described here addresses this need by using an artificial intelligence approach based on computational vision and convolutional neural networks. From the available videos taken regularly at subways stations, two methods are tested. One is based on tracking each person's bounding box from which filtered 3D kinematics are derived, including position, velocity and density. Another infers the pose and activity that a person has by analyzing its main body key points. Measurements of these quantities would enable a sensible and efficient design of inner spaces in places like railway and subway stations.

Modeling and simulation of earth coverage of a low earth orbit (LEO) satellite

Efficient management of operations in near space, just beyond the Earth’s atmosphere, relies on the precise control of satellites positioned relatively close to our planet. Satellite systems, serving critical functions in telecommunications, observation, exploration, and more, have demonstrated their prowess as a transformative technology, consistently delivering high-precision data over numerous years. Among satellite systems, Low Earth Orbit (LEO) technology is gaining prominence due to its advantages, including lower power requirements for transmission, reduced propagation delays, and heightened coverage for polar regions. Achieving optimal efficiency from LEO satellites necessitates a thorough understanding of their fundamental orbital parameters and precise control over them. This study explores the orbital analysis and Earth coverage considerations of LEO satellites, scrutinizing orbital parameters in detail to compute coverage areas across various scenarios. Through this investigation, the potential benefits of data exchange with ground stations facilitated by LEO satellites are explored. In addition, the implications are discussed regarding the adjustment of data exchange topologies according to geographical locations and country borders.