Search

Off-the-shelf multicore systems are increasingly used in real-time fields, but hardware resource contention remains a key challenge. This work focuses on statically scheduled systems, common in real-time computing, and introduces a novel model for calculating worst-case contention delays. Under realistic assumptions, our model provides tight upper limits on these delays, considering the timing interference from other cores and their task sets. We present comprehensive evaluations demonstrating that our approach yields more accurate contention bounds compared to existing solutions. Additionally, we introduce an automated framework that simplifies the integration of our model into real-world scenarios, making it practical for industry professionals. This work not only tackles a critical issue in real-time multicore systems but also offers a precise, practical solution for managing inter-core timing interference. [ABSTRACT FROM AUTHOR]

The objective of this research is to investigate the computational efficiency of various system architectures of onboard software for the onboard computers of CubeSat nanosatellites. The subject of this study is the computing overhead associated with using the containerization method in the construction of the onboard software for CubeSat nanosatellites. Purpose: To experimentally investigate the possibility and feasibility of using the containerization method in the onboard software of CubeSat nanosatellites. Objectives: to define the need to find new architectural solutions in the onboard software of the CubeSat nanosatellite; to perform a comparative analysis of the advantages and disadvantages of using monolithic (classical) and microservice architecture in the onboard software of the CubeSat nanosatellite; to justify the choice of the system software environment for executing containers; to determine the typical structure of CubeSat software and the strategy for adapting the WASM3 container environment to the FreeRTOS operating system; to develop a plan; and to conduct an expert evaluation based on the results of the evaluation to formulate conclusions about the possibility and feasibility of using container architecture in the onboard software of the CubeSat nanosatellite. Conclusions. This study demonstrates the relevance of developing software for satellites based on microservices and containers. The experimental results allow us to compare the performance of the onboard computer when executing various algorithms implemented using the C programming language (“Bare-Metal” approach) and the architecture based on the microservices approach, branched between containers of the WASM3 environment running under the FreeRTOS, and developed in C and C++ programming languages. The main conclusion of this work is the potential of using the Falco SBC/CDHM hardware platform as an affordable and powerful computing platform for CubeSat nanosatellites.

The thermal analysis of stratospheric balloon payloads is still a complex task due to the variable thermal environment during the flight phases as well as due to the convective effects during the ascent. An experiment named HERCCULES has been successfully launched from Esrange Space Centre (Kiruna, Sweden) in September 2023 as part of the REXUS/BEXUS programme. This experiment aimed of serving as a heat transfer and thermal environment characterization platform that allow to validate previously developed methodologies for the worst-case thermal environmental conditions' selection and the thermal analysis of these platforms. The experiment has been developed in an academic environment and the design, manufacturing, integration and test activities were mainly performed by Bachelor, Master and Ph.D. students with the mentorship of the European Space Agency. A low-cost design was achieved by using Commercial Off-the-Shelf (COTS) without compromising its performance capabilities. The obtained measurements show a colder behavior of the external elements with regard to the worst-case analysis during the first part of the ascent phase. In addition, radiative fluxes measured during the flight show a deviation in the infrared downward flux of about -50 W m−2 at 5 km of altitude and a maximum fluctuation of about the 20% in the solar fluxes measurements. Significant advancements have been made for similar missions in terms of mechanical standardization, the use of COTS sensors and electronic components, the improvement of the reliability of the thermal analysis and the development of a software design adhered to standards and recommendations for critical systems. • A university experiment for a stratospheric balloon flight has been design using COTS. • The heat transfer and thermal environment characterization experiments on board HERCCULES are described. • An overview of the mechanical, electronic, thermal and software design and tests is included. • Preliminary results of the flight on board BEXUS 32 are presented. [ABSTRACT FROM AUTHOR]

System design in defense systems is a competitive field, in which economical viability relies on a sequence of architectural decisions, aiming at quality, resource and time (Q,R,T) compromises. We observe that low‐cost unmanned ground vehicles (UGV) and drones appear as new threats on current battlefield. To face these new threats, Direction Générale de l'Armement (DGA) have organized challenges around robotization of battlefield, to design future employment doctrines and help technologies to reach maturity in a reasonable time. This article exposes a NATO Architecture Framework (NAF) 3.1‐based workflow that includes return of experience form the field over yearly iterations of such challenges. The capabilities depicted are requirements to match, constituent systems are based on Components‐Off‐The‐Shelf (COTS) answering to both edition of the challenge. This article details how manually re‐injecting feedback from field back to the system model failed to ensure the next iterations of the challenge. Our works propose conclusions on formulation of the "engineering leakage problem" and how resolution of this problem is NP‐Hard and should be addressed using optimization. [ABSTRACT FROM AUTHOR]

Intraspecific and habitat-mediated responses to chemical cues play key roles in structuring populations of marine species. We investigated the behaviour of herbivorous-stage juvenile crown-of-thorns sea stars (COTS; Acanthaster sp.) in flow-through choice chambers to determine if chemical cues from their habitat influence movement and their transition to become coral predators. Juveniles at the diet transition stage were exposed to cues from their nursery habitat (coral rubble-crustose coralline algae (CCA)), live coral and adult COTS to determine if waterborne cues influence movement. In response to CCA and coral as sole cues, juveniles moved towards the cue source and when these cues were presented in combination, they exhibited a preference for coral. Juveniles moved away from adult COTS cues. Exposure to food cues (coral, CCA) in the presence of adult cues resulted in variable responses. Our results suggest a feedback mechanism whereby juvenile behaviour is mediated by adult chemical cues. Cues from the adult population may deter juveniles from the switch to corallivory. As outbreaks wane, juveniles released from competition may serve as a proximate source of outbreaks, supporting the juveniles-in-waiting hypothesis. The accumulation of juveniles within the reef infrastructure is an underappreciated potential source of COTS outbreaks that devastate coral reefs. [ABSTRACT FROM AUTHOR]

CubeSats are a type of spacecraft which have become popular since the early 2000. They are known for their quick development time and low cost, when comparing them to larger satellites. However, there is a significant drawback which has been recorded during these years of operations, namely an high failure rate which turns almost half of them into space debris. The reasons behind these malfunctions are often attributed to flawed spacecraft design choices or failures of commercial off-the-shelf (COTS) products. To improve the design of CubeSats, several software tools for performing the conceptual design have been proposed. These tools are often limited in their capabilities and are not suitable for all types of CubeSat missions. To address this issue, the University of Applied Sciences Wiener Neustadt (FHWN) in cooperation with Technische Universität Dresden is developing a software tool called GREATCUBE+. Its goal is to increase the success rate of CubeSats by providing a satellite model which is composed of commercial-off-the-shelf (COTS) products backed up by empirical heritage, analytical proof, and numerical analysis. One of the main features of this tool is the ability of dealing with different typologies of payloads. GREATCUBE+ has been validated with various successful CubeSat missions and it provides design solutions with an accuracy of above 90% when it comes to CubeSat weights and volumes. Using this software, CubeSat design teams can proceed from the conceptual development to the testing and assembly phases quicker, hoping to result in higher quality CubeSats and fewer failures. [ABSTRACT FROM AUTHOR]

Cleanrooms are controlled environments where the number of airborne particles is reduced to a level defined by an International Organization for Standardization (ISO) standard. These facilities have applications in different fields, such as the electronic, pharmaceutical, and healthcare sectors, and are also necessary for the assembly, testing and handling of space hardware. Cleanrooms are expensive to build and maintain and require the permanent designation of infrastructures and dedicated spaces within a building. Once built, clean rooms cannot be used for any other purpose, as contamination is a significant risk. The restricted access to these facilities limits the process of designing, testing, and calibrating instruments developed by academic institutions, small companies, and space startups. Here we present a Commercial Off-The-Shelf (COTS) procedure for building and maintaining a highly controlled ISO class 5 cleanroom, according to ISO14644 standards. We provide a detailed explanation of how to design, develop and operate a portable, modular, and cost-effective ISO class 5 cleanroom that can be used for the usual workflow of development, integration, test procedures and planetary protection associated with the design of instrumentation for planetary exploration.

Star trackers are crucial for satellite orientation. Improving their efficiency via reconfigurable COTS HW accommodates NewSpace missions. The current work considers SoC FPGAs to leverage both increased reprogramming and high-performance capabilities. Based on a custom sensor+FPGA system, we develop and optimize the algorithmic chain of star tracking by focusing on the acceleration of the image processing parts. We combine multiple circuit design techniques, such as low-level pipelining, word-length optimization, HW/SW co-processing, and parametric HLS+HDL coding, to fine-tune our implementation on Zynq-7020 FPGA when using real and synthetic input data. Overall, with 4-MPixel images, we achieve more than 24 FPS throughput by accelerating >95% of the computation by 8.9 × , at system level, while preserving the original SW accuracy and meeting the real-time requirements of the application. [ABSTRACT FROM AUTHOR]

In the framework of the NewSpace revolution, time-to–market and budget constraints drive the development of small and medium-sized satellites in Low Earth Orbit (LEO) orbit. The adoption of Commercial Off-the–Shelf (COTS) components represents the current trend to fulfill the NewSpace goals, given their low cost, wide product availability, small time-to–market, and the ability to integrate the most recent advancements in space applications. However, migrating from radiation-hardened (rad-hard) devices to COTS ones requires ensuring comparable reliability levels. To this end, an “up-screening” of the COTS devices and systems should be performed in compliance with widely adopted standard regulations, such as those used by ESA or NASA. In this paper, we review COTS components and systems, such as diodes, Bipolar Junction Transistors (BJTs), Field Effect Transistors (FETs), Operational Amplifiers (OPAMPs), memories, and Field Programmable Gate Arrays (FPGAs), proven-flight or ad-hoc tested for compliance with standard regulations. In conclusion, the most promising devices in terms of cost and radiation tolerances are identified, providing useful benchmarks for space engineers developing COTS-based innovative systems.

With an increasing need for enormous amount of computing power, different approaches for building inexpensive supercomputers have emerged. Decreasing costs and continuous technology scaling has led to the emergence of computers with ARM processors which are considered as a possible alternative to traditional x86 processors for creating High Performance Computing (HPC) systems. The aim of this research is to carry out a detailed performance evaluation of a cluster of ARM-based computers against a comparable low-cost cluster of x86-based computers and investigates whether these ARM processors are capable to substitute x86 processors for creating HPC clusters. Our methodology is based on experimental evaluation by setting up two cluster architectures. To compare the performances of both clusters, two complex applications were implemented: approximation of mathematical constant PI (3.14), a matrix multiplication program. Our analysis focused on execution time and speedup as performance metrics. From the results we observed that maximum performance achieved by both clusters is when the number of MPI processes are equal to the number of processing nodes on the cluster thereby allowing a one-to-one mapping of the tasks with minimal overhead. If we compare the maximum performances of both clusters in terms of execution time, the x86-Cluster performed 1.16× and 2.42× faster than the ARM-Cluster for pi_calculation and matrix_mul benchmarks. However, we noted that the ARM-based cluster exhibited superior speedup compared to the x86-based cluster, potentially attributed to the greater number of cores per node used in the ARM cluster. From the comparative performance evaluation, we conclude that ARM processors substantially lag behind x86 processors not only because of their limited resources but due to major difference between their instruction sets and architecture especially when it comes to memory-bound operations. This research underscores the challenges and opportunities associated with ARM processors in the context of HPC clusters, offering valuable insights to the scientific community looking for cost-effective computing solutions.

The NewSpace approach of utilizing CubeSats and smaller satellites for complex LEO missions that once were reserved only for bigger platform, paired with the requirement of enduring reliability and quality assurance on batches of tens of satellites, is paving the way for the use of commercial-off-the-shelf (COTS) components in micro-satellite missions. The recent global supply chain issues and extended lead times in the procurement of micro-controllers, memories and passive electronic components, caused by the pandemic and factories shutdowns, have resulted in a forced procurement diversification of several key elements, even in partially assembled products. GAUSS has been designing, manufacturing, and launching Small Satellites since early 2000. Its tenth satellite, UNISAT-7, was launched by a Soyuz-Fregat LV on March 22nd, 2021. Thanks to the vast experience gained on the application of commercial components in all the subsystems developed by the company, the typical overall costs for a complete platform are substantially lower compared to competitors, while retaining similar reliability. UNISAT-7, developed using lean-satellite methodologies, included more than 28 independent subsystems with their own telemetry, and most of them were developed in-house using ground COTS components; no space-grade products were employed, to save on overall mission costs. Some systems were devised from the start using open-source hardware, to expedite the prototyping process, while having the benefit of using readily available software, generally included with these platforms. Raspberry embedded devices were employed on the flight model for two remote sensing systems, to test how such systems, duly adapted to sustain space conditions, may perform and show reliability similar to commercial space systems worth thousand times the value. All systems have been activated and successfully verified for an entire year in LEO. They were hardened for vacuum, extreme temperatures, radiation, and launch stresses using common items found in general hardware stores. This work will delve into the open-source/COTS components used, the process employed to strengthen them, and the programmed flight firmware routines for maximizing embedded devices' reliability in space. • Use of commercial-off-the-shelf (COTS) components in micro-satellite missions • UNISAT-7 as a space-tug, to deploy CubeSats and PocketQubes in LEO • GAUSS experience on COTS usage for micro- and nano-satellite missions • Use of open-source embedded systems in micro and nano-satellite missions • Best practices to enhance low-cost COTS reliability [ABSTRACT FROM AUTHOR]

Low Earth orbit missions have become crucial for a variety of applications, from scientific research to commercial purposes. Exposure to ionizing radiation in Low Earth Orbit (LEO) poses a significant risk to both spacecraft and astronauts. In this article, we analyze radiation data obtained from different LEO missions to evaluate the potential of using electronic commercial off-the-shelf (COTS) devices in space missions. This study is focused on the total ionizing dose (TID). Our results demonstrate that COTS technology can effectively provide cost-effective and reliable solutions for space applications. Furthermore, we compare the data obtained from actual missions with computational models and tools, such as SPENVIS, to evaluate the accuracy of these models and enhance radiation exposure prediction. This comparison provides valuable insights into the true radiation environment in space and helps us to better understand the potential of COTS technology in reducing costs and development times by utilizing technology previously used in other areas. In light of the results, we can see that the radiation values observed experimentally in space missions versus the computer simulations used present variations up to a factor of 30 depending on the model used in the analysis. [ABSTRACT FROM AUTHOR]

Spaceborne Global Navigation Satellite Systems (GNSS) receivers have become ubiquitous sensors for spacecraft navigation, especially in Low Earth Orbits (LEOs), often also supporting science endeavors or as acting dedicated science payloads. Due to the large number of space-capable GNSS receiver models available, spacecraft designers, as well as scientists, may find it difficult to have or gain an overview of suitable state-of-the-art models for their purposes and constraints. Based on a literature review that included more than 90 different receiver models, this paper aims to provide an overview of space-capable GNSS receivers that have a heritage in space missions. It analyses trends from the collected data and provides an outlook on miniaturized GNSS receiver models, which have a high potential of being used in future space missions. [ABSTRACT FROM AUTHOR]

All-sky cameras capture a panoramic view of the full sky from horizon to horizon to generate a wide-angle image of the observable sky. State-of-the-art all-sky imagers are limited to imaging in the visible and infrared spectrum and cannot image in the UV spectrum. This article describes the development of an all-sky imaging system capable of capturing 130° wide-angle sky images from horizon to horizon in the UV-AB spectrum. The design of the UV all-sky imaging system is based on low-cost, accessible, and scalable components to develop multiple images that can be deployed over a wider geographical area. The spectral response of the camera system has been validated in the UV spectrum (280–420 nm) using a monochromatic UV beam with an average power output of 22 nW. UV all-sky imaging systems complement existing infrared and visible all-sky cameras. They have wide applications in astronomy, meteorology, atmospheric science, vulcanology, meteors and auroral monitoring, and the defence sector. [ABSTRACT FROM AUTHOR]

As a subclass of nanosatellites, CubeSats have changed the game's rules in the scientific research industry and the development of new space technologies. The main success factors are their cost effectiveness, relative ease of production, and predictable life cycle. CubeSats are very important for training future engineers: bachelor's and master's students of universities. At the same time, using CubeSats is a cost-effective method of nearest space exploration and scientific work. However, many issues are related to efficient time-limited development, software and system-level quality assurance, maintenance, and software reuse. In order to increase the flexibility and reduce the complexity of CubeSat projects, this article proposes a "hybrid" development model that combines the strengths of two approaches: the agile-a-like model for software and the waterfall model for hardware. The paper proposes a new computing platform solution, "Falco SBC/CDHM", based on Microchip (Atmel) ATSAMV71Q21 with improved performance. This type of platform emphasizes low-cost space hardware that can compete with space-grade platforms. The paper substantiates the architecture of onboard software based on microservices and containerization to break down complex software into relatively simple components that undergraduates and graduates can handle within their Master's studies, and postgraduates can use for scientific space projects. The checking of the effectiveness of the microservice architecture and the new proposed platform was carried out experimentally, involving the time spent on executing three typical algorithms of different algorithmic complexities. Algorithms were implemented using native C (Bare-metal) and WASM3 on FreeRTOS containers on two platforms, and performance was measured on both "Falco" and "Pi Pico" by Raspberry. The experiment confirmed the feasibility of the complex application of the "hybrid" development model and microservices and container-based architecture. The proposed approach makes it possible to develop complex software in teams of inexperienced students, minimize risks, provide reusability, and thus increase the attractiveness of CubeSat student projects. [ABSTRACT FROM AUTHOR]

With an increasing need for enormous amount of computing power, different approaches for building inexpensive supercomputers have emerged. Decreasing costs and continuous technology scaling has led to the emergence of computers with ARM processors which are considered as a possible alternative to traditional x86 processors for creating High Performance Computing (HPC) systems. The aim of this research is to carry out a detailed performance evaluation of a cluster of ARM-based computers against a comparable low-cost cluster of x86-based computers and investigates whether these ARM processors are capable to substitute x86 processors for creating HPC clusters. Our methodology is based on experimental evaluation by setting up two cluster architectures. To compare the performances of both clusters, two complex applications were implemented: approximation of mathematical constant PI (3.14), a matrix multiplication program. Our analysis focused on execution time and speedup as performance metrics. From the results we observed that maximum performance achieved by both clusters is when the number of MPI processes are equal to the number of processing nodes on the cluster thereby allowing a one-to-one mapping of the tasks with minimal overhead. If we compare the maximum performances of both clusters in terms of execution time, the x86-Cluster performed 1.16× and 2.42× faster than the ARM-Cluster for pi_calculation and matrix_mul benchmarks. However, we noted that the ARM-based cluster exhibited superior speedup compared to the x86-based cluster, potentially attributed to the greater number of cores per node used in the ARM cluster. From the comparative performance evaluation, we conclude that ARM processors substantially lag behind x86 processors not only because of their limited resources but due to major difference between their instruction sets and architecture especially when it comes to memory-bound operations. This research underscores the challenges and opportunities associated with ARM processors in the context of HPC clusters, offering valuable insights to the scientific community looking for cost-effective computing solutions. [ABSTRACT FROM AUTHOR]

Development of satellite technologies is a challenging task, which includes design, manufacturing, testing, and in-orbit operation stages. The reliability of each subsystem shall be at the highest level since space has severe environmental conditions and most satellites do not have an opportunity to perform repairment or replacement of their hardware components. In-orbit reprogramming of some devices, such as On-board Computer (OBC), Attitude Control Unit (ACU), and Power Control Unit (PCU) can provide great advantages to a mission by extending the lifetime and performance of a satellite's operation. At the same time, even a small mistake can result in a lot of monetary losses or even failure of a subsystem or the whole project. So, a reprogramming method to be used in space missions shall undergo excessive testing to provide high reliability for updating software in orbit. This paper is devoted to an investigation of available and applicable methods for remote reprogramming of Field-Programmable Gate Array (FPGA) based subsystems. A commercial off-the-shelf (COTS) single board computer (SBC) was used as a standalone subsystem to perform reprogramming of a target device. The SBC was tested extensively and reinforced for ensuring its space-compatibility. Several open-source software-based solutions were considered. Some of them are applicable to a wide range of processor architectures, including ARM. Considered methods could reconfigure an FPGA successfully with some major limitations, which were also described in the paper. Based on the investigation, Xilinx Software Command-line Tool (XSCT) was selected as a reprogramming method for ACU of the latest satellite of iQPS, QPS-SAR-2 ("IZANAMI"). [ABSTRACT FROM AUTHOR]

Commercial-off-the-Shelf (COTS) component selection is considered a critical task in effectively developing a component-based software system (CBSS). COTS vendor selection involves selecting the right vendors who can provide reliable COTS components at a suitable price and on time. However, COTS vendor selection is commonly a multi-criteria decision-making (MCDM) issue" associated with many paradoxical criteria for which the decision maker's knowledge may be uncertain and ambiguous. This paper attempts to present "Intuitionistic Fuzzy Sets (IFS) combined with the technique for order preference by similarity to an ideal solution (TOPSIS) method" to appraise and choose the best COTS vendor under the environment of group decision making while considering reliability, delivery time, compatibility, vendor support and functionality as benefit criteria. In contrast, price and maintenance be the cost criteria. The considered case study demonstrated the presented case effectively. [ABSTRACT FROM AUTHOR]

Alpha particle spectroscopy is highly significant in technologies related to radioactivity, particularly in radiation safety and the study of natural radioactivity. On the other hand, tools capable of identifying and determining the energies of alpha particles are of great interest. Among these tools, Commercial Off-The-Shelf (COTS) instruments, which can be used for alpha particle detection, have gained significant importance due to their ease of use and low cost. In this study, alpha particle spectroscopy of a Ra-226 source has been performed using a commercial digital camera based-on a CMOS sensor. In order to determine energy spectrum of alpha particles emitted from the source, the performance of various edge detection algorithms was examined. An algorithm based-on local pixel changes was introduced and implemented. By comparing the run times of the algorithms, it was shown that the algorithm proposed in this article exhibited the shortest run-time. Additionally, a method for rejecting pile-up events to correct their destructive effects on the alpha particle energy spectrum was introduced and implemented. • Alpha particle spectroscopy has performed by a digital USB camera. • The cooling system reduces the noise in the CMOS sensor. • A new and fast method for edge detection algorithm has been introduced. • A new pile-up rejection method has been applied. • The energy resolution improves by pile-up rejection algorithm. [ABSTRACT FROM AUTHOR]

As a subclass of nanosatellites, CubeSats have changed the game’s rules in the scientific research industry and the development of new space technologies. The main success factors are their cost effectiveness, relative ease of production, and predictable life cycle. CubeSats are very important for training future engineers: bachelor’s and master’s students of universities. At the same time, using CubeSats is a cost-effective method of nearest space exploration and scientific work. However, many issues are related to efficient time-limited development, software and system-level quality assurance, maintenance, and software reuse. In order to increase the flexibility and reduce the complexity of CubeSat projects, this article proposes a “hybrid” development model that combines the strengths of two approaches: the agile-a-like model for software and the waterfall model for hardware. The paper proposes a new computing platform solution, “Falco SBC/CDHM”, based on Microchip (Atmel) ATSAMV71Q21 with improved performance. This type of platform emphasizes low-cost space hardware that can compete with space-grade platforms. The paper substantiates the architecture of onboard software based on microservices and containerization to break down complex software into relatively simple components that undergraduates and graduates can handle within their Master’s studies, and postgraduates can use for scientific space projects. The checking of the effectiveness of the microservice architecture and the new proposed platform was carried out experimentally, involving the time spent on executing three typical algorithms of different algorithmic complexities. Algorithms were implemented using native C (Bare-metal) and WASM3 on FreeRTOS containers on two platforms, and performance was measured on both “Falco” and “Pi Pico” by Raspberry. The experiment confirmed the feasibility of the complex application of the “hybrid” development model and microservices and container-based architecture. The proposed approach makes it possible to develop complex software in teams of inexperienced students, minimize risks, provide reusability, and thus increase the attractiveness of CubeSat student projects.

Spaceborne Global Navigation Satellite Systems (GNSS) receivers have become ubiquitous sensors for spacecraft navigation, especially in Low Earth Orbits (LEOs), often also supporting science endeavors or as acting dedicated science payloads. Due to the large number of space-capable GNSS receiver models available, spacecraft designers, as well as scientists, may find it difficult to have or gain an overview of suitable state-of-the-art models for their purposes and constraints. Based on a literature review that included more than 90 different receiver models, this paper aims to provide an overview of space-capable GNSS receivers that have a heritage in space missions. It analyses trends from the collected data and provides an outlook on miniaturized GNSS receiver models, which have a high potential of being used in future space missions.

All-sky cameras capture a panoramic view of the full sky from horizon to horizon to generate a wide-angle image of the observable sky. State-of-the-art all-sky imagers are limited to imaging in the visible and infrared spectrum and cannot image in the UV spectrum. This article describes the development of an all-sky imaging system capable of capturing 130° wide-angle sky images from horizon to horizon in the UV-AB spectrum. The design of the UV all-sky imaging system is based on low-cost, accessible, and scalable components to develop multiple images that can be deployed over a wider geographical area. The spectral response of the camera system has been validated in the UV spectrum (280–420 nm) using a monochromatic UV beam with an average power output of 22 nW. UV all-sky imaging systems complement existing infrared and visible all-sky cameras. They have wide applications in astronomy, meteorology, atmospheric science, vulcanology, meteors and auroral monitoring, and the defence sector.

In New Space, the need for reduced cost, higher performance, and more prompt delivery plans in radiation-harsh environments have motivated spacecraft designers to use Commercial-Off-The-Shelf (COTS) memories and emerging technology devices. This paper investigates the behavior of state-of-the-art memories manufactured in emerging technologies, including Ferroelectric Random-Access Memory (FRAM), Resistive Random-Access Memory (ReRAM), and Magnetic Random-Access Memory (MRAM), against radiation effects in static and dynamic modes. Radiation-ground tests were conducted under 15-MeV and 1-MeV protons, thermal and 14.8-MeV neutrons leading to various categories of radiation effects. Experimental results will show clear evidence of the robustness of bitcells manufactured using these emerging technologies against radiation, but at the same time, some susceptibility in these devices to suffer radiation effects when working in dynamic mode. Experimental results with the CY15B102Q and CY15B104Q FRAMs (Infineon Technologies), the MB85AS4MT, and MB85AS8MT ReRAMs (Fujitsu), and the MR10Q010CSC and MR25H40CDF MRAMs (Everspin) will be presented and discussed.

Assembly, Integration, and Verification/Testing (AIV or AIT) is a standardized guideline for projects to ensure consistency throughout spacecraft development phases. The goal of establishing such a guideline is to assist in planning and executing a successful mission. While AIV campaigns can help reduce risk, they can also take years to complete and be prohibitively costly for smaller new space programs, such as university CubeSat teams. This manuscript outlines a strategic approach to the traditional space industry AIV campaign through demonstration with a 6U CubeSat mission. The HYPerspectral Smallsat for Ocean observation (HYPSO-1) mission was developed by the Norwegian University of Science and Technology's (NTNU) SmallSatellite Laboratory in conjunction with NanoAvionics (the platform provider). The approach retains critical milestones of traditional AIV, outlines tailored testing procedures for the custom-built hyperspectral imager, and provides suggestions for faster development. A critical discussion of de-risking and design-driving decisions, such as imager configuration and machining custom parts, highlights the consequences that helped, or alternatively hindered, development timelines. This AIV approach has proven key for HYPSO-1's success, defining further development within the lab (e.g., already with the second-generation, HYPSO-2), and can be scaled to other small spacecraft programs throughout the new space industry. [ABSTRACT FROM AUTHOR]

Critical loss of habitat is the greatest threat to biodiversity, yet some species are inherently plastic to and may even benefit from changes in ecosystem states. The crown-of-thorns sea star (CoTS; Acanthaster spp.) may be one such organism. CoTS are large corallivores native to the tropical Indo-Pacific and in unexplained high densities, can adversely affect entire coral reefs. Proximal causes of CoTS outbreaks remain elusive, so this phenomenon remains a daunting and costly challenge for reef conservation and management. Amplifying anthropogenic impacts and new empirical data point to the degraded reef hypothesis to explain the episodic nature of CoTS population outbreaks. We posit that loss of live coral paradoxically benefits CoTS juveniles, which accumulate in their rubble nursery habitat before conditions trigger their pulsed emergence as coral-eaters. We review trait plasticity across the CoTS life cycle and present the degraded reef hypothesis in an integrative understanding of their propensity to outbreak., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Cleanrooms are controlled environments where the number of airborne particles is reduced to a level defined by an International Organization for Standardization (ISO) standard. These facilities have applications in different fields, such as the electronic, pharmaceutical, and healthcare sectors, and are also necessary for the assembly, testing and handling of space hardware. Cleanrooms are expensive to build and maintain and require the permanent designation of infrastructures and dedicated spaces within a building. Once built, clean rooms cannot be used for any other purpose, as contamination is a significant risk. The restricted access to these facilities limits the process of designing, testing, and calibrating instruments developed by academic institutions, small companies, and space startups. Here we present a Commercial Off-The-Shelf (COTS) procedure for building and maintaining a highly controlled ISO class 5 cleanroom, according to ISO14644 standards. We provide a detailed explanation of how to design, develop and operate a portable, modular, and cost-effective ISO class 5 cleanroom that can be used for the usual workflow of development, integration, test procedures and planetary protection associated with the design of instrumentation for planetary exploration., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Thasshwin Mathanlal reports financial support was provided by 10.13039/100011690UK Space Agency. Javier Martin-Torres reports financial support was provided by 10.13039/100011690UK Space Agency. Maria-Paz Zorzano reports financial support was provided by 10.13039/501100004837Spanish Ministry of Science and Innovation., (© 2024 The Authors.)

The lifecycle of a system is extended from its early conception to its retirement of service. The lifespan of Unmanned Ground Vehicles (UGVs) can be expected to last over 50 years in the defence market. In this context, the rising complexity of UGV systems imposes engineering steps that would ensure both capabilities of the system and resilience to its future inclusion in a system‐of‐system context. During its operational usage, the UGV is supposed to be manoeuvred for specifically designed purposes following user manual datasheet of the components off‐the‐shelf (COTS) that were integrated. This paper exposes the public user datasheet relevance compared to the system engineering requirements that are the artefacts of system design architecture. The use of connecting COTS user manual to system requirements is discussed, all the more if the systems are to be re‐used in a system production line. [ABSTRACT FROM AUTHOR]

More frequent global warming events, biological disasters, and anthropogenic activities have caused extensive damage to coral reefs around the world. Coral reefs in the Xisha Islands (also known as the Paracel Islands) have been damaged following rounds of heatwaves and crown-of-thorns starfish (CoTS) outbreaks over recent decades. Based on a comprehensive community survey in 2020, we determined a diagnosis for the present state of six coral regions in the Xisha Islands. The findings suggested that these regions had a total of 213 species of scleractinian corals belonging to 43 genera and 16 families. Living coral coverage across sites was widely divergent and ranged from 0.40% (IQR: 7.74-0.27%) in Panshi Yu to 38.20% (IQR: 43.00-35.90%) in Bei Jiao. Coral bleaching prevalence was 23.90% (IQR: 41.60-13.30%) overall and topped out at 49.30% (IQR: 50.60-48.10%) in Bei Jiao. Five of the coral regions (all but Yongxing Dao) were under threat of CoTS outbreaks. High mortality combined with excellent recruitment rates suggested potential rehabilitation after recent deterioration. We employed a quantifiable Deterioration Index (DI) to evaluate the intensity of deterioration of coral reefs in the Xisha Islands. The results showed that Yongxing Dao and Langhua Jiao had low recent deterioration (DIrecent = 0.05, IQR: 0.07-0.02 and 0.04, IQR: 0.11-0.01, respectively), while Bei Jiao, Yongle Atoll, Yuzhuo Jiao, and Panshi Yu had high recent deterioration (DIrecent > 0.16). Different monitoring sites within the same coral region were heterogeneous with regards to all above indexes. Moreover, we reviewed and discussed potential disturbances that threaten the health of the Xisha Islands' corals. It is crucial to identify severely afflicted areas and find successful methods to better manage coral reef health in this region. [ABSTRACT FROM AUTHOR]

• Alternative procedure for components TID radiation qualification. • Comparative analysis between gamma rays versus X-rays as TID radiation source. • Medical LINAC valid for a TID characterization as a radiation source of electronic components. Ionizing radiation can cause temporary or permanent failures in electronic components used in space applications. The characterization of these components and the design of on-board electronic systems that are tolerant and functional under these conditions are fundamental requirements in flight systems engineering. This paper presents experimental results from tests performed with 60 Co as gamma radiation source, comparing them with those results obtained with a medical LINAC (LINear ACcelerator) producing X-rays with similar energy. Following ESA ESCC-22900 standard it was shown that the results achieved with both radiations are equivalent, and therefore we prove that medical LINACs, that are much more easily accessible than 60 Co facilities, are suitable for testing electronic systems for space applications. [ABSTRACT FROM AUTHOR]

When performing remote tasks using robots in nuclear power plants, a 3D shape measurement system is advantageous in improving the efficiency of remote operations by easily identifying the current state of the target object for example, size, shape, and distance information. Nuclear power plants have high-radiation and underwater environments therefore the electronic parts that comprise 3D shape measurement systems are prone to degradation and thus cannot be used for a long period of time. Also, given the refraction caused by a medium change in the underwater environment, optical design constraints and calibration methods for them are required. The present study proposed a method for developing an underwater 3D shape measurement system with improved radiation tolerance, which is composed of commercial electric parts and a stereo camera while being capable of easily and readily correcting underwater refraction. In an effort to improve its radiation tolerance, the number of parts that are exposed to a radiation environment was minimized to include only necessary components, such as a line beam laser, a motor to rotate the line beam laser, and a stereo camera. Given that a signal processing circuit and control circuit of the camera is susceptible to radiation, an image sensor and lens of the camera were separated from its main body to improve radiation tolerance. The prototype developed in the present study was made of commercial electric parts, and thus it was possible to improve the overall radiation tolerance at a relatively low cost. Also, it was easy to manufacture because there are few constraints for optical design.

To keep up with the demands for smaller antennas with increased performance and decreased costs, most next-generation architectures mandate higher integrated circuit (IC) chip integration. Compared to conventional packaging configurations, advanced chip packaging technologies, such as 2.5D and 3D, offer greater chip compatibility and lower power consumption. Given these advantages, the adoption of advanced packaging is inevitable. Within advanced packaging, the copper pillar interconnect is a key enabling technology, and the next logical step. This technology offers several benefits, including improved electromigration resistance, improved electrical and thermal conductivity, simplified under bump metallization (UBM), and higher input/output (I/O) density. The fine pitches that copper pillars allow help the technology to supersede solder bump technology, which reaches its lowest pitch at around 40 microns. Finer pitches allow for a higher I/O count, which increases performance. In this work, the assembly of ultrathin monolithic microwave integrated circuit (MMIC) gallium nitride (GaN) fine-pitch copper pillar flip chip assemblies on high-density interposers was successfully demonstrated. Using the 150-mm pitch copper pillar flip chip, the assembly processes for both organic printed circuit board (PCB) and silicon interposers were evaluated, with both an electroless nickel immersion gold (ENIG) and eutectic tin-lead solder pad finish evaluated. For the 2D/2.5D/3D assembly process development, a standard in-house pick and place tool was used, followed by mass solder reflow, finished with an underfill for reliability test. The interconnect robustness was determined by die pull strengths, a flux stamping investigation, and cross sections. Complete reliability and qualification test data on GaN copper pillar flip chip 2D assembly was completed, including 700 temperature cycles and unbiased highly accelerated temperature/humidity stress test (UHAST). Adding copper pillar technology to GaN MMIC dice, integrating GaN Cu pillar technology into 2.5D/3D packaging technology, and assessing GaN Cu pillar interconnect reliability at the interposer level are all unique aspects of this work. [ABSTRACT FROM AUTHOR]