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Hardware developers started experimenting with Scrum to accelerate their product development. However, it is not possible to implement Scrum in the same way as it was done for software systems, where the approach is already well established. One of the processes required in Scrum is the estimate of task efforts when creating a backlog for an Agile Sprint. This article presents a pilot validation experiment of a novel Agile framework for the development of hardware systems, including a parametric tool to estimate task effort in a more rigorous way than traditional confidence votes. This article presents the validation of electronic hardware design task estimation and overall project performance. The validation is performed through experimental work with teams of junior engineering students. The validation experiment showed an improvement from a minimum of eight to a maximum of eighteen percent when employing the presented tool during planning phases of the development.

As small satellites are finding increased applicability in a number of space missions, the community is actively exploring the feasibility of missions employing active instruments on small spacecraft. In particular, synthetic aperture radars are of interest as they prove to be versatile tools for Earth Observation purposes. This paper proposes a trade space exploration model to identify designs for space-borne satellite synthetic aperture radars that address the desired instrument requirements. Two trade space analysis approaches are proposed, based on a multivariate analysis with two evaluation metrics and using parallel coordinate plots. The paper demonstrates the utility of the trade space model by considering two case studies. The first study looks at radar instruments on a broad range of small satellite platforms. This study narrows down a trade space of 1265 feasible radar designs to less than 44 Pareto optimal designs at different center frequencies (C- and X-band), elicits conditions for L-band SARs feasibility, and discusses the feasibility bounds and technical constraints on associated instrument and spacecraft requirements. The second study considers radars for 3U CubeSat platforms. The study identifies 44 Pareto optimal designs within 12,928 feasible designs and sheds light on the operational constraints required for the development of such innovative miniaturized radars.

A renewed interest in lunar exploration with the focus on establishing a constant human presence on the Moon calls for developing new lunar human landing systems (HLS) which would deliver the crew from the prospective Lunar Gateway station to the surface of the Moon and back. Over the years, different human lunar lander architectures were proposed and multiple architecture studies were performed. However, those studies are relevant to the specific assumptions and lunar architectures proposed at the time of conducting the study. Since the current vision for lunar exploration includes new features, such as having the Lunar Gateway and switching to reusable systems, there is a need for a new HLS architecture study. Such studies are being performed by private companies; however, those are rarely publicly available. The goal of this paper is to address this gap and provide a publicly available architectural analysis within the current views on the future human lunar exploration. We assume the Lunar Gateway in an L2 near rectilinear halo orbit and a landing site at the lunar South Pole; the number of HLS crew of 4; the surface stay time of ~7 days, the payload mass delivered to the surface of 500 kg, and the payload mass returned from the surface of 250 kg. A set of parametric models including an HLS model and an HLS program cost model is developed for the analysis. 39 architectures with varying number of stages (1, 2, and 3 stages) and propellant combinations (LOX/LH2, LOX/CH4, and MMH/NTO) are explored. The Pareto analysis shows that there is a difference between typical performance trends for expendable and reusable architectures. For expendable architectures, the 2-stage option seems to be the most advantageous while, for reusable architectures, the 1- and 3-stage options are either comparable or win over the 2-stage option even for the number of system uses as low as 3. In terms of the propellant combinations, pure LOX/LH2 or combined LOX/LH2/LOX/CH4 architectures dominate the tradespace. Assuming that the inter-stage propellant compatibility is a preferred option for systems refueling from the Gateway, 1-stage and 3-stage all LOX/LH2 architectures are identified as the likeliest candidates to have lowest HLS-related production and launch costs. Further cost analysis of those two architectures shows that the 1-stage HLS wins over the 3-stage system in terms of the overall HLS program cost if a long-term exploration program (on the order of tens of missions) is assumed.

This article presents the results of an expert survey aimed at defining the concept of New Space. New Space is a blurry concept which is oftentimes confused with other key ideas, such as the commercialization of space activities, or the use of miniaturized technology (such as CubeSats) in space missions design and implementation. Our expert survey reveals that the three key characteristics defining New Space are instead customer focus, new product development approaches, and new business models (private versus institutional investors). This article provides a semi-quantitative comparison of these characteristics, which we define as traits, which are used to distinguish between New Space and legacy space activities. Based on the results of the comparison and literature search, we provide a brief discussion of key technology trends emerging in New Space, namely, on autonomy, miniaturization, platforms, and crowd. This article will be of relevance to all stakeholders concerned with the creation and growth of New Space ecosystems worldwide, to which we propose ideas for taking different roles in the ecosystem.

A substantial body of literature on global design optimization techniques is based on an implicit assumption that a system under optimization is designed by a perfectly centralized design team with all team members committed to a global optimum solution. This assumption enables the system engineers to minimize all the objective functions simultaneously while controlling all design decisions at the same time. Recent research suggested that this inherent assumption may need to be revisited. This paper proposes a novel framework for design optimization using game theory, which represents a design process as a normal-form game and unifies two fundamental decisions of discipline designers, namely a system-global or a discipline-local optimum solution. This paper provides a general mathematical formulation of the framework for a design process with any number of discipline designers. The framework introduces the notion of the Nash front, which is a set of design solutions consisting of the Nash equilibria derived through the reallocation of design authority between discipline designers. This paper then tests the framework on a numerical optimization case study of a Stirling micro combined heat and power plant with two discipline designers. The result indicates that for the system capital cost and the system power output the difference between global Pareto-optimum designs and the Nash front designs on average across five different scenarios of design authority allocation was 22% and 16%, correspondingly. The application of the novel framework in different fields of engineering could help to build models that are more realistic and prevent impractical technical objectives.

This article analyzes venture capital (VC) investments in the Earth observation (EO) industry, with the aim of identifying technology trends. We collected tech- and investment-related publicly available data on all private, nonsubsidiary companies using their own satellite constellation or other EO instruments as needed to solve the problem of remote sensing of Earth's surface in the optical part of the electromagnetic spectrum and that were attracting investment and announcing plans for the future, as of 31 December 2016. We refer to these companies as EO startups. In the final sample, there are nine EO start-ups and 21 instruments used in their missions.

2021 IEEE International Geoscience and Remote Sensing Symposium (IGARSS), 11-16 July 2021, Brussels, Belgium, FSSCat, the “Federated Satellite Systems/ 3 Cat-5” mission was the winner of the 2017 ESA S^3 (Sentinel Small Satellite) Challenge and overall winner of the Copernicus Masters competition. FSSCat consists of two 6 unit cubesats carrying on board UPC's Flexible Microwave Payload - 2 (FMPL-2), an L-band microwave radiometer and GNSS-Reflectometer implemented in a software defined radio, and Cosine's HyperScout-2 visible and near infrared + thermal infrared hyperspectral imager, enhanced with PhiSat-1, a on board Artificial intelligence experiment for cloud detection. Both spacecrafts include optical and UHF inter-satellite links technology demonstrators, provided by Golbriak Space and UPC, respectively. This paper describes the mission, and the main scientific results of the FMPL-2 obtained during the first three months of the mission, notably the sea ice concentration and thickness, and the downscaled soil moisture products over the Northern hemisphere

With recent advances in technologies, deep learning is being applied more and more to different tasks. In particular, point cloud processing and classification have been studied for a while now, with various methods developed. Some of the available classification approaches are based on specific data source, like LiDAR, while others are focused on specific scenarios, like indoor. A general major issue is the computational efficiency (in terms of power consumption, memory requirement, and training/inference time). In this study, we propose an efficient framework (named TONIC) that can work with any kind of aerial data source (LiDAR or photogrammetry) and does not require high computational power while achieving accuracy on par with the current state of the art methods. We also test our framework for its generalization ability, showing capabilities to learn from one dataset and predict on unseen aerial scenarios.

This chapter overviews the key mission concepts associated with distributed CubeSat missions and outlines technical challenges entailed for key-related technical domains. Distributed CubeSat systems are mission architectures enabling new functionalities for CubeSat systems and providing design strategies to complement or enhance missions employing larger satellite platforms through interoperability. The chapter provides a brief description of the concepts of clusters, constellations, fractions, federations, series, swarms, and trains. It provides an overview of enabling technologies associated to distributed CubeSat systems. While most of these concepts have not yet been demonstrated in orbit with CubeSat systems, they are certainly an area of interest for further consideration in the development of future CubeSat platforms. This chapter aims at providing a broad overview and understanding of opportunities and key technical challenges associated with distributed CubeSat systems.

Nowadays, constellations and distributed networks of satellites are emerging as clear development trends in the space system market to enable augmentation, enhancement, and possibilities of new applications for future Earth Observation (EO) missions. While the adoption of these satellite architectures is gaining momentum for the attaining of ever more stringent application requirements and stakeholder needs, the efforts to analyze their benefits and suitability, and to assess their impact for future programmes remains as an open challenge to the EO community. In this context, this paper presents the mission and system architecture conceived during the Horizon 2020 ONION project, a European Union research activity that proposes a systematic approach to the optimization of EO space infrastructures. In particular, ONION addressed the design of complementary assets that progressively supplement current programs and took part in the exploration of needs and implementation of architectures for the Copernicus Space Component for EO. Among several use cases considered, the ONION project focused on proposing system architectures to provide improved revisit time, data latency and image resolution for a demanding application scenario of interest: Marine Weather Forecast (MWF). A set of promising system architectures has been subject of a comprehensive assessment, based on mission analysis expertise and detailed simulation for evaluating several key parameters such as revisit time and data latency of each measurement of interest, on-board memory evolution and power budget of each satellite of the constellation, ground station contacts and inter-satellite links. The architectures are built with several heterogeneous satellite nodes distributed in different orbital planes. Each platform can embark different instrument sets, which provide the required measurements for each use case. A detailed mission analysis has then been performed to the selected architecture for the MWF use case, including a refined data flow analysis to optimize system resources; a refined power budget analysis; a delta-V and a fuel budget analysis considering all the possible phases of the mission. This includes from the correction of launcher injection errors and acquisition of nominal satellite position inside the constellation, orbit maintenance to control altitude, collision avoidance to avoid collision with space debris objects and end-of-life (EOL) disposal to comply with EOL guidelines. The relevance of the system architecture selected for the MWF has been evaluated for three use cases of interest (Arctic sea-ice monitoring, maritime fishery pressure and aquaculture, agricultural hydric stress) to show the versatility and the feasibility of the chosen architecture to be adapted for other EO applications., This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 687490.

System prototypes and technology demonstrators are usually designed for one-time manufacturing. Issues related to later phases of the lifecycle start to appear when prototypes are consolidated into a product baseline. It is, therefore, beneficial for systems engineers to account for later phases of the project starting from its early stages, such as concept design and evaluation. We present a quantitative methodology with human decision-makers in the loop based on the design for manufacturing considerations, to support systems engineers in bridging the gap between the design phase and later phases of the lifecycle of the development of a complex system. The developed methodology consists of three phases main stages: “product definition and production context identification,” “design alternatives investigation,” and “analysis,” considering critical manufacturing phases and parameters. This paper demonstrates the proposed methodology on a case study of the design of a medical device for wheelchair support. Our approach allowed us to reduce the cost and time of production by 18.3 and 16.8 percent, respectively, by identifying areas of improvement of the design that accounted for manufacturing and assembly considerations. In the paper, we discuss the advantages and limitations of our approach and identify possibilities for future work in the area.

This work addresses a critical topic in federated satellites development: the lack of trust between stakeholders that would prevent any stakeholder joining a satellite federation owned and operated by multiple parties. A characterisation of security needs for federated satellite systems is proposed, showing that in order for a federation to offer an environment for a beneficial cooperation, a notion of identity, both user identity and data authentication, has to be introduced, and stakeholders' security requirements have to be satisfied. This paper presents a public key infrastructure (PKI) based protocol for addressing stakeholders' security requirements and ensuring data authentication, integrity and confidentiality in data transfer operations within satellite federations. The performance and cost overheads of the proposed security protocol are first characterised with an experimental implementation on a Raspberry Pi 2 platform, used as a representative proxy testbed of commercial off-the-shelf avionics for small satellites, and then with a benchmark on a range of CPUs to analyse which platforms achieve set performance goals with radio-based and laser-based communications. Recommendations for implementing security mechanisms in federated satellite systems are thus derived.