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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 paper investigates how different Hybrid Agile Product Development Process (hybrid PDP) architectures affect project performance in space hardware development. The performance benchmark of alternative hybrid Agile PDPs offers valuable information for structuring Minimum Viable Products in order to meet customer needs while improving effectiveness and efficiency of the PDP. We propose a modeling framework to simulate iterations through the product development process, and therefore optimize tasks definition in Agile frameworks while accounting for product interdependencies between components, subsystems and relevant lifecycle processes such as assembly, integration, testing, procurement, and validation. The framework has been verified on a case study of an undisclosed telecommunication payload hosted onboard a nanosatellite mission. The results provide an initial understanding of the applicability of Agile methods to the co-development of complex engineering systems based on experimental data (notably tasks, task durations, dependencies, and cost) that have been collected on the field as well as simulation outputs. The model we propose also represents an effective decision making support instrument to evaluate the programmatic and technical tradeoffs.

We present the preliminary results of our investigation on the effectiveness of the Serum methodology for Agile development of space hardware. We analyze the development process of a hardware payload that is part of a host nanosatellite mission composed of two 6U CubeSats (30cm x 20cm x 10cm). The host mission is a collaboration with several partners including academia and small and medium enterprises. Scrum is a product development process created as a faster, more effective way of developing software. The goal of our investigation is to understand whether and by how much the same Scrum principles that proved successful in software can be adopted vis-a-vis in hardware projects. We also intend to identify the fundamental challenges in such an approach for space missions. In the host mission, Scrum has been adopted for the development of the payload subject to the investigation. The paper introduces the ongoing development process and identifies Scrum-related challenges internal to the payload development and challenges related to the coordination of the process with partners adopting established development processes. The paper identifies opportunities of future work for the fine tuning of Agile development methodologies in space projects and illustrates key statistics that have been collected throughout the development so far.

In recent years, the engineering community realized the potential for additive manufacturing (AM) to be a game-changer in product development. Nevertheless, it is not yet possible to fully take advantage of this technology because it implies a different approach to engineering design. The dependencies of AM on related technologies, such as material modeling, design tools, computing, and process design represent a challenge for engineers. A comprehensive system engineering approach is needed to address the introduction of AM in new design projects. This article proposes a systems design approach to evaluate the use of AM in the development of new systems at the early stage of design. The methodology aims to provide a preliminary estimation of performance, cost, and time of parts manufactured using additive techniques. The article introduces a set of design drivers and criteria to standardize the design process and support the manufacturing technique decision-making process. The methodology is experimentally tested and validated by evaluating tradeoffs for two different case studies considering different engineering parameters. The analysis of the results shows a good consistency between framework predictions and experimental evidence, with an uncertainty level lower than 5%. The reliability of obtained results is discussed.

We present a survey conducted across industry, government agencies and academic organizations running concurrent design facilities for space applications, to analyze the differences in people management, tools, processes and facilities across many organizations using concurrent design. Our analysis is based on a literature review and structured interviews. Most organizations applying concurrent design also participate in related conferences and publish on their experiences with the approach. We collected data through a survey among subject matter experts involved in various roles in this type of concurrent design. The answers are evaluated quantitatively to allow a clear characterization of the state-of the-art. The data underpins common ideas about benefits and challenges of the concurrent design approach with data. We compiled statistics about minimal, typical and maximal team sizes, study duration, as well as size and critical features of facilities, and many more aspects. This review summarizes the learnings from concurrent design practice and describes open challenges to be addressed in future research.

Based on the intense technological environment requiring early and accurate analysis, this paper proposes competition based on figures of merit analysis in the context of technology planning and roadmapping. Competitive-based figures of merit are used in this context to benchmark the evolution of technology in an industrial sector while accounting for competitive forces, using a game-theoretical approach. The automotive industry is studied as a case of a highly competitive commercial enterprise. By the application of several tools for the preliminary analysis of the competition level, the competition-driven FOMs are distinguished.

Corporate research and technology (R&T) management needs reliable information for strategic planning. A commonly used tool are technology roadmaps, since they describe vision and corporate strategy for technology evolution. The process of creating a technology roadmap involves experts from engineering, product development and all support functions evaluating and comparing opportunities for incremental as well as disruptive innovation. This work describes an approach, where experts build and run models in a concurrent design environment allowing the evaluation of potential product architectures according to a defined set of figures of merit and at different time horizons. This mapping of the landscape can then inform the planning of technology investment and development. The process is illustrated using the example of a solar-electric aircraft technology roadmap.

Design methods for federated systems must consider local incentives and interactive effects among independent decision-makers. This paper extends value-centric design methodology (VCDM) to multi-actor cases using game theoretic principles. Federated systems can be represented as a Stag Hunt game where players choose between risk-dominant (non-cooperative) and payoff-dominant (cooperative) strategies. An independent strategy is a lower bound to federated value and a centralized strategy controlled by a federation authority is an upper bound under special cases. An application case considers a stylized system value model (SVM) of a federated satellite system (FSS) with two players and a tradespace of 530 symmetric design decisions. A federated concept with opportunistic, fixed-cost communication services demonstrates the effect of lower and upper bounds on system value. Risk in federated systems arises from misaligned strategies between players and can be quantitatively assessed with a subjective estimate of cooperation.

Novel distributed space mission concepts such as fractionation and federation promise to transform the design and operations approach of future missions. These paradigms require robust communications networking among other technologies. For the first time this paper explores the specifics of communications network protocols to enable Federated Satellite Systems using an opportunistic resource exchange frame open to all kinds of missions. Within satellite federations, participant spacecraft trade resources on a voluntary basis open to collaborative and/or commercial returns. The heterogeneous, mobile, flexible and scalable environment of satellite federations requires networking technologies capable of handling autonomous node discovery and frequent link disruptions. This work leverages existing Mobile Ad-Hoc Networking techniques to propose an FSS network protocol concept making use of OSLR neighbor sensing and store-carry-and-forward BATMAN routing concepts combined with link availability assessments and predictive topology routing. The performance of this protocol is tested through a dedicated network simulator and the FSS simulation toolkit. Results show the benefits of using FSS under this protocol. For a LEO-based scenario, average content delivery latency is improved from 41 minutes to 3.7 minutes by full usage of federated network benefits. Intermediate scenarios, such as 50% time network usage, present an average latency of 18 minutes. The paper ends by highlighting conclusions and next steps for the development of space communications protocols suitable for FSS.

Federated satellite systems (FSS) are a new class of space-based systems which emphasize a distributed architecture. New information exchanging functions among FSS members enable data transportation, storage, and processing as on-orbit services. As a system-of-systems, however there are significant technical and social barriers to designing a FSS. To mitigate these challenges, this paper develops a multi-stakeholder interactive simulation for use in future design activities. An FSS simulation interface is defined using the High Level Architecture to include orbital and surface assets and associated transmitters, receivers, and signals for communication. Sample simulators (federates) using World Wind and Orekit open source libraries are applied in a prototype simulation (federation). The application case studies a conceptual FSS using the International Space Station (ISS) as a service platform to serve Earth-observing customers in sun-synchronous orbits (SSO). Results identify emergent effects between FSS members including favorable ISS power conditions and potential service bottlenecks to serving SSO customers.

This paper presents an approach to optimize orbit geometries under satellite to satellite coverage criteria. The method described herewith is applicable to any space system concept featuring inter-satellite-links, including system concepts introducing links of opportunity between heterogeneous spacecraft at different orbits not designed a priori as a constellation. The latter is the case of federated satellite systems, that have recently been proposed as open satellite constellation concepts for opportunistic sharing of data relay and on board storage services. Federated satellite systems make use of unused telecommunications capacity available in participating spacecraft at any given time. This paper describes the satellite to satellite coverage optimization problem, a proposed optimization approach, and its analytical validation. The convergence of results is shown in terms of spatial discretization, temporal discretization and simulation period. The approach is demonstrated in a LEO to LEO network scenario, where orbital parameters of a single spacecraft are optimized to supply the maximum coverage to an example set of 6 LEO spacecraft, at different inter-satellite-link slant ranges. It is shown that increasing the inter-satellite-link maximum range above 6,000 km does not lead to further coverage benefits at LEO altitude. Orbit optimization for LEO coverage is also performed on a set of three spacecraft. In both cases, the optimum solutions feature polar inclination orbits, suggesting that said orbits may be advantageous for LEO satellite-to-satellite applications. This paper ends with conclusions outlining the future work on the satellite to satellite coverage optimization.