A Robust and Optimal Multidisciplinary Approach For Space Systems Conceptual Design

L'abstract è presente nell'allegato / the abstract is in the attachmen

-ilities Tradespace and Affordability Project – Phase 3

One of the key elements of the SERC’s research strategy is transforming the practice of systems engineering and associated management practices – “SE and Management Transformation (SEMT).” The Grand Challenge goal for SEMT is to transform the DoD community’s current systems engineering and management methods, processes, and tools (MPTs) and practices away from sequential, single stovepipe system, hardware-first, document-driven, point- solution, acquisition-oriented approaches; and toward concurrent, portfolio and enterprise- oriented, hardware-software-human engineered, model-driven, set-based, full life cycle approaches.This material is based upon work supported, in whole or in part, by the U.S. Department of Defense through the Office of the Assistant Secretary of Defense for Research and Engineering (ASD(R&E)) under Contract H98230-08- D-0171 (Task Order 0031, RT 046).This material is based upon work supported, in whole or in part, by the U.S. Department of Defense through the Office of the Assistant Secretary of Defense for Research and Engineering (ASD(R&E)) under Contract H98230-08- D-0171 (Task Order 0031, RT 046)

Tradespace and Affordability – Phase 2

MOTIVATION AND CONTEXT: One of the key elements of the SERC’s research strategy is transforming the practice of systems engineering – “SE Transformation.” The Grand Challenge goal for SE Transformation is to transform the DoD community’s current systems engineering and management methods, processes, and tools (MPTs) and practices away from sequential, single stovepipe system, hardware-first, outside-in, document-driven, point-solution, acquisition-oriented approaches; and toward concurrent, portfolio and enterprise-oriented, hardware-software-human engineered, balanced outside-in and inside-out, model-driven, set-based, full life cycle approaches.This material is based upon work supported, in whole or in part, by the U.S. Department of Defense through the Office of the Assistant Secretary of Defense for Research and Engineering (ASD(R&E)) under Contract H98230-08- D-0171 (Task Order 0031, RT 046).This material is based upon work supported, in whole or in part, by the U.S. Department of Defense through the Office of the Assistant Secretary of Defense for Research and Engineering (ASD(R&E)) under Contract H98230-08- D-0171 (Task Order 0031, RT 046)

Revisiting the Question: Are Systems of Systems just (traditional) Systems or are they a new class of Systems?

This paper revisits a question asked and debated widely over the past decade: are Systems of Systems (SoS) just traditional systems or are they a new class of systems? Many have argued that SoS are a new class of systems, but little research has been available to provide evidence of this. In this paper we share highlights of recent research to show SoS not only have a different structure than systems and thus need to be engineered differently, but also may possess different attributes for beyond first use properties (the “illities”) such as flexibility and adaptability as compared to systems. By examining historical examples and by using a maritime security SoS as a research test bed, this paper shows that the “ility” called survivability had some design strategies that were directly mapped from systems and also allowed new strategies that only made sense for a SoS (e.g. vigilance). The paper also shows that some design strategies have a different implementation and meaning (e.g. margin) at the level of a system compared to SoS level. We conclude the answer to the question “Are SoS’s just systems?” is both yes and no. They are manifestly systems but possess properties not found in traditional systems. This is shown to true of the meta-property of survivability as applied against a directed SoS

Space System Architecture

Final Report of SSPARC: the Space Systems, Policy, and Architecture Research Consortium (Thrust II and III)Sponsored jointly by the Lean Aerospace Initiative (LAI), US Air Force, and a consortium of aerospace companie

A framework for space systems architecting under stakeholder objectives ambiguity

Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2012.Cataloged from PDF version of thesis.Includes bibliographical references (p. 238-251).Matching high ambitions with scarce resources is one of the primary challenges of the aerospace industry, on par with the technical challenges of developing new technology. The challenge is further complicated in space exploration, by its own nature aimed at exploring the unknown. Stakeholder objectives are often unclear due to business cases highly exploratory in nature. Further ambiguity emerges from disagreement between stakeholders and decision-makers called to formulate scientific, technological and policy requirements for new systems. This thesis develops a structured approach to develop recommendations to system architects concerned with the design of unprecedented large aerospace infrastructures for which objectives are ambiguous or unclear. The approach is composed of three parts. The first part consists in a novel taxonomy of ambiguity in systems design that classifies ambiguities in reducible and irreducible components. Building on this taxonomy, the second part of this thesis develops a Descriptive Systems Architecting Management Framework (SA-MF) to distill canonical forms of ambiguity management from the literature in political science, finance and economics, management, and engineering design. The third part of the dissertation presents a Delphi-Based Systems Architecting Framework (DB-SAF). DB-SAF objectives are to identify sources of ambiguity in the value delivery and tradespace exploration processes, characterize and model sources of ambiguity, mitigate ambiguities through effective systems architecting strategies, integrate the analysis of upstream and downstream architecting processes, and to assess the impact of requirement ambiguities on the architectural tradespace. The proposed systems architecting approach has been applied to three case studies: the assessment of a robotic Mars Sample Return Campaign, the study of in-space transportation infrastructure for future human space exploration beyond Low Earth Orbit, and the retrospective analysis of satellite constellations for commercial applications. The application of the proposed approach to three different disciplinary fields demonstrates its broad applicability for architecting complex aerospace systems. This dissertation integrates methods from systems engineering, systems architecting, multivariate statistical analysis, uncertainty modeling, economics, management science and social science research. It allows decision-makers to visualize an architectural synthesis of aerospace systems, understanding adverse impacts of ambiguity, and supporting negotiations among stakeholders for efficient compromise in systems architecting.by Alessandro Aliakbargolkar.Ph.D

Empirically characterizing evolvability and changeability in engineering systems

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2012."June 2012." Cataloged from PDF version of thesis.Includes bibliographical references (p. 205-212).The beginning phases of system development and conceptual design require careful consideration, as these decisions will have significant influence on system lifetime performance and are often made with incomplete system knowledge. Decision makers may improve their capacity to discriminate between system concepts and design choices by measuring a system's "ilities" such as changeability, evolvability, and survivability. These ilities may enable systems to respond to perturbations in the design space, context space, and needs space in order to ensure system functionality and adequate performance over time. A system may be designed to change in response to perturbations, or remain statically robust/survivable to perturbations in order to avoid deficiencies or failures. This research attempts to analyze the mechanisms that allow system changes to occur. More specifically, this research will further the characterization of system changeability and evolvability and ultimately provide a structured and meaningful way of classifying system characteristics often described as "ilities". Value sustainment is proposed as an ultimate goal of systems, providing value in spite of perturbations in design, context, or needs. The premise of value sustainment is investigated through four distinct research thrusts: 1) a basis for defining system changes and ilities; 2) a system change examples database with categorical cluster analysis case research; 3) epoch-shift, impact, response, outcome case research; and 4) expert interviews case research. Focusing on change-related ilities, this research proposes constructs for identifying and enabling vague, yet desirable, system properties. Evolvability is characterized as a subset of changeability and defined as the ability of an architecture to be inherited and changed across generations [over time], with a set of ten proposed design principles including decentralization, redundancy, targeted modularity, scalability, integrability, reconfigurability, mimicry, leverage ancestry, disruptive architectural overhaul, and resourceful exaptation.by Jay Clark Beesemyer, Jr.S.M

Life Cycle Evaluation under Uncertain Environmental Policies Using a Ship-Centric Markov Decision Process Framework.

A novel design evaluation framework is offered to improve early stage design decisions relating to environmental policy change and similar non-technical disturbances. The goal of this research is to overcome the traditional treatment of policy as a static, external constraint and to address in early stage design the potential disruptions to performance posed by regulatory policy change. While a designer’s primary purpose is not to affect policy, it is the responsibility of the designer to be cognizant of how policy can change, of how to assess the implications of a policy change, and of how to deliver performance despite change. This research addresses a present need for a rigorous means to keep strategic pace with policy evolution. Use of a Markov Decision Process (MDP) framework serves as a unifying foundation for incorporating temporal activities into early stage design considerations. The framework employs probabilistic methods via a state-based structure to holistically address policy uncertainty. Presented research enables exploration of the performance of a design solution through time in the face of environmental instabilities and identifies decisions necessary to negotiate path dependencies. The outcome of this research is an advanced framework for addressing life cycle management needs that arise due to policy change, as judged from a life cycle cost perspective. Original metrics for evaluating decision paths provide insight into how the timing, location, and confluence of disturbances impact design decisions. Development of the metrics is driven by a desire to communicate the design-specific characteristics of a strategic response to policy change. Quantifying the amount and type of uncertainty present, changeability afforded, and life cycle changes exercised offer points of comparison among individual design solutions. The knowledge gained from path-centric measurements enables an enhanced ability to characterize design lock-in. Principles and metrics borne out of the design evaluation framework are validated through two ship design examples related to ballast water treatment and carbon emissions.PHDNaval Architecture & Marine EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/96130/1/ndniese_1.pd

A conceptual system design and managerial complexity competency model

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Complex adaptive systems are usually difficult to design and control. There are several particular methods for coping with complexity, but there is no general approach to build complex adaptive systems. The challenges of designing complex adaptive systems in a highly dynamic world drive the need for anticipatory capacity within engineering organizations, with a goal of enabling the design of systems that can cope with an unpredictable environment. This thesis explores this question of enhancing anticipatory capacity through the study of a complex adaptive system design methodology and complexity management competencies. A general introduction to challenges and issues in complex adaptive systems design is given, since a good understanding of the industrial context is considered necessary in order to avoid oversimplification of the problem, neglecting certain important factors and being unaware of important influences and relationships. In addition, a general introduction to complex thinking is given, since designing complex adaptive systems requires a non-classical thought, while practical notions of complexity theory and design are put forward. Building on these, the research proposes a Complex Systems Life-Cycle Understanding and Design (CXLUD) methodology to aid system architects and engineers in the design and control of complex adaptive systems. Starting from a creative anticipation construct - a loosening mechanism to allow for more options to be considered, the methodology proposes a conceptual framework and a series of stages to follow to find proper mechanisms that will promote elements to desired solutions by actively interacting among themselves. To illustrate the methodology, a financial systemic risks infrastructure systems architecture development case study is presented. The final part of this thesis develops a conceptual model to analyse managerial complexity competency model from a qualitative phenomenological study perspective. The model developed in this research is called Understanding-Perception-Action (UPA) managerial complexity competency model. The results of this competency model can be used to help ease project manager’s transition into complex adaptive projects, as well as serve as a foundation to launch qualitative and quantitative research into this area of project complexity management

Multiobjective Planning and Design of Distributed Stormwater Harvesting and Treatment Systems through Optimization and Visual Analytics

Stormwater harvesting (SWH) is an important water sensitive urban design (WSUD) approach that provides an alternate water source and/or improves runoff quality through stormwater best management practice technologies (BMPs). Through integrated SWH system design at the development scale practitioners must account for trade-offs between cost, harvested volume, and water quality improvement performance which are usually dependent on design decisions for the type, size, and spatial distribution of BMPs. In catchment management planning, additional objectives such as catchment vegetation improvement and public recreation benefit need to be maximized for a catchment region within a limited budget. As such, planning and design of SWH systems with distributed BMPs is a complex problem that requires optimal allocation of limited resources to maximize multiple benefits. In this thesis, two innovative formal optimization approaches are presented for formulating and identifying optimal solutions to problems requiring distributed BMPs. Firstly, a multiobjective optimization framework is presented and applied to a case study for the conceptual design of integrated systems of BMPs for stormwater harvesting. The aim of this work is to develop a conceptual design modelling framework that handles the optimal placement of stormwater harvesting (SWH) infrastructure within an urban development. The framework produces preliminary SWH system designs representing optimal trade-offs between cost, water harvesting, and water quality improvement measures. Secondly, a many (>3) -objective optimization framework is presented and applied to a case study for catchment planning requiring the selection of a portfolio of distributed BMP projects. The framework produces portfolios that are optimal with respect to four objectives, and enables exploration of the many-objective trade-off surface using interactive visual analytics. In addition, a multi-stakeholder method is presented, which enables catchment managers and local government authorities to identify solutions that represent a compromise between 16 objectives and eight optimization problem representations using interactive visual analytics to encourage a negotiated solution. This thesis contains one paper accepted in the Journal of Water Resources Planning and Management (Paper 1), and one paper submitted (Paper 2), and one paper to be submitted (Paper 3) to peer-reviewed journals in the field of water resources management.Thesis (Ph.D.) -- University of Adelaide, School of Civil, Environmental & Mining Engineering, 201