Tradespace Exploration Research Articles

11.1.1 Using Natural Value‐Centric Time Scales for Conceptualizing System Timelines through Epoch‐Era Analysis

AbstractA traditional approach to system design is to optimize the system with regard to a set of system objectives, as defined in a given context. This approach falls short when designing systems that are capable of delivering sustained value to stakeholders in the face of a rapidly changing world. In order to achieve this value robustness, systems should be designed using natural value‐centric time scales, as defined by their contexts, for conceptualizing system timelines. Epoch‐Era Analysis is an approach that provides for visualization and a structured way to think about the temporal system value environment. This paper discusses Epoch‐Era Analysis as central to a tradespace exploration process for system design comparison and selection, invoking passive or active value robustness design strategies. The analysis can also serve as a socio‐technical bridge, integrating the tradespace exploration activities of architects and engineers, which may be traditionally independent efforts in contemporary engineering programs.

11.4.3 The Tradespace Exploration Paradigm

AbstractOver the past five years, researchers working on a number of system design projects in the Space Systems, Policy, and Architecture Research Consortium (SSPARC) at the Massachusetts Institute of Technology (MIT) have developed a process of value‐focused, broad tradespace exploration for the development of space systems. The broad tradespace framework has provided insights into communicating and quantifying the impact of changing requirements, uncertainty, and system properties such as flexibility and robustness. Additionally, insights have been made in applications to more complex cases, such as analyzing policy effects on system cost and performance, as well as understanding the time‐dependent effects of architecture and design choices for spiral development. The tradespace exploration paradigm both broadens the perspective of designers in conceptual design to better understand the “physics” of the proposed solutions relative to one another, and focuses the designer on delivering systems of value to key system stakeholders.

Multi-Attribute Tradespace Exploration as Front End for Effective Space System Design

Covers advancements in spacecraft and tactical and strategic missile systems, including subsystem design and application, mission design and analysis, materials and structures, developments in space sciences, space processing and manufacturing, space operations, and applications of space technologies to other fields.

New Methods for Rapid Architecture Selection and Conceptual Design

New methods for rapid front-end development of complex systems are introduced. New tradespace exploration techniques, advances in integrated concurrent engineering, and application of risk analysis methods early in the design process allow rapid progress from poorly defined user needs to fairly detailed conceptual designs. An overview is provided of the methods. A process is described that allows thousands of system architecture alternatives to be quickly and quantitatively assessed vs user needs. The result is an understanding of the tradespace, including its key constraints and sensitivities, as well as an optimum architecture. This architecture is used to specify needs for space vehicles, which are designed using integrated concurrent engineering techniques. Research in risk and uncertainty, policy impacts, and information technology methods allows quantitative consideration of these factors, resulting in designs that are robust to uncertainties and policy impacts and potentially more versatile and flexible. Eight systems designed to date using the method are briefly reviewed. Key literature and a number of companion papers that go into depth on various aspects of the method are cited.

A Knowledge Based Approach to Facilitate Enginering Design

This paper presents a knowledge-based approach to facilitate the engineering design process relating to spacecrafts. Because the design evolves over a long time and typically involves individuals working at different locations and frequently for different organizations, the degree of collaboration across temporal and spatial boundaries plays a major role in determining the aggregate time and cost involved in each instance of spacecraft design. A major aspect of such collaboration is the issue of communications - the ability to clearly and efficiently explicate and record the detailed needs of every stakeholder in the process, as well as the major design decisions and the rationale behind these decisions. The approach described in this paper provides a framework for facilitating the decision-making process in engineering design, by eliciting and capturing the goals and requirements of every stakeholder in the design process through utility and expense functions. An interactive system has been designed that incorporates a four faceted knowledge-based framework of knowledge acquisition, knowledge discovery, knowledge management and knowledge dissemination to provide designers and stakeholders with the capability to develop an evolving knowledge repository about all aspects of the design process. This interactive system includes the ability to capture succeeding versions of the detailed design, with zero or minimal human involvement; the capability is provided by a set of algorithms collectively named as SSPARCy. A complimentary tool, called MIST, facilitates the Multi-Attribute Tradespace Exploration process by enabling stakeholders to express their goals and preferences in a formalized manner. The combination of MIST and SSPARCy paradigms enables one to transform crucial applications that are today contingent on geographical proximity to occur with equal or superior effectiveness in a virtual world. While this paper analyzes a situation involving engineering design of spacecrafts, the proposed knowledge-based approach can be readily adopted to facilitate other applications that involve sustained collaboration across geographic and corporate boundaries.