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The complexity of many large-scale systems is outpacing our ability to effectively design, analyze, and manage such systems. Projects such as the F-35 Joint Strike Fighter, the Boeing Dreamliner, the Mars Science Lab, Boston’s Big Dig, and the U.S. Navy’s Independence warship have all been well over budget and behind schedule. While there may be a number of contributing factors, the enormous complexity of the designed systems is certainly a culprit. Large enterprises appear to be embarking on the design of such systems without a fundamental understanding of some critical principles of complex systems. These principles are emerging in the design research community and clearly illustrate that there are some elegant and simple principles that can be used to better understand, predict, and design large-scale complex systems. In this article, a number of these principles are presented in an effort to highlight the emerging research in the science of designing complex systems. An assertion is made that simplicity and complexity can and should co-exist and if simple and elegant principles are ignored, disastrous consequence may await. [ABSTRACT FROM AUTHOR]

A critical task in product design is mapping information from consumer to design space. Currently, this process largely depends on designers identifying and mapping psychological and consumer level factors to engineered attributes. In this way, current methodologies lack provision to test a designer's cognitive reasoning and could introduce bias when mapping from consumer to design space. In addition, current dominant frameworks do not include user-product interaction data in design decision making, nor do they assist designers in understanding why a consumer has a particular perception about a product. This paper proposes a framework--cyber-empathic (CE) design--where user-product interaction data are acquired using embedded sensors. To gain insight into consumer perceptions relative to product features, a network of psychological constructs is utilized. Structural equation modeling (SEM) is used as the parameter estimation and hypothesis testing technique, making the framework falsifiable in nature. To demonstrate effectiveness of the framework, a case study of sensor-integrated shoes is presented, where two models are compared--one survey-only and one using the cyber-empathic framework model. Covariance-based SEM (CB-SEM) is used to estimate the parameters and the fit indices. It is shown that the cyber-empathic framework results in improved fit over a survey-only SEM. This work demonstrates how low-level user-product interaction data can be used to understand and model user perceptions in a way that can support falsifiable design inference. [ABSTRACT FROM AUTHOR]

This paper discusses the design and development of a motion-based driving simulation and its integration into driving simulation research. The integration of the simulation environment into a road vehicle dynamics curriculum is also presented. The simulation environment provides an immersive experience to conduct a wide range of research on driving behavior, vehicle design and intelligent traffic systems. From an education perspective, the environment is designed to promote hands-on student participation in real-world engineering experiences that enhance conventional learning mechanisms for road vehicle dynamics and engineering systems analysis. The paper assesses the impact of the environment on student learning objectives in an upper level vehicle dynamics course and presents results from research involving teenage drivers. The paper presents an integrated framework for the use of real-time simulation and large-scale visualization to both study driving behaviors and to discover the impact that design decisions have on vehicle design using a realistic simulated driving interface. [ABSTRACT FROM AUTHOR]

The design of large scale complex engineering systems requires interaction and communication between multiple disciplines and decentralized subsystems. Game theory has been used previously to model interactions between distributed multidisciplinary design subsystems and predict convergence and equilibrium solutions. These game theoretic models assume that designers make perfectly rational decisions by selecting solutions from their rational reaction set. For convergent decentralized design problems, the intersection of the designers' rational reaction set results in a Nash equilibrium solution where designers may converge if they were making rational choices. However, this equilibrium solution is rarely optimal from a multi-objective optimization perspective. Further, empirical studies reject the claim that decision makers always make rational choices and the concept of bounded rationality is used to explain such behavior. In this paper, a framework is proposed that uses the idea of bounded rationality in conjunction with set-based design, metamodeling, and multi-objective optimization techniques to improve solutions for convergent decentralized design problems. Through the use of this framework convergent decentralized design problems converge to solutions that are superior to the Nash equilibrium. [ABSTRACT FROM AUTHOR]

Research on complex system optimization has focused on areas including algorithms, coordination strategies, and communication tools. This paper considers optimization from the perspective of information coordination during the solution process. This work aims to determine the potential impact of factors including the role of a system facilitator in managing system-level tradeoffs, the influence of an ideal information scenario, the choice of system variables, and the amount and form of passed information. The goal is not to develop the "best" communication structure or optimization algorithm, but to understand the significance of these factors. A traditional multidisciplinary design optimization coordination framework, a game theoretic approach, and a modified game theory approach are used to mimic design team behaviors. Results suggest these factors can influence the coordination process outcomes: The choice of system variable plays a significant role in the optimality of the final design; perfect information does not necessarily reduce the number of iterations or improve optimality; a system facilitator aids in making better design tradeoffs, though it is possible to achieve optimality without one; and the stability of the design cycle depends on the amount of passed information. This suggests a design team should carefully analyze the initial design space to determine an appropriate design formulation before applying optimization. [ABSTRACT FROM AUTHOR]

When developing an artifact, designers must first capture and represent user needs. These needs can then be transformed into system requirements or objectives. The contribution of this work is rooted in the formalization of the affordance-based approach for capturing user needs in the early stages of design. This formalization comes in three forms: the first affordance basis for engineering design (a defined set of affordances), a formal structure for affordance statements, and a new relational model structure. This formalization is intended to improve model quality and consistency, while managing model creation resources. Further, this affordance-based approach to capturing user needs imposes a level of abstraction that forces solution independence yet is capable of capturing the large range of user needs. As such, the approach provides a structured approach to problem abstraction-the process of specifying user needs without reference to specific solutions. This affordance-based problem representation relies on other design process tools to help develop the actual artifact, which is also discussed. [ABSTRACT FROM AUTHOR]

As college students enter engineering, they face challenges when they navigate across various transitions. These challenges impact whether a student can successfully adapt to the rigorous curricular requirements of an engineering degree and to the norms and expectations that are particular to engineering. This article focuses on the transitions between disciplinary literacies, primarily addressing how ideas are communicated and which types of semiotic representations are valued, required, and ignored by the different cultures that come into play both prior and during a student’s engineering education. Specifically, it addresses navigation:Across secondary to postsecondary institutional expectations, contrasting common curricular experiences of secondary students and postsecondary curricular expectations.Between and within disciplines (including mathematics and science), which often have different ways of communicating and representing a single concept, especially in theoretical applications and practical calculations.From the traditional pedagogies of classrooms to the different methods and expectations of laboratory settings (for example, collaborative engagement in planning, experimentation, an understanding of experimental error, and an understanding of how all three are communicated and represented). [ABSTRACT FROM PUBLISHER]

Teenage drivers diagnosed with attention-deficit/hyperactivity disorder (ADHD) are at significant risk for negative driving outcomes related to morbidity and mortality. However, there are few viable psychosocial treatments for teens with ADHD and none focus on the key functional area of driving. The Supporting the Effective Entry to the Roadway (STEER) program was evaluated in a clinical trial to investigate whether it improved family functioning as a proximal outcome and driving behavior as a distal outcome. Method: One hundred seventy-two teenagers with ADHD, combined type, were randomly assigned to STEER or a driver education driver practice program (DEDP). Results: Relative to parents in the DEDP condition, parents in STEER were observed to be less negative at posttreatment and 6-month follow-up but not at 12-month follow-up, and there were no significant differences for observed positive parenting. Relative to teens in the DEDP condition, teens in STEER reported lower levels of risky driving behaviors at posttreatment and 6-month follow-up, but not at 12-month follow-up. Groups did not differ on objective observations of risky driving or citations/accidents. Conclusions: The STEER program for novice drivers with ADHD was effective in reducing observations of negative parenting behavior and teen self-reports of risky driving relative to DEDP; groups did not significantly differ on observations of positive parenting or driving behaviors. [ABSTRACT FROM AUTHOR]

When developing a product, designers must decide what consumer variation will be addressed and how they will address it, because each consumer has a unique set of human factors, preferences, personal knowledge, and solution constraints. Numerous design methodologies exist to support the design of a product or set of products that address this consumer variation. However, currently there is little work supporting the selection of a design methodology, resulting in an ad hoc or a priori decision before conceptual design begins. This paper presents an affordance-based design method for use prior to conceptual design to help designers understand the consumer variation that is present. This facilitates the creation of a product or set of products that meets the demands of both the consumer(s) and the organization that is developing the product. Once consumer variation is understood, conceptual design can be performed with a more complete understanding of the overall problem. [ABSTRACT FROM AUTHOR]

The tower represents a significant portion of the materials and cost of the small wind turbine system. Optimization techniques typically maximize the tower loading capability while reducing material use and cost. Still, tower design focuses mainly on structural integrity and durability. Moreover, tower motion that intensifies drivetrain and structural loads is only rarely considered. The environmental impact of the wind turbine must also be considered since wind energy promotes sustainability. Trade-offs between the structural performance, cost, and environmental impact are examined to guide the designer toward a sustainable alternative. Ultimately, an optimal design technique can be implemented and used to automate tower design. In this study, nine tower designs with different materials and geometries are analyzed using finite element analysis (FEA). The optimal tower design is selected using a multilevel-decision-making procedure. The analysis suggests that steel towers of minimal wall thickness are preferred. This study is a continuation of the previous work that optimized energy production and component life of small wind systems (Hall et al., 2015, "An Integrated Control and Design Framework for Optimizing Energy Capture and Component Life for a Wind Turbine Variable Ratio Gearbox," ASME J. Sol. Energy Eng., 137(2), p. 021022). The long-term goal is to develop a tool that performs optimization and automated design of small wind systems. In our future work, the tower and drivetrain designs will be merged and studied using higher fidelity models. [ABSTRACT FROM AUTHOR]

Material selection significantly affects environmental impacts and other objectives of a product design. Life cycle assessment (LCA) methods are not efficient enough for use at the early design stages to prune a design space. Material properties consist of discrete data sets, which are further complicated when LCA data are included, thus posing a significant challenge in the construction of surrogate models for prediction of all relevant behaviours and numerical optimisation. In this work, we address the unique challenges of material selection in sustainable product design in some important ways. Salient features of the robust surrogate modelling approach include achieving manageable dimensionality of LCA with a minimal loss of the important information by the consolidation of significant factors into categorised groups, as well as subsequent efficiency enhancement by a streamlined process that avoids the construction of full LCA. This approach combines efficiency of use with a mathematically rigorous representation of any pertinent objectives across a design space. To this end, we adapt a two-stage sampling approach in surrogate model construction for sustainability considerations based on a feasible approximation of a Latin Hypercube design at the first stage. The development and implementation of the method are illustrated with the aid of an automotive disc brake design, and the results are discussed in the context of robust optimal material selection in early sustainable product design. [ABSTRACT FROM AUTHOR]

Objective: Youth with ADHD exhibit positive bias, an overestimation of ability, relative to external indicators. The positive bias construct is understudied in adolescents, particularly in the domain of driving. Study is needed as youth with ADHD experience greater negative outcomes in driving relative to typically developing teens., Method: Positive bias on a driving simulator task was investigated with 172 teenagers with ADHD, combined type. Youth participated in a driving simulation task and rated driving performance afterward., Results: Compared with external ratings of driving performance, youth overestimated driving competence for specific driving behaviors as well as globally. The global rating demonstrated a greater degree of positive bias. Greater positive bias on global ratings of driving ability also predicted greater rates of risky driving behaviors during the simulator exercise independent from disruptive behavior disorder symptoms., Conclusion: Results inform prevention and intervention efforts for teenage drivers with ADHD.