Framing Sustainability in Human-Centered Product Design

Engineers today have access to a myriad of tools for developing sustainable products that have minimal environmental impact. Although consumer interest in sustainability is increasing, it is still not foremost on the minds of many consumers. Engineers are thus faced with the dilemma of developing sustainable solutions for consumers who may not yet want or be able to articulate sustainability needs. We explore this issue by examining user research conducted by students in a graduate-level product design course. We present findings on how users define and describe sustainability, how sustainability needs interact with other user needs, and what tradeoffs people make and feelings people have when faced with sustainability trade-offs. We present a case study of one design team’s findings about sustainability, and how those findings affected the formulation of the team’s mission statement and product strategy. Based on these results, we propose recommendations for how to facilitate the design of innovative and sustainable consumer products.

A Framework for Engineering Dissection Exercise Creation and Implementation

Hands-on product dissection and reverse engineering exercises have been shown to have a positive impact on engineering education, and many universities have incorporated such exercises in their curriculum. The CIBER-U project seeks to examine the potential to utilize cyberinfrastructure to enhance these active-learning exercises. We have formulated a framework for product dissection and reverse engineering activity creation to support a more rigorous approach to assessing other exercises for satisfaction of the CIBER-U project goals and adapting the best practices. This framework is driven by the fulfillment of learning outcomes and considers the maturity of students at different levels. Prototype exercises developed with the framework are presented. The approach is sufficiently general that it can be applied to the consideration and adaption of other types of exercises while ensuring satisfaction of the established goals.

Some Ontological Distinctions of Function Based on the Role Concept

Function is an important aspect of artifacts in engineering design. Although many definitions of function have been proposed in the extensive research mainly in engineering design and philosophy, the relationship among them remains unclear. Aiming at a contribution to this problem, this paper investigates some ontological issues based on the role concept in ontological engineering. We discuss some ontological distinctions of function such as essentiality and actuality and then propose some fundamental kinds of function such as essential function and capacity function. Based on them, we categorize some existing definitions in the literature and clarify the relationship among them. Then, a model of function in a product life-cycle is proposed. It represents the changes of existence of the individuals of each kind of function, which are caused by designing, manufacturing and use. That model enables us to give answers to some ontological questions such as when and where a function exists and what a function depends on. The consideration on these issues provides engineers with some differentiated viewpoints for capturing functions and thus contributes to consistent functional modeling from a specific viewpoint. The clarified relationships among the kinds of function including the existing definitions in the literature will contribute to interoperability among functional models based on the different kinds and/or definitions.

Upper-Extremity Prostheses: A Renewed Approach

Upper-extremity (UE) prostheses are increasingly more functional and proportionately more costly, rendering them largely unattainable for impoverished amputees in the United States (US) and abroad. Recognizing the increasing need for appropriate devices, PhysioNetics, LLC is developing a heavy-duty, transradial body-powered (BP) UE prosthesis which can be prescribed with minimal instruction. The design of the key components, the split-hook terminal device [TD] and universal adjustable interface is presented in this paper. The TD is primarily fabricated from plastics to eliminate galvanic corrosion in saltwater environments, weighs 5.4 oz (153 g) and uses inexpensive rubber bands to generate pinch force. Unique gripping contours provide versatile grasp and replicate five (5) prehension patterns while six (6) discrete force settings provide 2 – 17 lbf (8.9 – 76 N) of pinch. Three (3) universal interface sizes (small, medium, and large) accommodate most amputees and comfortably support axial loads up to 40 lbf (178 N). Estimated manufacturing cost for a complete unit is less than US$250. Field testers report lower but comparable comfort to their individually custom-fabricated interfaces, and are highly satisfied with fit and function of the prosthesis overall. Ongoing development includes reduction of manufacturing costs, increasing interface comfort and implementing task-specific variant designs.

Application of Failure Modes and Effects Analysis to Support Product In-Use Information Feedback

Due to their increasing responsibility for the total lifecycle costs associated with their products, manufacturers are investing increasingly more efforts in their reduction. One way in which this can be achieved is through the elimination at the design stage of possible in-service issues. This can be supported through the feedback of product in-use information obtained from testing, prototyping and in-service lifecycle stages towards the earlier stages of the development process. In order to facilitate the feedback of this information to design, the idea of complimentary product structures is introduced. The relationships between these structures provide a link between product information across the various lifecycle stages. The similarities between the product structure and the FMEA structure are also examined. As the FMEA organizes its information on a component basis, it is suggested that it provides an adequate basis for the organization of the product in-use information in order to facilitate its association with the product structure. Based on these ideas, a full framework for the feedback and reuse of product in-use information is described.

The Study of the Interaction of Humans With Wheelchairs to Improve the Design

In order to evaluate a wheelchair design it is necessary to look at the capabilities of the user and the chair’s intended purpose. Whilst some chairs are only required to provide infrequent mobility indoors, others need to enable the user to travel great distances out doors over rough terrain. In this respect the chair should be considered in the same manner as any other ‘inclusive’ product (or be useable by all). There is a need to better understand the capabilities of different users and how this affects their ability to use a wheelchair for the express purpose required. A detailed experimental investigation was carried out into the wheelchair propulsion characteristics of people with paraplegia and tetraplegia. In this investigation, subjects’ posture, applied forces, and their strategies in applying forces to the wheel rims were studied. Three distinct postures and corresponding techniques were observed and subsequently modelled in a constraint-modelling environment. Here rules were developed that allowed these differing postures to be applied to a manikin representation and their effect upon the wheelchair mobility evaluated. From this study the needs for these classes of individuals were identified in order to allow the wheelchairs to be evaluated. Where conflicts existed between the chair and the user, different modifications in both chair and posture were proposed and assessed. Where no simple modifications exist such a study can provide the basis for a more radical and improved design.

UAS Mission Path Planning System (MPPS) Using Hybrid-Game Coupled to Multi-Objective Optimiser

This paper presents the application of advanced optimization techniques to Unmanned Aerial Systems (UAS) Mission Path Planning System (MPPS) using Multi-Objective Evolutionary Algorithms (MOEAs). Two types of multi-objective optimizers are compared; the MOEA Non-dominated Sorting Genetic Algorithms II (NSGA-II) and a Hybrid Game strategy are implemented to produce a set of optimal collision-free trajectories in three-dimensional environment. The resulting trajectories on a three-dimension terrain are collision-free and are represented by using Be´zier spline curves from start position to target and then target to start position or different position with altitude constraints. The efficiency of the two optimization methods is compared in terms of computational cost and design quality. Numerical results show the benefits of adding a Hybrid-Game strategy to a MOEA and for a MPPS.

Tools for Project-Based Active Learning of Amorphous Systems Design: Scenario Prototyping and Cross Team Peer Evaluation

Whereas team project-based learning of engineering design has attracted wide acceptance, it is still rare to see a curriculum that addresses high level societal needs involving diverse students with a wide range of practical experience. Such a curriculum should develop a shared understanding of the use of scenarios for amorphous products and a process to objectively evaluate the project progress while the design concepts mature. This paper describes two key tools that respond to these challenges: 1) scenario prototyping and 2) cross-team project scorecarding. These tools evolved through a collaborative curriculum development of Keio University, MIT, and Stanford in the development of the Active Learning Project Sequence (ALPS), a capstone experience for Keio’s new Graduate School of System Design and Management (SDM). ALPS selected a theme from the “Voice of Society,” according to which the project teams generated solution scenarios, identified requirements, and described the proposed system using appropriate prototypes of not only hardware but other amorphous means as well. The twelve ALPS teams in 2008 addressed the theme “Enhancing the Lives of Seniors in Japan,” which led to more specific scenarios. The paper gives an overview of the ALPS workshop sequence, and describes in detail two key learning modules that were essential in integrating the multi-disciplinary teams: a) scenario prototyping and b) cross-team project scorecarding. These methods are going through further trials in Stanford’s own Design for Manufacturability curriculum involving 10 project teams in the US and Japan.

DSM-Based Product Representation for Retirement Process-Based Modularity

Researchers have expanded the definition of product modularity from function-based modularity to life-cycle process-based modularity. In parallel, measures of product modularity have been developed as well as corresponding modular product design methods. However, a correct modularity measure and modular design method are not enough to realize modular product design. To apply the measure and design method correctly, product representation becomes an important aspect of modular design and imperative for realizing the promised cost savings of modularity. In this paper, a representation for retirement process-based modular design has been developed. Built upon previous representations for assembly and manufacturing-based product design, the representation includes a process similarity matrix and a process dependency matrix. The retirement process-based similarity is based on the similarity in components’ post-life intents (recycling, reuse, disposal), and either the degree of their material compatibility if the components will be recycled, or their disassembly direction or disassembly tools if they need to be disassembled from each other for retirement. Process similarity within a module leads to increased process efficiency (the elimination of non-value added tasks) from the sharing of tooling/equipment. Retirement process-based dependency is developed based on disassembly difficulty, one aspect of the physical interactions between components. Retiring components together as a module to eliminate disassembly and differential processing and reducing the disassembly difficulty between the modules can increase the efficiency of the retirement process. We have first presented which process elements we should consider for defining retirement process similarity and dependency, and then constructed the respective similarity and dependency factors tables. These tables include similarity and dependency factors, which, along with their quantifications, are used to determine a product’s modular architecture to facilitate the retirement process. Finally, a fishing reel is used to illustrate how to apply these factors tables to generate the similarity and dependency matrices that represent a product for retirement-process based modular design. Using these representations as input to the DSM-based modular design methods, we can achieve a design with a modular architecture that improves the retirement process efficiency and reduces retirement costs.

Gaming and Interactive Visualization for Education: A Multi-Disciplinary and Multi-University Collaborative Project

Most people are more perceptive to the geometric rather than the symbolic representation of information. In engineering disciplines, visualization combined with game characteristics can provide an essential mode to facilitate students’ understanding of important and abstract concepts, and improve students’ willingness to learn. In this project, game characteristics are introduced into course module design, but different from commercially available games in that the level of the contents and assessment tools in this project are meaningful to teachers, students, and parents. This paper focuses on the design of the Gaming and Interactive Visualization for Education system. Specifically, some initial design results from the three universities for three different courses plus the development of evaluation system will be presented. The system is expected to (1) offer interactions with gaming scenarios that can excite emotions, (2) provide an engaging learning experience of understanding engineering concepts by allowing students to visualize and interact with 3-D objects in a game scenario, (3) employ situated learning by exposing students to the type of challenges they will face in industry, and (4) fit better with the learning styles of the majority of engineering students.