Prototype for X (PFX): A Prototyping Framework to Support Product Design

Open Access
- Author:
- Menold, Jessica D
- Graduate Program:
- Mechanical Engineering
- Degree:
- Doctor of Philosophy
- Document Type:
- Dissertation
- Date of Defense:
- February 17, 2017
- Committee Members:
- Kathryn Jablokow, Dissertation Advisor/Co-Advisor
Timothy Simpson, Committee Chair/Co-Chair
Scarlett Miller, Committee Member
Meg Small, Committee Member
Aaron Knochel, Outside Member
Timothy Simpson, Dissertation Advisor/Co-Advisor
Kathryn Jablokow, Committee Chair/Co-Chair - Keywords:
- Prototype
Design Theory and Methods
Human Centered Design
Design Thinking
Design For X - Abstract:
- Of the estimated 140 billion US dollars spent in new product development by large companies each year, around 40% is wasted on failed products. The largest sunk cost in new product development occurs during prototyping activities. We know prototyping activities are critical to the design process as they translate often fuzzy ideas into physical artefacts, support communication, enhance design development, and aid in decision-making. Engineering design research has failed to provide designers and engineers—practitioners as well as educators—with formal methods or approaches for prototyping to help reduce these losses and increase the likelihood of product success. Instead, designers and engineers must rely on experience, tacit knowledge, and individual judgment to navigate prototyping activities, often resulting in the inefficient use of resources and time. An extensive literature review of prototyping research and a study of novice designers’ perceptions of prototyping are used in this work to develop and validate a set of specifications for a holistic and structured prototyping framework. A novel framework to help structure prototyping, Prototype for X (PFX), is proposed as an alternative to traditional prototyping approaches in engineering design. The PFX framework is composed of three main phases: (1) Frame, (2) Build, and (3) Test. The phases of PFX help designers optimize resources to build prototypes that test core assumptions and inform the design and development new products. Similar to the “illities” in Design for X, PFX uses lenses to structure and scaffold the prototyping process to make improvements in specific areas. In order to validate the PFX framework, in this work we study the effects of three lenses, namely, Prototype for Desirability, Prototype for Feasibility, and Prototype for Viability. These lenses are based on Human-Centered Design and Design Thinking frameworks for innovation and innovative products. In order to evaluate the effectiveness of PFX at improving technical quality, manufacturability, and user satisfaction of end designs, we assess functional prototypes developed in a junior-level mechanical engineering design course. Results from a between-subjects analysis indicate that using PFX can help increase the desirability, feasibility, and viability of functional prototypes when those lenses are applied; specifically, student teams introduced to PFX produced prototypes that outperformed those from control teams with no formal prototyping methods on user satisfaction, perceived value, and manufacturability metrics. This study confirms the impact that structured prototyping methods like PFX can have on the prototyping process and final designs. In order to understand the effect of structured and holistic prototyping models on designers themselves, we evaluate the impact PFX has on designers’ prototyping awareness. The prototyping literature has typically evaluated the few prototyping methods, tools, and frameworks using design-based metrics, such as binary evaluations of completion of a design task. Based on a detailed literature review, we hypothesize that structured prototyping methods, specifically PFX, can increase novice designers’ and engineering students’ self-efficacy, leading to an increase in feelings of control throughout the prototyping process, which may lead to an increase in creative output, higher levels of motivation, and an increase in the quality of final designs. As an initial step in the measurement of these outcomes, we sought to understand if PFX influences designers’ prototyping awareness. In order to measure prototyping awareness, a new measurement tool is proposed and validated, the Prototyping AWareness Scale (PAWS). Results from this study partially support the notion that structured prototyping frameworks influence the prototyping awareness of novice engineering designers. Finally, the work concludes with a study exploring the effect that PFX might have on the prototyping process itself. We sought to understand how the order or sequence of PFX lenses might affect the feasibility, viability, and desirability of an end design and the prototyping awareness of engineering designers. The results of our findings indicate that the sequence of PFX lenses has some effect on product outcomes and prototyping awareness. The contributions from this research lie primarily in the field of engineering design, specifically in the area of prototyping during the new product design process. They include: 1) establishment of four specifications for a structured and holistic prototyping framework, 2) development of the Prototype for X framework, 3) creation of alternative metrics to evaluate prototypes, 4) creation of a scale to measure prototyping awareness and 5) validation of the effect of a structured prototyping framework on the many facets of a product. Future work will explore in more detail the full effect of lens sequencing on design and designer outcomes, but this initial work highlights the potential of PFX to be used in new product development to positively influence products and designers. Future work will focus on validating the PFX framework in industry settings and studying the effects of PFX on the designers’ understanding of prototyping, the decisions made during prototyping, and the artifact produced during prototyping.