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Carlye A. Lauff
Mem. ASME
Department of Mechanical Engineering,
University of Colorado Boulder,
Idea Forge, 2445 Kittredge Loop Road,
Fleming Building, FLEM 77,
Boulder, CO 80309
e-mail: Carlye.Lauff@colorado.edu
Daria Kotys-Schwartz
Mem. ASME
Department of Mechanical Engineering,
University of Colorado Boulder,
Idea Forge, 2445 Kittredge Loop Road,
Fleming Building, FLEM 130F,
Boulder, CO 80309
e-mail: Daria.Kotys@colorado.edu
Mark E. Rentschler
Mem. ASME
Department of Mechanical Engineering,
Engineering Center,
University of Colorado Boulder,
ECES 150 1111 Engineering Drive,
Boulder, CO 80309
e-mail: Mark.Rentschler@colorado.edu
What is a Prototype? What
are the Roles of Prototypes
in Companies?
Prototyping is an essential part of product development in companies, and yet it is one of
the least explored areas of design practice. There are limited ethnographic studies con-
ducted within companies, specifically around the topic of prototyping. This is an empiri-
cal and industrial-based study using inductive ethnographic observations to further our
understanding of the various roles prototypes play in organizations. This research
observed the entire product development cycle within three companies in the fields of
consumer electronics (CE), footwear (FW), and medical devices (MD). Our guiding
research questions are: What is a prototype? What are the roles of prototypes across
these three companies? Through our analysis, we uncovered that prototypes are tools for
enhanced communication, increased learning, and informed decision-making. Specifi-
cally, we further refine these categories to display the types of communication, learning,
and decision-making that occur. These insights are significant because they validate
many prior prototyping theories and claims, while also adding new perspectives through
further exploiting each role. Finally, we provide newly modified definitions of a prototype
and prototyping based on this empirical work, which we hope expands designers’ mental
models for the terms. [DOI: 10.1115/1.4039340]
Introduction
“Prototyping is one of the most critical activities in new product
development” [1], and yet “prototyping may be simultaneously
one of the most important and least formally explored areas of
design” [2,3]. Research on the product development process has
often focused on early stages of design, such as concept genera-
tion and selection [4–10]. Topics like sketching [11–14], design
fixation [15–18], and product dissection [19–21] have been stud-
ied extensively. More recently, studies have begun exploring the
phase of prototyping within mechanical engineering [2,22–27].
Most of these studies focus on developing strategies to prototype
[2,22,25,26] or on testing specific hypotheses, such as if fewer
parts in prototypes correlate with better final designs [23,24].
These contributions have largely studied student design teams in
universities, which has significantly contributed to our under-
standing of prototypes [2,12,16,22–27]. However, there are rela-
tively few studies regarding the role of prototypes within
company contexts [28,29]. We contribute to this area by exploring
the nature of prototypes across three diverse industries, which
allows us to compare our findings to the existing literature on pro-
totypes. Our research inductively derives three roles and a new
definition for prototypes using a grounded theory approach [30];
the insights emerge from empirical observations over 10 months
in companies in the fields of consumer electronics (CE), footwear
(FW), and medical devices (MD).
Relevant Literature
Prototyping in the Design Process. Research around prototyp-
ing has increased in the last two decades. There is an abundance
of prototyping studies from fields like computer science and
human–computer interaction (HCI), while limited in comparison
studies from mechanical engineering.
Within the field of mechanical engineering, researchers have
developed several prototyping strategies for novice designers
[2,3,22,25,26,31]. Students, as a type of novice designer, often
have a narrow perception of prototypes and thus need guidance
while prototyping [32,33]. In these frameworks, novice designers
are prompted with questions prior to prototyping ranging from
topics about the technical elements of the intended design to
resource allocation and management.
While there are numerous prototyping taxonomies, models, and
frameworks [34–39], there is “still a lack of knowledge about the
fundamental nature of prototypes due to their complex and
dynamic nature” [38]. Houde and Hill’s seminal work on proto-
typing from HCI describes prototypes as existing on an interactive
triangle with four main features: role, implementation, look and
feel, and integration [36]. Recommendations from their work
include defining prototypes broadly, building multiple prototypes
throughout the design process, and preparing prototypes based on
the audiences. As such, we have taken a broad approach to defin-
ing prototypes as any manifestation of the design, to ensure that
we capture all prototypes and prototyping practices in our
research. Our focus is to add value to the field by validating some
of these prior findings, while adding new insights around the roles
of prototypes from industry.
Empirical Studies of Design Practice. Empirical studies of
companies further our understanding of “design in the wild,”
which is critical to developing grounded theory out of practice
[40]. Early design researchers used empirical data from compa-
nies, like Kodak [1], Apple [41], and other high tech firms
[28,29,42,43], to understand design practices before developing
theories or strategies to implement in organizations.
Several prominent researchers have studied design practices
and subsequently shifted mindsets about the field and “science of
design” including Simon [44], Sch€
on [45], and Latour [46,47].
More recently, scholars from the field of engineering, such as
Contributed by the Design Theory and Methodology Committee of ASME for
publication in the JOURNAL OF MECHANICAL DESIGN. Manuscript received September
24, 2017; final manuscript received February 2, 2018; published online March 23,
2018. Assoc. Editor: Katja Holtta-Otto.
Journal of Mechanical Design JUNE 2018, Vol. 140 / 061102-1Copyright V
C2018 by ASME
Bucciarelli [48–50] and Trevelyan [51,52], specifically studied
engineering design in practice. Design work is often considered
fundamental to engineering, and thus, observing engineering in
practice gives insights to the entire design process [53]. Bucciarel-
li’s Designing Engineers presents a critical perspective on the pro-
fession of engineering design [50]. He argues for a view of
engineering as a social construction process reconciling goals,
objectives, tests, and interpretations in the development of a prod-
uct by participants with perspectives from different “object
worlds.” Similarly, Trevelyan studied professional engineers in
locations across Australia and Asia. He states that “the foundation
of engineering practice is distributed expertise enacted through
social interactions between people: engineering relies on harness-
ing the knowledge, expertise and skills carried by many people,
much of it implicit and unwritten knowledge. Therefore social
interactions lie at the core of engineering practice” [52]. This is
referred to as technical coordination, where the social is always
intertwined in the technical [51]. We believe that this concept of
technical coordination is essential to the creation of prototypes; it
helps explain how designers coordinate various technical knowl-
edge and embody it within a prototype.
There are two qualitative research studies that were conducted
within company contexts and focused specifically on understand-
ing prototyping [28,29]. Gerber and Carroll conducted an 18-
month ethnographic study of a high-tech firm using the theoretical
framework of design as a learning process. This study focused on
the psychological experience of engaging in low-fidelity prototyp-
ing, and their outcomes showed that low-fidelity prototyping
allowed employees to reframe failure as a learning opportunity,
support a sense of forward progress, and strengthen beliefs about
creative ability [28]. The second empirical study from Jensen et al.
described how prototypes are used to elicit “unknown unknowns”
on company projects [29]. Unknown unknowns are aspects of the
design not considered prior to building and testing the prototype.
They conducted a mixed-methods study, using a collection of
observations, interviews, and artifacts. They analyzed nineteen pro-
totypes across eight companies in terms of functionality, timing,
stakeholder involvement, and requirement elicitation. Both of these
research studies further our understanding of prototypes in compa-
nies. Our research builds on these empirical studies, by using ethno-
graphically informed methods and a grounded theory approach to
understand the various roles prototypes serve across three different
industries.
Theorizing Objects in the Design Process. Since prototypes
are at the core of this research, we surveyed relevant theories
describing objects during the design process. Two of the most
well-established theories include Vinck’s intermediary objects
[54–56] and Starr’s boundary objects [57,58]. Intermediary
objects mark a transition from one stage of the design process to
another, or else coordinate meaning between different groups of
people. They act as communication and coordination tools, while
also mediating and exploring the roles between people. Boundary
objects have a broader interpretation; they can be concrete or
abstract objects or ideas, which are also a form of communication
between people. Within engineering design, an example of a
boundary object is a computer-aided design drawing. This draw-
ing is used to communicate design intent between engineers and
machinists; the object is robust enough to maintain a common
identity between parties, and yet plastic enough to adapt to local
needs and constraints of the various people employing them.
Within engineering design, Henderson studied visual represen-
tations in the design process, ranging from sketches to computer
models to prototypes [59]. She argues that material objects are
critical in the design process, and she reported that design cultures
are intrinsically tied to how product representations are con-
structed in companies, and that these visual representations create
tacit knowledge [60]. People gain tacit knowledge when creating
prototypes, often about materials, manufacturing processes, and
other technical aspects. This knowledge is embodied in the time
taken to plan, build, test, and iterate on the prototypes, which can
be difficult to replicate through more traditional learning methods
like reading or lectures. Henderson used guiding principles from
actor-network theory, which acknowledges that both humans and
objects are equal “actors” when analyzing social situations. This
shift in thinking about objects as equal in importance to humans
opens new opportunities for seeing the value that objects, like pro-
totypes, add during design projects.
Research Design
This is a qualitative research study, which allows us to observe
design practices and ask open-ended questions about how proto-
types are used and why they are used in those instances [61].
There is not one straightforward research design for a qualitative
study. As Maxwell summarizes, “qualitative research design…is a
‘do-it-yourself’ rather than an ‘off-the-shelf’ process, one that
involves ‘tacking’ back and forth between different components
of the [research] design, assessing their implications for one
another” [62]. In this research, we borrow techniques from various
traditions, such as ethnography, case studies, and grounded
theory. We combine these approaches to answer our guiding
research questions: What is a prototype? What are the roles of
prototypes across these three companies? These guiding questions
are open-ended and broad so that we do not limit the scope of our
inductive analysis and emergent findings. These research ques-
tions emerged from our prior work in companies [63,64] where
we observed the importance of objects in the design process,
and from our pilot studies that uncovered the differences in defini-
tions and understandings of prototypes between students and
professionals [32].
Conceptual Framework. The conceptual framework for this
research is informed by the theory of heterogeneous engineering
from the field of Science and Technology Studies, which has roots
in actor-network theory. Heterogeneous engineering was a con-
cept first introduced by Law [65] and then used by Suchman [66]
to describe the process of building a bridge. Heterogeneous engi-
neering is the view that engineering design is a complex system of
mutually constitutive social and technical relations. When Such-
man examined a quintessential engineering project, building a
bridge, she found that social processes are not merely an aspect of
the design that is separable from technical processes; rather, the
design of the bridge represents the mutual constitution of material
and social relations through the joint production of a stable artifact
[66]. This informed our study in the way that we analyzed the
data, as we searched for instances that combined interactions
between people and objects, namely, the development of proto-
types. Additionally, we used the social science theories on objects
(i.e., Vinck’s intermediary objects [54–56], Starr’s boundary
objects [57,58], and Henderson’s visual representations and tacit
knowledge [59,60]) described in the relevant literature to aid in
our data analysis, especially during theoretical coding as
described in Fig. 1.
Companies. We studied three companies from the U.S., each
for the duration of one product’s design and development.
1
An
overview of the companies is in Table 1. These companies mass
produce physical products in the fields of consumer electronics,
footwear, and medical devices. The diversity in companies allows
us to compare the role of prototypes across them during data
analysis.
Company 1: Consumer Electronics Company. The first organi-
zation is a medium-sized, privately held CE company. There are
1
Names of companies, employees, and products are removed for confidentiality.
This research follows the guidelines from the Institutional Review Board under
protocols #13-0410 and #15-0659.
061102-2 / Vol. 140, JUNE 2018 Transactions of the ASME
approximately 200 employees at their headquarters, where all of
the design, manufacturing, and distribution occur. At CE, there is
a primary engineer assigned to each design project, and they are
required to conduct the majority of the design work for that pro-
ject. The engineers typically work on three to six projects at a
time, and they are each responsible for launching up to thirty new
or revised products a year. The engineer must complete three
internal design reviews that serve as major milestones in their
product development process: one for the specification and
requirements product report, one for the conceptual design and
schematics of the product, and one to review the first round of full
system prototypes. The lead engineer collaborates with represen-
tatives from production and quality assurance alongside the engi-
neering manager for these reviews. The project we observed was
the design of an electronic audio board. The product development
occurred over ten months, beginning in March 2016 and ending in
December 2016; the audio board was launched in early 2017.
Company 2: Footwear Company. The second organization is a
large, publicly held FW company with their headquarters in the
United States and offices worldwide. There are approximately
2000 employees involved in the design and development proc-
esses. FW starts the design process for a season of footwear
18 months before the products launch. Their process is broken
into four major phases: design, early development, late develop-
ment, and commercialization. Within each phase, there are several
major milestones. In this research, we observed the kids’ footwear
team and the creation of a new snow boot for the fall/winter
2017 line. The design process began in March 2016 and the boot
development was finished in December 2016. Between January
and April 2017, the team worked to finalize commercialization
details and mass production, and then the product line launched in
August 2017.
Company 3: Medical Device Company. The third organization
is a large, publicly held MD company specializing in surgical
products. The headquarters is in the U.S., and they have eight
additional manufacturing, distribution, and design facilities glob-
ally. There are approximately 3500 employees worldwide. Their
design process is influenced by the medical device regulations in
the United States. There are strict verification and validation
stages, where immense testing and documentation occur to ensure
the product passes all requirements. We observed the develop-
ment of a surgical device. The project began in June 2014, and it
was observed until March 2015 when the project paused due to
company restructuring. This project is still on hold, although
majority of the design and development work is complete.
Data Collection and Analysis. In this qualitative study, we
borrow techniques from ethnography, grounded theory, and case
study research to aid in data collection and analysis. Data analysis
began concurrently with data collection and continued for eight
months following. Figure 1displays the iterative process used dur-
ing this research study and highlights the various techniques for
data collection and analysis.
Data Collection—Ethnographically Informed Methods. We use
a variety of fieldwork methods to capture participants’ activities
throughout the product development cycle. Our approach to data
collection is ethnographically informed and includes both direct
and indirect methods for conducting fieldwork in modern societies
[67]. The guiding research questions and conceptual framework
influenced data collection, as shown in Fig. 1. As such, we paid
attention to social situations when people interacted or referenced
different objects, such as prototypes.
These methods for data collection include: (1) observations in
the workplace; (2) written field notes during observations that are
subsequently summarized and logged daily; (3) audio recordings
of informal interviews, inspired by the traditions of ethnographic
interviews [68], which occurred at the beginning of the research
to build rapport and understanding and then toward the end to val-
idate emergent findings; (4) audio or video recordings of individ-
ual and collaborative activities including team meetings and
design-stage gates; (5) collection of materials and artifacts that are
produced by participants during their work, which includes (6)
photographs of physical paper documents, (7) shared copies of
electronic documents (i.e., e-mails and online collaborative plat-
forms like DropBox), and (8) photographs of temporary surfaces
like whiteboards, spaces and rooms where design activities took
place, and (9) any physical artifacts like prototypes. These types
and amounts of data collected are displayed in Fig. 1.
Data collection occurred at the companies for the entire dura-
tion of each product’s development. The time spent at each com-
pany varied by week, depending on the access and the number of
meetings or events occurring. The primary researcher was given
security badge access and office space to work at each location,
further embedding them as participant observers at the companies.
During the first few months at each company, the primary
researcher spent between five and ten hours at each company per
week, spread out over two to three days. As the research pro-
gressed, they visited the companies once a week for two to four
hours. The hours of observations were reduced once the research
Fig. 1 Research methods process
Table 1 Summary of companies in research study
Company 1 Company 2 Company 3
Industry Consumer electronics Footwear Medical devices
Project followed Audio board Kid’s winter boots Surgical device
Dates of observations March–December 2016 March–December 2016 June 2014–March 2015
Duration of observations 10 months 10 months 10 months
Size of core design team 4 people 8 people 15 people
Status of product Launched Launched Project on hold
Journal of Mechanical Design JUNE 2018, Vol. 140 / 061102-3
team reached saturation in understanding the role of prototypes.
Saturation in qualitative data occurs once there are no additional
emerging themes from the concurrent data analysis.
Data Analysis—Grounded Theory Approach. Data analysis was
influenced by the techniques used in grounded theory develop-
ment [69]. It takes an inductive, comparative, and interactive
approach to inquiry and offers several open-ended strategies [30].
Three tenants of grounded theory are: (1) creating the conditions
for emergent inquiry through the systematic and active scrutiny of
data; (2) the successive development and checking of emergent
categories; and (3) the use of constant comparative analysis [70].
It intertwines data collection and analysis. The emergent themes
from early analysis inform future data collection.
In conducting our analysis, we used the five-level coding proce-
dure for constant comparative analysis as shown in Fig. 1[30,70].
These phases are conducted iteratively until theoretical saturation
is reached and no new themes emerge. These five-levels are: (1)
open coding, segmenting initial data into preliminary categories;
(2) axial coding, organizing preliminary categories into broader
themes; (3) selective coding, refining categories and themes
toward an overarching theory or framework; (4) theoretical cod-
ing, comparing themes to known theories and concepts; and (5)
theoretical categorization, developing a sound theory or frame-
work to describe the phenomena in the study.
The lead researcher transcribed and initially coded the theoreti-
cally sampled data. Theoretical sampling is selecting subsequent
data to collect and analyze along criteria that will allow us to test and
expand the scope of our grounded theory. As such, we often select
potential negative cases of data to validate or expand our coding
scheme. Then, two additional researchers analyzed the data independ-
ently using the evolving codebook. Each researcher would highlight
or select portions of text that supported any of the primary, secondary,
or tertiary codes. As a team, we used a combination of Microsoft
Word/Excel digital data documents, physical printed copies of data,
and the NVivo platform to code our data and evolve our codebook.
This codebook evolved into its final state, displayed in Table 2,after
achieving unanimous agreement amongst the three researchers. Unan-
imous agreement is reached when there are no discrepancies between
the data coded by the three independent reviewers.
An example of coding data is shown here: as one researcher
reads through a transcription of a design meeting after watching
the video clip, they highlighted the segment of text “we were
wondering if we should move these lights [on the prototype] …or
something?” and link this language and actions to the primary
code of “communication,” the secondary code of “gathering
feedback,” and the tertiary code of an “active medium.” In this
example, the product developer is speaking while holding and
interacting with the prototype. This person is talking to the rest of
the design team, trying to gather their feedback on what changes
should be made to the lights in the current design. It is critical to
triangulate multiple types of data during analysis—video data,
verbatim transcriptions, and the field notes—to gain a holistic pic-
ture. The field notes aided in selecting the data initially, then it was
transcribed by the primary researcher, followed by the research
team watching the video clip during a data analysis meeting, and
then finally each researcher coded the transcriptions, and these
were compared to one another to populate the evolving codebook.
We used constant comparative analysis to compare codes and
categories from previously collected data to those of recently col-
lected data, as supported by analytic memo writing [71]. We also
considered each company to be their own case and subsequently
used a comparative case study approach to aggregate the different
categories for the roles of prototypes between the three organiza-
tions. The research team gathered once a week for 60–90 min over
18 months to review the theoretically sampled data and iterate and
evolve the codebook, as displayed in Table 2.
Ensuring Validity. There are various strategies for ensuring
validity in qualitative projects [62,67,71], and suggestions from
Table 2 Data analysis codebook
Main codes Subcodes Tertiary codes across all subcodes Definitions from main and subcodes
Communication Explain Standalone representation (passive) Using prototypes to explain the idea, concept, or design. This can include better defining the intent or
trying to create a similar mental model between multiple people.
Feedback Active medium Using prototypes as a medium to facilitate feedback from others on how to improve the design.
Negotiate Using prototypes to negotiate aspects of the design.
Persuade Using prototypes to persuade others to choose the design or aspects of the design. This could be consid-
ered “priming” others to sell the idea, too.
Learning Product space Reinforcing knowledge Using prototypes to learn about the product design space. This includes understanding related designs,
companies, similar products (benchmarking), new technologies, reverse engineering, and more.Gaining new knowledge
Technical elements Using prototypes to learn more about technical aspects of the design related to feasibility, functionality,
and the processes required to create it. This can occur through building and testing, reverse engineering,
trouble-shooting, experimenting, and similar.
User interest Using prototypes to learn more about users’ interests both internally in the organization and externally
with consumers and other key stakeholders.
Business related Using prototypes to learn about business related elements. This can include topics like costing, bill of
materials, supply chain aspects, processes to create the artifacts, and similar.
Decision-making Desirability Incremental Using prototypes to make decisions about desirability of the design from multiple users’ perspectives.
MilestonesViability Using prototypes to make decisions about viability of the design related to the business aspects.
Feasibility Reference points Using prototypes to make decisions about technical elements of the design related to feasibility, func-
tionality, and processes to create it.
061102-4 / Vol. 140, JUNE 2018 Transactions of the ASME
these papers have informed the validity of this study. Maxwell
outlines eight methods to ensure validity [62], and we use seven
of these methods to strengthen our qualitative study: (1) intensive
long-term involvement with the companies (10 months at each
company); (2) rich data collection in multiple forms (i.e., video,
audio, transcriptions, digital documents); (3) respondent valida-
tion of the emergent themes; (4) searching for discrepant evidence
and negative cases; (5) analysis conducted on a diverse research
team; (6) triangulation of multiple sources of data (i.e., compari-
sons between observations, field notes, interviews, e-mails); and
(7) comparisons between the emergent roles of prototypes across
the three companies as different cases.
Emergent Findings
Emergent Roles of a Prototype. First, we describe the three
salient roles of a prototype that emerged inductively. Our findings
suggest that prototypes (1) enable communication, (2) aid in
learning, and (3) inform decision-making. A prototype can
encompass multiple roles at once. Each role can be further refined
by subcodes and tertiary codes, allowing for richer descriptions of
the roles. For example, “persuade” is a subcode under communica-
tion, which allows us to discuss how prototypes can act as a tool to
persuade others about the design as a specific type of communica-
tion. In the following paragraphs, we explore these three overarch-
ing roles of a prototype in each of the three companies, while
emphasizing the subcodes and tertiary codes for each of these roles.
In the Discussion section, we compare how the emergent themes
validate existing literature and also provide new perspectives.
Role 1: Prototypes Enable Communication. The first emergent
theme is that prototypes enable communication. We identify four
types of communication enabled by prototypes, which include:
(1) explaining a concept,
(2) enabling feedback,
(3) facilitating negotiations, and
(4) persuading others.
For each of these, prototypes are a communication tool either
as a passive standalone representation or an active medium for
discussion. Prototypes are passive when they are referenced or
discussed without direct interaction and active when they are
being physically or digitally interacted with by individuals.
Prototypes enable communication by creating a similar mental
model between people, thus reducing the cognitive burden that
can occur during an abstract, verbal conversation. Thus, they cre-
ate a common design language. As part of persuasion, prototypes
can be used to induce a priming effect on people. This can result
in making decisions on a project based on being primed by a pro-
totype at a meeting, which could alter the decision compared to if
those people were never shown that prototype. Often, multiple
types of communication are enabled in the same situation around
the same prototype. For example, a prototype can first create a
common language between two or more people. Then, once that
common ground is established, it can be used to gather feedback
or negotiate aspects of the design.
To exemplify this theme of communication, we first show an
excerpt from a weekly team meeting at the footwear company. In
this meeting, one product developer updates the rest of the team
on the changes to the prototype of the kids’ snow boot. In discus-
sing these changes, the product developer uses the prototype as an
active medium (Fig. 2, top) to further explain the detail of the
alterations. Every time the words “here,” “it” or “this” are used, it
refers to the prototype on the table.
Product Developer: So as the boot grew [in height], our angle has
changed here in the boot. So as you grow taller, it is going to kind-
of come up a bit. So I’m going to work to correct the sharpness of
the turn and then kind of clean all this up. And this will be vertical.
Project Manager: Is that the right height? Are we good? We
feel good about that height [on the boot]?
Product Developer: As far as our instructions go, yeah we are.
Um, so, everything will be sharpened and angled instead of just
these squiggly free lines. Though, seeing this, you do have this
gentle movement here in the heel-collar, um, is there anything you
guys are seeing? Should it be swoopy? Should it be hard-edge?
Project Manager: I think it’s too swoopy.
In this instance, the prototype assists the team in multiple forms
of communication. First, it is used by the product developer to
explain the changes with the boot, thus making everyone aware of
the current design. Then, it is used to facilitate discussion and
feedback from the team members. In this excerpt, the project man-
ager responds to the product developer and asks for clarification
on the height of the boot, while also trying to facilitate discussion
amongst the team so that they can make a decision regarding the
boot height. The product developer responds to the height concern
and poses two vague questions to the team: “Should it be swoopy?
Should it be hard-edged?” These statements can be made because
the prototype is used as a reference point in the conversation, with
little concern for misunderstandings. This mixture of verbal con-
versation and physical interaction with the prototype aids the team
in developing a shared understanding how the next iteration of the
boot will change. In this example, the prototype of the boot is a
tool that creates enhanced communication between the members
on the team, which reduces the chance of any miscommunication
and different interpretations.
The ability for prototypes to create clear communication is fur-
ther demonstrated when compared to an example when no proto-
type is used during a team meeting. In this segment, there are
three engineers from the medical device company discussing a
button feature on the surgical device being designed. The engi-
neers are confused by the terminology, as some call this button
feature a rocker switch. Some people use the terms interchange-
ably, while others feel that they are distinctly different.
Fig. 2 Prototypes of the kid’s winter boots from the footwear
company: early iterations of different materials, boot heights,
and closure systems
Journal of Mechanical Design JUNE 2018, Vol. 140 / 061102-5
Engineer 1: By button, do you mean the rocker switch?
Engineer 2: Yeah. Obviously, well—that doesn’t mean that—
the rocker button it’s called… The switch is different.
Engineer 3: Well I was kind of curious about the nomenclature
with that, too. Because there’s two buttons on the rocker switch,
and so you see what I’m saying?
Project Manager: Don’t call it a switch. It’s not a switch, it’s a
button.
This challenge in nomenclature about a feature on the prototype
causes delays to the team meeting. In this example, the “button”
versus “rocker switch” discussion occurred for ten minutes and
derailed the primary purpose of the team meeting. One remedy to
this challenge is showing the part of the prototype that is being
discussed, either digitally or physically, as a way to create a com-
mon language (or similar mental model) between parties. This
combination of verbal conversation and visual representation,
through a prototype, could reduce the chance of confusion when
explaining something technical to the team. This miscommunica-
tion on the surgical device is similar to what could have occurred
with the boot when they used terms like “swoopy” and “hard-
edge.” The terms can be interpreted differently, causing mental
burden and confusion, without the aid of visual representations
like prototypes during the discussion.
We provide one final example from the consumer electronics
company that shows how prototypes are used to persuade others.
In this example, a cross-disciplinary team from engineering, manu-
facturing, quality-assurance, and marketing meet to discuss where
the company should invest in new products. They have an open
platform where any employee can submit product ideas. In this
meeting, the team discusses four new ideas submitted by employ-
ees. Out of these ideas, two receive a “yes” to move forward toward
product development, while the other two ideas receive a “no.”
The two ideas that received a yes were both further developed
concepts; one idea had a simple prototype built to prove the con-
cept. The marketing manager stated in regard to one of these
“yes” projects that, “I really like effort here – the direction this
seems to be going.” The engineering manager further comments
on the concept with the prototype, stating that “he has already
proven the concept here, even roughly. I think it is worth pursuing
further now.” The other two ideas that were given a “no” were
less specified in their submission, and that ambiguity in the design
seemed to drive the decision to reject the proposals. The engineer-
ing manager stated, “I just wish that this person would have taken
the time to fill out the spec. It just shows no effort at all.” The
manufacturing manager added, “I don’t even know what it is that
they want to make or what problem they are trying to solve.”
There were likely several factors that contributed to these deci-
sions, one factor being that the simple prototypes were a priming
tool to influence decision-making. These prototypes, one as a writ-
ten detailed description/specification list and the other as a photo-
graphed representation of the physical object, were able to
communicate clearly the intended products. In this instance, the
simple prototypes served as a standalone representation for the
managers to interpret. It is important to be cognizant about this
psychological priming effect of prototypes throughout the design
process, as it can influence decision-making based on perceived
effort, rather than the merit of the concept.
In summary, prototypes provide value to companies, especially
in enabling clear and concise communication between multiple
stakeholders. These examples support our claims that prototypes
are communication tools for explaining a concept, gathering feed-
back, aiding in negotiations, and persuading others.
Role 2: Prototypes Aid in Learning. The second emergent theme
is that prototypes aid in learning. We have uncovered several catego-
ries where learning occurs through developing, interacting, or refer-
encing prototypes. These include using prototype to learn about:
(1) the design space, including comparable products and
related technologies;
(2) technical elements required in the design;
(3) users’ preferences, interests, and behaviors; and
(4) business-related topics, such as costing for materials and
manufacturing.
For each category, those involved can learn new information or
reinforce already learnt knowledge through the prototypes. Our
approach to identifying these types of knowledge gathering tech-
niques is similar to how others have described the design process
as working toward understanding and discovering values for all of
the known unknowns,unknown knowns, and unknown unknowns
2
about the product [29,72].
One way that companies often learn about the product space
early in the design process is by benchmarking related designs.
Benchmarking can be as simple as browsing competitors’ prod-
ucts and reading online reviews, or it can be a more complicated
process using techniques like reverse engineering. We consider
reverse engineering a product to be a form of prototyping, espe-
cially if the intent is to borrow techniques for materials and con-
struction or to solidify the design of their new product.
We first show an example of benchmarking and reverse engi-
neering a competitor product, as a form of prototyping for learn-
ing, from the footwear company. This example comes from a
weekly team meeting, where team members discuss the design of
the kids’ snow boot. The present team members are the product
developer, project manager, and product designer. The product
developer is responsible for bringing this product to mass produc-
tion; part of their job is material sourcing and establishing the pro-
cedure for boot construction. The project manager oversees the
entire team and focuses on meeting milestones and staying within
their allocated budget. The product designer works on front-end
product ideation and is responsible for creating the two-
dimensional product representations that are then given to the
product developer to build. In this excerpt, these three people are
discussing the changes to the boot prototype through comparing it
to a competitor product. The team purchased a competitors’ boot,
which they deconstruct to evaluate the materials and construction.
They compare the competitor boot next to their current boot pro-
totype to evaluate the aesthetics and functional closures.
Product Developer: Right now we have solved [the] waterproof
[problem] up to this point. And the only thing left is…
Project Manager: Now I just don’t feel like it’s a $70 boot…
Product Designer: How much is that [competitor] one?
Project Manager: $70
Product Designer: Well, we’d have to put some trims on it and stuff.
Product Manager: I’m also wondering if we should copy them
[the competitors] and have double tabs?
Product Designer: Yeah, yeah. That’s a good idea.
Product Developer: Put tabs on either side [of the boot] instead
of just the back?
Product Manager: Yes.
In this segment, the project manager uses the competitors’ boot
to spur possible changes to their design. Both the current proto-
type boot and the competitors’ boot sit side-by-side on the table
and are being physically interacted with at this meeting. Prior to
this meeting, the product developer deconstructed one competitor
boot to evaluate the waterproof materials (reverse engineering),
which aided in solving “the waterproof problem.”At the end of
the discussion, the team ultimately agrees with the project man-
ager and they change the boot to include two side tabs on the next
iteration of the prototype.
As shown in this example, the competitor boot allows the team
to learn more about the product space, including design features
and costing, through interacting with the competitor product.
They are reinforcing their knowledge about costing when they
2
Known unknowns are questions the designer knows need to be answered through
testing prototypes. Unknown knowns deal with the unknown knowledge of the
involved stakeholders. Unknown unknowns include details whose existence and
relevance is unknown to the engineering designer.
061102-6 / Vol. 140, JUNE 2018 Transactions of the ASME
indicate that the competitor boot with its number of features is
“worth $70.”This knowledge then challenges how many features,
like the side tabs, must be included on their product so that it can
be worth the same value as their competitor (business aspects).
In addition to learning more about the product space, prototypes
also help the team understand technical aspects of the design.
Building and testing prototypes aid the designers in building tacit
knowledge around the product [73], including uncovering known
unknowns and unexpected technical areas (which can be consid-
ered the unknown unknowns). If the prototypes do not work as
intended, then they can be deconstructed, or “debugged,” to aid in
learning about technical aspects. This process can solidify techni-
cal knowledge for the designers.
In the next example from CE, we show how prototypes can
enhance learning. Their new product development process
requires building and testing several full-system prototypes to
ensure that all questions about the product’s feasibility, desirabil-
ity, and viability are answered. In this interview segment, the lead
engineer ordered several integrated circuits (IC), referred to as
“chips,” to prototype and test for use in the audio board product.
The strategy was to prototype several options on breadboards to
learn about what was desired in the final design. Through building
multiple prototypes of the potential system, the engineer learned
about related products and technologies, while enhancing her own
technical understanding of audio boards. In this interview, the engi-
neer reflects on how interacting with these prototypes gave her new
perspectives on the form, usability, and desirability of the product.
She printed the IC schematics and data sheets to aid in these bread-
board prototypes and made notes on the physical sheets of paper as
part of her own learning process (Fig. 3, top). These notes are valua-
ble for creating future schematics for the project and are also a reflec-
tion of her technical learnings.
Lead Engineer: So the features I wanted came from using this
[chip]…
Researcher: You learned what you wanted in the final design?
And also what didn’t work with it?
Lead Engineer: Yeah, so I was like I don’t want to deal with
any crazy software. I don’t want to do too much file conversion
to get it on there, like if I can’t just plug it in, load it, and then
use it then I don’t want it. And I think that’s the way that a lot
of customers are, too. [The customers] who are starting out.
Researcher: So you are trying to be in the shoes of the customer
when designing the product?
Lead Engineer: Right, exactly.
In this example, the lead engineer is learning more about the prod-
uct space and technical elements that are required in the design.
These learnings are embodied in the multiple chips tested and notes
written on the printed schematic (Fig. 3, top). Her learnings then help
to inform decision-making, which is the third role of a prototype.
We provide one final example of how prototypes aid in learning
from the medical device company. At the project kick-off meet-
ing, the team spent the first day understanding the current version
of the surgical device on the market, and then the remainder of
that week scoping the design project for the improved device. It
was decided that the primary purpose of the new product, as stated
in the design brief, was to “improve the ergonomics, especially
the ability for surgeons to use the cutting and sealing features in
an easy and intuitive manner.” There was harsh feedback from
surgeons on the current version, indicating that the design of the
surgical device did not accurately take into consideration the pro-
cess the surgeon goes through when using the device in the oper-
ating room. This feedback was part of the motivation for this
project, along with optimizing the temperature distribution.
The team facilitator took the current device apart and labeled
all of the components (Fig. 4, top). Prior products, like this first
version of the surgical device, are considered prototypes since
they are used as a baseline product that provides critical feedback
when designing the improved the next version; these prior prod-
ucts help solidify the intent of the project. All of the prior prod-
ucts/prototypes were passed around the meeting room so that each
team member could physically interact with the devices. The team
also watched a live demonstration of the surgical device using
meat as the pseudo-tissue. Afterward, the woman leading the
demo allowed others on the team to try the device on their own;
five employees chose to use the device. One employee, who was a
new engineer to the company, said right afterward, “I feel like I
really understand how this feels now. It’s great, but I also get the
awkward handle-button placement while cutting and sealing.” It
is clear from the statement that by interacting with the prototype
this engineer was able to gain a new level of learning about the
surgical device. The engineer experienced first-hand the
Fig. 3 Prototypes from the audio board project at the CE com-
pany: sample IC for breadboard prototypes (top left), notes for
improvement on IC schematic from prototyping (top right), and
full-system prototypes (bottom)
Fig. 4 Prototypes of the benchmarked surgical device compo-
nents (top) and two different material handle halves created in
parallel (bottom) from the medical device company
Journal of Mechanical Design JUNE 2018, Vol. 140 / 061102-7
ergonomics of the device, and this learning about the functional-
ities will help him when improving the ergonomics of it.
A statement we heard multiple times in various forms across all
the companies is that “prototypes help you learn what you know
and learn what you don’t know.” It is easy to imagine that a design
will work perfectly in your mind, and by creating prototypes you
can validate if these ideas work in reality. Prototypes can help
employees learn more about the product space, technical elements,
user preference, and business aspects. These learning from the pro-
totypes can then inform decision-making, which is the third theme.
Role 3: Prototypes Inform Decision-Making. The third and final
emergent theme is that prototypes help inform decision-making
during the design process. We explore how interacting with or
referencing a prototype leads to decisions that are better informed.
We have seen prototypes help make decisions in three broad cate-
gories, including the:
(1) desirability of the product,
(2) viability of the product, and
(3) feasibility of the product.
Decision-making is at the core of the design process; it is what
allows you to move between stage-gates and meet deadlines [74].
Decisions around desirability deal with personal preferences from
the design team, end users, and all stakeholders. Decisions around
viability include all business-related aspects, such as things like
material costs, supply chain, and production rates. Lastly, deci-
sions around feasibility deal with all technical aspects of the
design from core components to system integration. Often, a sin-
gle prototype can answer questions related to all three of these
topics. This can speed up time in the design process and move the
product toward completion.
Prototypes help inform both small and large decisions. On
design teams, prototypes can aid in incremental decisions on a
daily basis. These small decisions culminate into a more refined
prototype that is presented at major milestone meetings. As such,
prototypes act as critical milestones for design projects, and, at
these points in time, larger decisions can be made to continue for-
ward with the product, pivot directions, or cancel the project alto-
gether. These milestones, such as internal or external design
reviews, add accountability to the project and keep the team on a
schedule. By requiring prototypes and testing to occur, the team
can ensure that members are held accountable. We saw earlier
iterations of prototypes referenced later in the design process; in
these instances, the prototypes act as a reference points to anchor
the decision-making about the product.
To exemplify this theme of decision-making, we share exam-
ples from the three companies. At the footwear company, proto-
types often help answer critical questions tied to all three
subcodes at once: desirability, viability, and feasibility. In the fol-
lowing excerpt, the design team meets to discuss changes to the
kids’ boot prototype after the first large milestone review with
external stakeholders. After the external review, the design team
synthesized the stakeholders’ feedback, using the current proto-
type to spur additional insights. Two of the major concerns were
the materials used and the functional closures.
Project Manager: So we just want to talk to you [the Material
Specialist] about this guy [boot prototype]. We sampled it in
two materials: one was a coated polyurethane (PU) and one
was a nylon. I don’t know if you can see the difference – this is
the nylon and this is the PU. We like the nylon; it seems to be a
little richer [in quality] than the PU. I don’t think we got cost-
ing on it so we aren’t sure if you know what the material is and
[how much it costs]?
Material Specialist: Wasn’t that [PU] the keystone material,
[Product Developer]?
Product Developer: So in the upper [material of the boot] in the
bill of materials we’ve got the upper material as the PU. And then
[the other prototype] is the keystone [nylon material], so yes.
Project Manager: You fit this [prototype] right? Kids didn’t
have a hard time getting this [boot] on and off?
Product Developer: Yeah it’s a good C10 [size]. For a snow
boot, it’s more of a rain boot fit. It is a little tighter in terms of
the shaft and the diameter. We know this type of a boot func-
tions fine for us.
Project Manager: Do we have time to sample two options? On
how it closes? Just sample two different closures.
Product Developer: Absolutely. It may not be in all color or…
but if the components are very similar [and we are] just using
them in a different way, [then] yes.
In this example, the prototypes are used to aid in decision-
making about materials, end user fit, and functional closures,
which relate to all three topics: viability, feasibility, and desirabil-
ity. The prototypes presented at the design reviews acted as mile-
stones in decision-making, while the iterations on materials for
prototypes are considered as tools for incremental decisions. In the
excerpt, the team compares the current prototypes for the material
costing (viability), and they determine that two more prototypes
need to be created to test the closures (feasibility). The team con-
firms that the current prototypes have been tested with potential end
users to see if the kids like them (desirability) and if the kids can
easily put the boots on their feet and close them (feasibility).
We show another example of how prototypes aid in decision-
making from the consumer electronics company. Their new prod-
uct development process includes ordering a production ready
prototype to test the technical elements of the board before they
commit to mass production. In this example, the lead engineer on
the audio board project describes how this project required two
rounds of full-system prototypes, which is more than normally
expected under ideal conditions. The second round was needed
because the device would not work properly; the lead engineer
debugged the system over several days with many incremental
decisions based on the prototypes. These prototypes are shown in
the bottom of Fig. 3: the one with the red-wire is the initial full-
system prototype, and the other two are the newly updated prepro-
duction prototypes. These prototypes informed decisions around
technical functionality for the final design and served as both
milestones and incremental decision-making platforms.
Lead Engineer: So I ended up going through two rounds of
prototypes.
Researcher: Did that help you decide on what features to include?
Lead Engineer: Yeah, and some things just didn’t work [on the
first prototype] … What I ended up doing was I made this huge
map and printed out where each connection was being made
and I actually applied a voltage directly to each one to see
what was happening.
In this example, the first full-system prototype was used to
check the technical elements of the design. This prototype was needed
to validate the functionality, which included checking if it worked as
intended compared to the paper schematic prototypes. The full-
system prototype also confirms whether the product can be made cost
effectively in terms of materials, components, manufacturing proc-
esses, and time so that the business can remain profitable (viability).
We describe one final example of how prototypes aid in
decision-making from the medical device company. The team is
on a tight one-year schedule for creating this new surgical device.
To meet deadlines, they create prototypes in parallel to inform
their decision-making. At this weekly team meeting, the different
material options for the surgical device handle are discussed. By
prototyping two material options in parallel (Fig. 4, bottom), the
team can make decisions about the aesthetics and location of the
buttons (desirability), functional elements like the space needed to
house the printed circuit board within the handle (feasibility), and
the cost of a mold for mass production (viability) quicker than if
they prototyped them in sequence. In this example, the project
manager and one mechanical engineer discuss the status of the
prototypes and the materials tested.
061102-8 / Vol. 140, JUNE 2018 Transactions of the ASME
Project Manager: Then my second question is, you mentioned
bosses [in the material]. Has the material strength of glass-
filled versus virgin material been completed?
Mechanical Engineer: It hasn’t. In this prototyping process, we
went ahead and ordered two different materials. We ordered
two just to see if they’re—if we can get away with using an
acrylonitrile butadiene styrene [plastic]. We’re trying to flush
that out in the design process, but we haven’t by any means
selected a material [yet].
Project Manager: Okay. Yeah, please include [another engi-
neer] on that. He’s a good resource for suggestions [on the
material] and whatnot.
In this example, the prototypes of the handle halves allow the
team to discuss aspects related to feasibility, desirability, and via-
bility all at once. Prototyping multiple handle materials in parallel
helped the team to make a decision on final materials for the
device, which relates to viability from a costing and material
standpoint and then feasibility from a technical perspective. These
prototypes serve as milestones for decision-making in the process
for materials.
Decision-making is at the core of the design process, and it is
the critical underlying role of prototypes. Prototypes often tran-
scend all three roles at once; they aid in communication between
people, facilitate deeper learning, and ultimately aid in more
informed decision-making.
New Modified Definition and View on Prototypes. Finally,
we present a new viewpoint on prototypes in the design process,
which includes our own modified definitions for a prototype and
prototyping. Bucciarelli argued that “design is just as much about
agreeing on set definitions and negotiating as it is about producing
the final technical artifacts or product” [50]. In our research, we
recognize that the term prototype is complex and thus sought to
understand the meaning of prototypes from practice [63]. We pro-
pose a new definition based on these three roles of a prototype,
which we hope will be further discussed, negotiated, and redefined
by the design research community.
Prototypes are complex and dynamic artifacts that shape many
social situations during product development. We conceptualize
prototypes as both active tools used in the design process and as
influential actors impacting social situations. As tools, prototypes
are devices used to actively carry out intentional functions. Proto-
types are tools used to for specific tasks throughout the entire
design process, such as gathering performance data during testing
to make informed decisions. As actors, prototypes shape social sit-
uations and networks, either intentionally or unintentionally. Pro-
totypes are actors that can either actively or passively shape social
situations during the design process. As a passive and uninten-
tional actor, prototypes might be left on display in the office and
cause impromptu conversations and discussions about the product
that ultimately influence the direction the team takes. As both
tools and actors, designers and other stakeholders can see the
value prototypes add as a platform for communication, facilitator
in learning, and aid in decision-making in social situations. It is
important to recognize that prototypes influence situations both
intentionally and unintentionally, through both active and passive
usage. These insights may appear as subtle distinctions in lan-
guage and terminology, but we believe that this fundamental shift
in mindset of prototypes as tools and actors throughout the
entire design process can influence designers’ approaches to
prototyping.
An engineering prototype is often described as a means to
“verify or improve functionality, performance and operation of a
novel device or system” [2] or “an approximation of a product
along one of more dimensions of interest” [75]. These definitions
emphasize prototypes’ purpose as aiding in technical elements of
the design. Early in our research, we chose to broaden the scope
of the term prototype based on prior literature, mainly from the
field of HCI [36,38]. The definitions provided here are broader
than these traditional engineering definitions and grounded in our
emergent findings.
A prototype is a physical or digital embodiment of critical elements of
the intended design, and an iterative tool to enhance communication,
enable learning, and inform decision-making at any point in the
design process.
Prototyping is the process of creating the physical or digital
embodiment of critical elements of the intended design.
In this modified definition, we use design as a broad term to
include anything from an initial idea to final product, service, or
process. We use the phrase physical or digital embodiment to
acknowledge the various mediums and levels of fidelity that a pro-
totype can embody. Prototype mediums can range from two-
dimensional, including hand sketches, story boards, paper digital
interfaces, and lines of code, to three-dimensional, including foam
models, computer-aided design renderings, three-dimensional
printed parts, and breadboards, to even four-dimensional, includ-
ing role playing, virtual reality, interactive processes, and service
design. These mediums are physical, digital, and immersive in the
fourth dimension. Prototypes can also range in levels of fidelity
from low-fidelity models created with simple materials like card-
board to high-fidelity models that include some of the same mate-
rials and components as will likely be in the final product.
We acknowledge that this definition of a prototype is very
broad. Just as others have noted [29], a broad definition can lead
to misunderstandings of what the term prototype encompasses.
Although it is argued that this can hinder exploitation of its full
potential, we believe that we must first acknowledge this breadth
of the term prototype and then subsequently be more purposeful
in describing prototypes and their various functions in the future.
Discussion
“Current terminology for describing prototypes centers on
attributes of prototypes” [38], and as such, we focus less on the
attributes of prototypes and more on the actions that the prototypes
enable. Our conceptual framework of heterogeneous engineering
views prototypes as equal and important actors in the design pro-
cess. Prototypes’ manifestation influences social interactions, and
therefore, enables new types of communication, learning, and
decision-making. Our findings add to the body of literature from
many social scientists on the importance of artifacts in the design
process. Communication, learning, and decision-making as broad
categories are not novel topics for prototypes; rather, we add new
perspectives in the emergent subcodes and tertiary codes for each
of these roles as seen in Table 2and described in the following
three paragraphs.
Prototypes, as objects in the design process, are well established
as a mode for communication [48,49,54–58]. They are a signifi-
cant form of design language [23]. They mediate many social and
technical situations [46,47,66], acting as a sort of “social-glue”
[59]. Envisioning the design process as an “object world” [49], it
expands our interpretation of how prototypes shape social situa-
tions. We build on these theories and claims by exploiting how
prototypes can be active or passive standalone mediums for com-
munication (tertiary codes under communication in Table 2). As a
tool for communication, prototypes enable a shared understanding
amongst people, which often reduces misunderstandings between
stakeholders. Further, we divide the types of communication into
four categories: explaining a concept, enabling feedback, facilitat-
ing negotiations, and persuading others (subcodes under communi-
cation in Table 2). The latter two subroles highlight the “power”
that prototypes embody. They serve as an actor on the design teams
influencing the future course of action and decisions made.
Professional designers are often considered reflective in prac-
tice [45]. By interacting with prototypes, these designers can rein-
force knowledge and/or gain new knowledge about the design
space, such as about the unknown unknowns [29]. Further,
Journal of Mechanical Design JUNE 2018, Vol. 140 / 061102-9
interactions with prototypes can enhance designers’ tacit knowl-
edge of a design space [59]. We divide learning through proto-
types, whether new knowledge or reinforcing knowledge (tertiary
codes under learning in Table 2), into four topic areas: design
space, technical elements, user-interest, and business-related
topics (subcodes under learning in Table 2). We exploit the broad
nature of prototypes, indicating that benchmarking and reverse
engineering products can be considered a form of prototyping,
too. Viewing prototypes as vessels of knowledge can emphasize
their importance to design teams and companies hoping to retain
knowledge of best practices and lessons learned.
Prototypes have been described as milestones in the design pro-
cess [75], or objects that mark transitions between stages [54].
Prototypes help to answer questions related to desirability, viabil-
ity, and feasibility [3,41]. We discuss prototypes further through
breaking them into three categories: tools for incremental deci-
sions, milestone decisions, and reference points to inform current
decisions (tertiary codes under decision-making in Table 2); and
by also describing how prototypes enable decisions to be made in
parallel or sequentially about topics related to desirability, viabil-
ity, and feasibility (subcodes under decision-making in Table 2).
Prototypes evolve over time, and as such, each incremental deci-
sion culminates into more refined milestone prototypes, eventually
leading to the launch of the product. There is value for companies
in recognizing how the decisions made with each incremental pro-
totype influences later decisions during milestones, and how pro-
totypes as reference points from the past also can influence
present-day decisions.
Further, we recognize that prototypes are “complex and
dynamic in nature” [38]. Our data suggest that prototypes first cre-
ate clear communication between all stakeholders and support
learning, as means to then enhance and inform decision-making.
For example, referencing the data from the footwear company, we
see how the prototypes for the new children’s winter boot are used
for communication and learning before making informed deci-
sions. Referring to the data in role 1, communication, we see the
initial physical full-boot prototypes as a platform to explain the
concept, gain feedback, and negotiate requirements first. Then,
these conversations lead to new learnings for the product devel-
oper about the angle for the boot entry point and overall height.
Here, the prototype boot is a tool for communication and learning
first, which then aids in making a unanimous decision to change
the boot height and angle. Referring to the data in role 2, learning,
we see that the competitor boot spurs ideas about how to make
their product more desirable, while still achieving a low-cost and
functional solution. These learnings emerge from interacting and
reverse-engineering the competitor boot, and then these insights
are discussed. The prototype is used as a tool to ensure that com-
munication is clear amongst the team members. Finally, the team
reaches decisions about changing the closure, side tabs, water-
proof material, and price-point based on the learnings and com-
munication that happened first.
Our data suggest that there is a typical process to how the roles
of a prototype manifest: prototypes must first be tools for commu-
nication and learning, sometimes sequentially or in parallel, before
they can better inform decision-making. The key is that these deci-
sions are being informed by the prototype itself, with support
from the clear communication and enhanced learnings that come
prior. We created a simple model to exemplify this process and
the interactions in Fig. 5. This is not meant to be a prescriptive
model, but rather a descriptive way to visualize how the roles of
prototypes manifest in practice across these three companies.
Conclusion
In conclusion, this research answered our two guiding ques-
tions: What is a prototype? What are the roles of prototypes across
these three companies? The findings come from our empirical and
industrial-based study using ethnographic observations and induc-
tive analysis across three companies in the fields of consumer
electronics, footwear, and medical devices. We provide a modi-
fied definition of a prototype, based on empirical evidence that
includes the three emergent roles. “A prototype is a physical or
digital embodiment of critical elements of the intended design,
and an iterative tool to enhance communication, enable learning,
and inform decision-making at any point in the design process.”
In this definition, we recognize the importance of conceptualizing
prototypes as both intentional tools and often unintentional actors
in the design process.
Decision-making is at the heart of the design process [74], and
likewise, decision-making is at the heart of prototyping. We posit
that there is a typical process that the roles of a prototype mani-
fest, and our data suggest that prototypes are tools for communica-
tion and learning first to then better inform decision-making
(Fig. 5). Prototypes are physical or digital manifestations of the
design, which allow people to interact with the artifact and use it
as a tool during conversations, to gather feedback, negotiate, or
persuade others, while also learning more about the requirements
for the final design. Ultimately, the end pursuit for a prototype is
informing, and enhancing, decision-making in the design process
to launch a product to market.
Finally, we acknowledge that as a design research community
we need to negotiate and further debate the definition of a proto-
type since it is a broad and ambiguous term. Instead of focusing
just on the attributes of prototypes, let us also focus on the actions
and outcomes from using prototypes. We provide our new, modi-
fied definition of a prototype as a platform to increase conversa-
tions about prototypes between different industries and academic
spaces, and to challenge preconceived notions and traditional
engineering mindsets about what are considered prototypes.
Acknowledgment
We sincerely thank the three companies in this research project.
We would also like to thank Dr. Daniel Knight from the Univer-
sity of Colorado who has significantly contributed to the research
design and data analysis, and the many formal and informal
reviewers who aided in the revisions of this paper.
Funding Data
National Science Foundation under the Graduate Research
Fellowship Program and CMMI (Grant No. 1355599).
References
[1] Wall, M. B., Ulrich, K. T., and Flowers, W. C., 1992, “Evaluating Prototyping
Technologies for Product Design,” Res. Eng. Des.,3(3), pp. 163–177.
[2] Camburn, B. A., Dunlap, B. U., Kuhr, R., Viswanathan, V. K., Linsey, J. S.,
Jensen, D. D., Crawford, R. H., Otto, K., and Wood, K. L., 2013, “Methods for
Prototyping Strategies in Conceptual Phases of Design: Framework and Experi-
mental Assessment,” ASME Paper No. DETC2013-13072.
Fig. 5 Three emergent roles of prototypes: communication
and learning to support decision-making
061102-10 / Vol. 140, JUNE 2018 Transactions of the ASME
[3] Menold, J., Jablokow, K., and Simpson, T., 2017, “Prototype for X (PFX): A
Holistic Framework for Structuring Prototyping Methods to Support Engineer-
ing Design,” Des. Stud.,50(1), pp. 70–112.
[4] Daly, S. R., Yilmaz, S., Christian, J. L., Seifert, C. M., and Gonzalez, R., 2012,
“Design Heuristics in Engineering Concept Generation,” J. Eng. Educ.,101(4),
pp. 601–629.
[5] Okud an, G. E., and Tauhid, S., 2008, “Concept Selection Methods—A L itera-
ture Review From 1980 to 2008,” Int. J. Des. Eng.,1(3), pp. 243–277.
[6] Yilm az, S., and Daly, S. R., 2016, “Feedback in Concept Development: Com-
paring Design Disciplines,” Des. Stud.,45(1A), pp. 137–158.
[7] Yilmaz, S., Daly, S. R., Christian, J. L., Seifert, C. M., and Gonzalez, R., 2014,
“Can Experienced Designers Learn From New Tools? A Case Study of Idea
Generation in a Professional Engineering Team,” Int. J. Des., Creativity, Inno-
vation,2(2), pp. 82–96.
[8] Toh, C. A., and Miller, S. R., 2016, “Choosing Creativity: The Role of Individ-
ual Risk and Ambiguity Aversion on Creative Concept Selection in Engineering
Design,” Res. Eng. Des.,27(3), pp. 195–219.
[9] Jin, Y., and Li, W., 2006, “Design Concept Generation: A Hierarchical Coevo-
lutionary Approach,” ASME J. Mech. Des.,129(10), pp. 1012–1022.
[10] Gosnell, C. A., and Miller, S. R., 2015, “But is It Creative? Delineating the
Impact of Expertise and Concept Ratings on Creative Concept Selection,”
ASME J. Mech. Des.,138(2), p. 021101.
[11] H€
aggman, A., Tsai, G., Elsen, C., Honda, T., and Yang, M. C., 2015,
“Connections Between the Design Tool, Design Attributes, and User Preferen-
ces in Early Stage Design,” ASME J. Mech. Des.,137(7), p. 071408.
[12] Bao, Q., Faas, D., and Yang, M. C., 2018, “Interplay of Sketching & Prototyp-
ing in Early Stage Product Design,” Int. J. Des. Creativity Innovation, in press.
[13] Orbay, G., and Kara, L. B., 2012, “Shape Design From Exemplar Sketches
Using Graph-Based Sketch Analysis,” ASME J. Mech. Des.,134(11),
p. 111002.
[14] Yang, M. C., and Cham, J. G., 2007, “An Analysis of Sketching Skill and Its
Role in Early Stage Engineering Design,” ASME J. Mech. Des.,129(5), pp.
476–482.
[15] Viswanathan, V. K., and Linsey, J. S., 2009, “Enhancing Student Innovation:
Physical Models in the Idea Generation Process,” 39th Frontiers in Education
Conference (FIE), San Antonio, TX, Oct. 18–21, pp. 1–6.
[16] Viswanathan, V. K., and Linsey, J. S., 2012, “Physical Models and Design
Thinking: A Study of Functionality, Novelty and Variety of Ideas,” ASME J.
Mech. Des.,134(9), p. 091004.
[17] Viswanathan, V. K., Atilola, O., Esposito, N., and Linsey, J. S., 2014, “A Study
on the Role of Physical Models in the Mitigation of Design Fixation,” J. Eng.
Des.,25(1–3), pp. 25–43.
[18] Viswanathan, V. K., and Linsey, J. S., 2013, “Design Fixation and Its Mitiga-
tion: A Study on the Role of Expertise,” ASME J. Mech. Des.,135(5),
p. 051008.
[19] Toh, C. A., Miller, S. R., and Kremer, G. E. O., 2014, “The Impact of Team-
Based Product Dissection on Design Novelty,” ASME J. Mech. Des.,136(4),
p. 041004.
[20] Booth, J. W., Reid, T. N., Eckert, C., and Ramani, K., 2015, “Comparing Func-
tional Analysis Methods for Product Dissection Tasks,” ASME J. Mech. Des.,
137(8), p. 081101.
[21] Thevenot, H. J., and Simpson, T. W., 2009, “A Product Dissection-Based Meth-
odology to Benchmark Product Family Design Alternatives,” ASME J. Mech.
Des.,131(4), p. 041002.
[22] Dunlap, B. U., Hamon, C. L., Camburn, B. A., Crawford, R. H., Green, M. G.,
and Wood, K. L., 2014, “Hueristics-Based Prototyping Strategy Formation -
Development and Testing of a New Prototype Planning Tool,” ASME Paper
No. IMECE2014-39959.
[23] Yang, M. C., 2005, “A Study of Prototypes, Design Activity, and Design Out-
come,” Des. Stud.,26(6), pp. 649–669.
[24] Yang, M. C., 2004, “An Examination of Prototyping and Design Outcom e,”
ASME Paper No. DETC2004-57552.
[25] Christie, E. J., Jensen, D. D., Buckley, R. T., Menefee, D. A., Ziegler, K. K.,
Wood, P. K. L., and Crawford, R. H., 2012, “Prototyping Strategies: Literature
Review and Identification of Critical Variables,” ASEE Annual Conference,
San Antonio, TX, June 9–12, Paper No. 3698.
[26] Menold, J. D., 2017, “Prototype For X (PFX): A Prototyping Framework to
Support Product Design,” Doctoral thesis, The Pennsylvania State University,
State College, PA.
[27] Menold, J., Simpson, T. W., and Jablokow, K. W., 2016, “The Prototype for X
Framework: Assessing the Impact on Desirability, Feasibility, and Viability of
End Designs,” ASME Paper No. DETC2016-60225.
[28] Gerber, E., and Carroll, M., 2012, “The Psychological Experience of Proto-
typing,” Des. Stud.,33(1), pp. 64–84.
[29] Jensen, M. B., Elverum, C. W., and Steinert, M., 2017, “Eliciting Unknown
Unknowns With Prototypes: Introducing Prototrials and Prototrial-Driven
Cultures,” Des. Stud.,49(1), pp. 1–31.
[30] Charmaz, K., 2014, Constructing Grounded Theory, Sage, London.
[31] Camburn, B., Dunlap, B., Gurjar, T., Hamon, C., Green, M., Jensen, D., Craw-
ford, R., Otto, K., and Wood, K., 2015, “A Systematic Method for Design Pro-
totyping,” ASME J. Mech. Des.,137(8), p. 081102.
[32] Lauff, C., Kotys-Schwartz, D., and Rentschler, M. E., 2017, “Perceptions of
Prototypes: Pilot Study Comparing Students and Professionals,” ASME Paper
No. DETC2017-68117.
[33] Deininger, M., Daly, S. R., Sienko, K. H., and Lee, J. C., 2017, “Novice
Designers’ Use of Prototypes in Engineering Design,” Des. Stud.,51(1), pp.
25–65.
[34] Beaudouin-Lafon, M., and Mackay, W., 2003, “Prototyping Tools and
Techniques,” The Human-Computer Interaction Handbook, J. A. Jacko and A.
Sears, eds., Lawrence Erlbaum Associates, Mahway, NJ, pp. 122–142.
[35] Hannah, R., Michaelrag, A., and Summers, J., 2008, “A Proposed Taxonomy
for Physical Prototypes: Structure and Validation,” ASME Paper No.
DETC2008-49976.
[36] Houde, S., and Hill, C., 1997, “What Do Prototypes Prototype,” Handbook
Human Computer Interaction, Vol. 2, Apple Computer, Cupertino, CA, pp.
367–381.
[37] Lande, M., and Leifer, L., 2009, “Prototyping to Learn: Characterizing Engi-
neering Students’ Prototyping Activities and Prototypes,” 17th International
Conference on Engineering Design, Design Processes, Palo Alto, CA, Aug.
24–27, Paper No. DS 58-1.
[38] Lim, Y. K., Stolterman, E., and Tenenberg, J., 2008, “The Anatomy of Proto-
types: Prototypes as Filters, Prototypes as Manifestations of Design Ideas,”
ACM Trans. Comp. Human Interaction,15(2), p. 7.
[39] Michaelraj, A., 2009, “Taxonomy of Physical Prototypes: Structure and Vali-
dation,” Master thesis, Clemson University, Clemson, SC.
[40] Friedman, K., 2003, “Theory Construction in Design Research: Criteria:
Approaches, and Methods,” Des. Stud.,24(6), pp. 507–522.
[41] Coughlan, P., Suri, J. F., and Canales, K., 2007, “Prototypes as (Design) Tools
for Behavioral and Organizational Change: A Design-Based Approach to Help
Organizations Change Work Behaviors,” J. Appl. Behav. Sci.,43(1), pp.
122–134.
[42] Thomke, S. H., 1998, “Managing Experimentation in the Design of New
Products,” Manage. Sci.,44(6), pp. 743–762.
[43] Drezner, J. A., and Huang, M., 2009, “On Prototyping: Lessons From RAND
Research,” RAND Corporation, Santa Monica, CA, accessed Feb. 24, 2018,
https://www.ra nd.org/content/dam/rand/pubs/occasional_p apers/2010/RAND_
OP267.pdf
[44] Simon, H., 1969, The Sciences of the Artificial, MIT Press, Cambridge, MA.
[45] Sch€
on, D. A., 1983, The Reflective Practitioner: How Professionals Think in
Action, Basic Books, New York.
[46] Latour, B., 1987, Science in Action: How to Follow Scientists and Engineers
Through Society, Harvard University Press, Cambridge, MA.
[47] Latour, B., and Porter, C., 1996, Aramis, or, the Love of Technology, Harvard
University Press, Cambridge, MA.
[48] Bucciarelli, L. L., 2002, “Between Thought and Object in Engineering Design,”
Des. Stud.,23(3), pp. 219–231.
[49] Bucciarelli, L. L., 1988, “An Ethnographic Perspective on Engineering
Design,” Des. Stud.,9(3), pp. 159–168.
[50] Bucciarelli, L. L., 1994, Designing Engineers, MIT Press, Cambridge, MA.
[51] Trevelyan, J., 2007, “Technical Coordination in Engineering Practice,” J. Eng.
Educ.,96(3), pp. 191–204.
[52] Trevelyan, J., 2010, “Reconstructing Engineering From Practice,” Eng. Stud.,
2(3), pp. 175–195.
[53] Dym, C. L., Agogino, A. M., Eris, O., Frey, D. D., and Lei fer, L. J., 2005,
“Engineering Design Thinking, Teaching, and Learning,” J. Eng. Educ.,94(1),
pp. 103–120.
[54] Vinck, D., Jeantet, A., and Laureillard, P., 1996, “Objects and Other Interme-
diaries in the Sociotechnical Process of Product Design: An Exploratory
Approach,” The Role of Design in the Shaping of Technology, J. Perrin and D.
Vinck, eds., European Commission Directorate-General Science, Research and
Development, Brussels, Belgium, pp. 297–320.
[55] Vinck, D., 2003, Everyday Engineering: An Ethnography of Design and Inno-
vation, MIT Press, Cambridge, MA.
[56] Vinck, D., 2011, “Taking Intermediary Objects and Equipping Work
Into Account in the Study of Engineering Practices,” Eng. Stud.,3(1), pp.
25–44.
[57] Star, S. L., and Griesemer, J. R., 1989, “Institutional Ecology, ‘Translations’
and Boundary Objects: Amateurs and Professionals in Berkeley’s Museum of
Vertebrate Zoology, 1907-39,” Social Stud. Sci.,19(3), pp. 387–420.
[58] Star, S. L., 2010, “This Is Not a Boundary Object: Reflections on the Origin of
a Concept,” Sci., Technol., Human Values,35(5), pp. 601–617.
[59] Henderson, K., 1991, “Flexible Sketches and Inflexible Data Bases: Visual
Communication, Conscription Devices, and Boundary Objects in Design Engi-
neering,” Sci., Technol. Human Values,16(4), pp. 448–473.
[60] Henderson, K., 1995, “The Political Career of a Prototype: Visual Representa-
tion in Design Engineering,” Soc. Probl.,42(2), pp. 274–299.
[61] Creswell, J. W., Plano Clark, V. L., Gutmann, M. L., and Hanson, W. E.,
2003, “Advanced Mixed Methods Research Designs,” Handbook of Mixed
Methods in Social and Behavioral Research, Sage, Thousand Oaks, CA, pp.
209–240.
[62] Maxwell, J., 2013, Qualitative Research Design: An Interactive Approach,
Sage, Thousand Oaks, CA.
[63] Lauff, C., O’Connor, K., Kotys-Schwa rtz, D., and Rentschler, M. E., 2015,
“Comparing Organizational Structures: Two Case Studies of Engineering
Companies,” ASEE Annual Conference and Exposition, Seattle, WA, June
14–17, Paper No. 13095.
[64] Lauff, C., O’Connor, K., Kotys-Schwa rtz, D., and Rentschler, M. E., 2014,
“How is Design Organized? A Preliminary Study of Spatiotemporal Organiza-
tion in Engineering Design,” IEEE Frontiers in Education Conference (FIE),
Madrid, Spain, Oct. 22–25, pp. 1–5.
[65] Law, J., 1987, “On the Social Explanation of Technical Change: The Case of
the Portuguese Maritime Expansion,” Technol. Culture,28(2), pp. 227–252.
[66] Suchman, L., 2000, “Organizing Alignment: A Case of Bridge-Building,”
Organization,7(2), pp. 311–327.
Journal of Mechanical Design JUNE 2018, Vol. 140 / 061102-11
[67] Czarniawska-Joerges, B., 2007, Shadowing: And Other Techniques for Doing
Fieldwork in Modern Societies, Copenhagen Business School Press, Copenha-
gen, Denmark.
[68] Spradley, J. P., 1979, The Ethnographic Interview, Holt, Rinehart and Winston
Publishing, New York.
[69] Corbin, J., and Strauss, A., 1994, “Grounded Theory Methodology,” Handbook
of Qualitative Research, Vol. 17, N. K. Denzin and Y. S. Lincoln, Sage, Thou-
sand Oaks, CA, pp. 285–305.
[70] Charmaz, K., 2008, “Grounded The ory as an Emergent Method,” The Sage
Handbook for Qualitative Methods, Vol. 4, Sage, Thousand Oaks, CA, pp.
359–380.
[71] Miles, M. B., and Huberman, A. M., 1994, Qualitative Data Analysis: An
Expanded Sourcebook, Sage, Thousand Oaks, CA.
[72] Sutcliffe, A., and Sawyer, P., 2013, “Requirement s Elicitation: Towards the
Unknown Unknowns,” 21st IEEE Requirements Engineering Conference (RE),
Rio de Janeiro, Brazil, July 15–19, pp. 92–104.
[73] Rust, C., 2004, “Design Enquiry: Tacit Knowledge and Invention in Science,”
Des. Issues,20(4), pp. 76–85.
[74] Krishnan, V., and Ulrich, K. T., 2001, “Product Development Decisions: A
Review of the Literature,” Manage. Sci.,47(1), pp. 1–21.
[75] Ulrich, K. T., and Eppinger, S. D., 2008, Product Design and Development,
McGraw-Hill, New York.
061102-12 / Vol. 140, JUNE 2018 Transactions of the ASME
