The research presented here describes an industry case study of the use of immersive virtual reality (VR) as a general design tool with a focus on the decision making process. A group of design and manufacturing engineers, who were involved in an active new product development project, were invited to participate in three design reviews in an immersive environment. Observations, interviews, and focus groups were conducted to evaluate the effect of using this interface on decision making in early product design. Because the team members were actively engaged in a current product design task, they were motivated to use the immersive technology to address specific challenges they needed to solve to move forward with detailed product design. This case study takes the approach of asking not only what can users do from a technology standpoint but also how their actions in the virtual environment influence decision making. The results clearly show that the team identified design issues and potential solutions that were not identified or verified using traditional computer tools. The design changes that were the outcome of the experience were implemented in the final product design. Another result was that software familiarity played a significant role in the comfort level and subsequent effectiveness of the team discussions. Finally, participants commented on how the immersive VR environment encouraged an increased sense of team engagement that led to better discussions and fuller participation of the team members in the decision process.
In order to create an immersive experience, computer technology is designed to stimulate the human senses in ways that appear natural to the user. While implementations of virtual smells and tastes have received little traction, much has progressed with respect to stimulating the other primary senses: sight, hearing, and touch. Through the use of large projection environments or head mounted displays, projected stereographic imagery can fill a person’s entire field of view. Real-time tracking systems provide position and orientation data of the users in the immersive environment, allowing them to interact with objects in the scene using natural human motions. Correct visual perspectives are calculated and projected based on the tracking data provided of the user’s head. Dynamic 3D images update many times per second to provide a view of a three-dimensional virtual object from the user’s current viewpoint as they move through the space. Arms, hands, and other limbs can also be tracked to enable both natural and innovative interaction techniques with the computer-generated objects. Auditory stimuli can be provided through surround sound systems, giving the users additional information about what is happening in the virtual environment. Advances in haptic and touch technologies empower user understanding through force feedback-based interaction. Not only can the user see and hear the virtual environment, but they can also feel it. When combined with fast and efficient algorithms, the blending of these technologies creates new mediums where new product ideas can be generated, explored, and evaluated.
In efforts to bridge the gap between desktop computer-aided design (CAD) and fully immersive virtual environments, 3D design and visualization software packages have begun to incorporate immersive capabilities through software plugins. Designers and engineers can make precision design changes on the desktop and then move into the immersive environment to understand the implications of their proposed changes. In some cases, transitioning from the desktop environment to the VR environment requires only minimal effort on the part of the user.
VR technology is being used in several companies to evaluate visibility, operator/repair technician/assembly worker ergonomics, component packaging, and other product design issues [1,2]. Much of the published literature associated with industry use of VR in design focuses on describing a specific application or target domain [3–7], with an emphasis on technology contributions. The case study presented here seeks to better understand the realized and potential benefits of VR in an industrial context, focusing on the human aspects of the experience. The case study describes the firsthand experiences of an engineering design team as they conducted design reviews in an immersive environment as part of a larger product design effort. The visits to the VR facility were motivated by real design challenges that occurred within the course of the normal workload of this design team. The design team members were experts in their fields but they were not previously familiar with immersive technology and therefore they entered the experience as novices with respect to the use of VR for design decision making. Because the team members were actively engaged in a current product design task, they were motivated to use the immersive technology to address specific challenges they needed to solve to move forward with detailed product design. This case study takes the approach of asking not only what can users do from a technology standpoint but also how their actions in the virtual environment influence decision making. Through a series of observations, interviews, and focus groups, decision making benefits in VR were identified.
The paper proceeds as follows: Section 2 reviews relevant research in the use of VR for design. Details about the facilities, software, and study procedure are presented in Sec. 3. Section 4 reports on the qualitative results of the case study. Broader insights are described in Sec. 5. The paper concludes in Sec. 6.
As early as 1993, the potential of VR technology to improve engineering product and process design was being investigated . Two areas in the literature gained the most attention from researchers: virtual manufacturing and virtual assembly. Virtual manufacturing is a term used to describe the use of immersive technology to prototype manufacturing processes. Similarly, the term Virtual assembly describes the use of immersive technology to explore or develop assembly methods. The motivation behind using VR to prototype manufacturing and assembly operations is the potential to feedback insights gained in the virtual environment to product designers to suggest modifications of the product geometry to reduce costs, improve ergonomics and safety, and improve operations before the product geometry is finalized.
In 1995, Cobb and associates  investigated the potential usefulness of VR in the United Kingdom manufacturing industry. Through a series of interviews, site visits, and demonstrative workshops, the authors concluded that while manufacturing professionals were optimistic about the potential of VR, they struggled to conceptualize practical use cases. In 1996, Shukla et al.  outlined current VR technologies and applications. Several industries actively investigating virtual manufacturing processes were described. More recently, Nee et al.  provided a detailed survey of augmented and VR technology with current practices relating to manufacturing. The survey indicates that the adoption of virtual manufacturing has matured greatly from 10 years prior.
Fewer reports in recent years have evaluated the efficacy of virtual assembly applications. Jayaram et al.  presented two case studies investigating the usefulness of virtual assembly with complex industry-grade geometry. The software, vade, allowed for interactive component manipulation. For each case study, the authors viewed videos and discussed existing assembly methods with engineers and managers. Next, the assembly procedure was programmed in the software and the CAD was exported into the virtual environment. Finally, manufacturing engineers evaluated the assembly process using the simulation. The differences between the virtual assembly simulation and the real life assembly were analyzed. In both cases, the software was of sufficient fidelity to efficiently evaluate the assembly processes. The authors described a large gap between simple proof-of-concept applications and those that are fully capable of contributing to decision making in industry.
Later in 2013, Fletcher et al.  investigated the use of a haptic device in VR to simulate a process planning system. The literature revealed that existing virtual machining environments only fulfilled some of the process planning activities. To this end, the authors developed a VR application called happ. The software allowed the user to simulate material setup, the machining activity, and the tear down procedure. A variety of information about the process is captured and logged during the simulation. Five expert process planners were asked to use the software to generate process plans for three parts of varying complexity. The automatically generated plans were analyzed through a peer review and an optimal plan was identified. The optimal plan was then given to a shop floor technician who manufactured each component. The technician was able to successfully follow the plans finding them to be an accurate representation of the machining process.
In both prior studies, the focus of the evaluation was on determining the extent to which the immersive experience provided sufficient fidelity to support decision making. The research presented here does not focus on identifying limits to the technology. We are not concerned with the question of how much fidelity is needed to achieve reliable results but rather our goal is to ask how does the use of this technology impact decision making in product design teams. We designed and implemented a controlled case study to explore the research question. The methods, results, discussion, and conclusions are presented in the following sections.
The study consisted of three discrete stages (Fig. 1). First, individual interviews with members of the design team were conducted. Next, the design team was invited to hold three design review sessions in an immersive environment. The timing of the design reviews was driven by the needs of the design team as they progressed through the design process in their daily tasks. As design issues came to the team, the design lead coordinated with the researchers to schedule a virtual design review in the immersive environment. Directly after each design review, the team participated in a focus group. Lastly, a final focus group was carried out to complete stage three.
Participants: Five male engineers from a hydraulic pump manufacturing company participated in the study. These five individuals were tasked with a major redesign of one of the company’s existing products. The individuals ranged in age from 31 to 42 with an average age of 35. One of the team members was the team lead and the others had various engineering responsibilities related to design and manufacturing of the company’s products. The majority of participants had been in the design and manufacturing industry for more than 7 years. None of the participants reported having experience with VR prior to the study.
Software: There are many VR software platforms developed by the research community, but only a few commercially available CAD software platforms that include the ability to display in stereo on multiple screens with position tracking capabilities. Teamcenter lifecycle visualization 9.1 from Siemens PLM Software  is a fully functional digital modeling software package that supports immersive viewing and interaction in a virtual environment. This was a logical choice for the software for the case study since Siemens was the standard adopted throughout the company for digital modeling. Members of the design team were extremely familiar with the desktop version of the software, but they had no experience with the immersive capabilities. A simple software plugin relied on a configuration file that was set up to correctly interface with the projection screens and position tracking hardware available in our facility. Within the immersive mode, multiple techniques for navigation and component manipulation were available. A menu system was displayed that provided user control over actions and modes. A Nintendo Wii Remote® (Fig. 2) was used as the input device for selection and manipulation of objects and selecting modes from the menu system.
Facilities: The study was carried out at three locations. The initial interviews were held in a conference room at the design team’s primary place of work. All three design reviews were conducted in a three-walled immersive projection environment called METaL (Fig. 3) located at Iowa State University. The post review focus groups and final focus group (stage 3) were completed in a conference room near the VR facility.
METaL consists of three projectors presenting stereographic imagery on two walls (4 m × 3 m and 3 m × 3 m) and a floor (4 m × 3 m). An infrared-based optical tracking system allowed the position and orientation of one users head and input device to be tracked within the space in real time. Other participants wear stereo glasses and view the same scene as the tracked user; however, the view projected on the screens only changes in response to actions by the tracked user. A drawback of these projection systems is that only the person with the tracked glasses sees an accurate perspective projection. Others in the facility see a slightly distorted view. A surround sound system provided audio feedback within the interaction space.
A set of individual interviews were conducted to understand the perceived benefits of using VR in a design process (Table 1). Any existing knowledge or experience with VR technology and applications was noted. Participants were asked questions about their roles in the product design process with special attention given to technical tasks (e.g., CAD software). The initial interviews were audio recorded for analysis.
The design team conducted three immersive design reviews of a new product in development. The first review was held approximately 1 month after the initial interviews (Sec. 3.1). Subsequent reviews were conducted between 1 and 2 months apart. Prior to each review, the researchers met with the design team to establish objectives for the immersive reviews. As past research suggests, individuals with limited VR experience find activity planning challenging [9,15]; therefore, the researchers helped scope the goals of each session to ensure that they were attainable given the capabilities of the current software. Additionally, the design team was given a brief tutorial on how to use the software’s immersive mode before the first design review.
For each session, the team arrived with the geometry, stored on a flash drive, which they loaded onto the VR laboratory computer. In order to maintain confidentiality, the VR laboratory was vacated and only the design team and the researchers were present during the sessions. At the completion of each session, the geometry was removed from the VR lab computer. The team spent 90 min per session in the immersive environment. Researchers observed participants’ interactions throughout the review and were available to answer any questions regarding the use and capabilities of the system.
Following each design review, the team participated in a focus group to identify salient qualities of the team’s experience. Questions investigated the advantages, disadvantages, and important aspects of their experiences relating to decision making. Participants were encouraged to describe their experiences in narrative form through a semi-structured interview protocol (Table 2). Comments were collected from all participants. Each focus group was audio recorded for analysis.
Final Focus Group.
The final focus group examined how the use of VR influenced decision making throughout the design process. Additionally, while the previous focus groups concentrated on specific design review experiences, the final focus group examined how their experiences in VR impacted other design activities (see Table 3). Again, all participants provided comments.
Data collected from the observations, interviews, and focus groups were analyzed from a bottom-up perspective. A within-case analysis [16,17] was performed for each immersive design review (Secs. 4.2–4.4). Next, overarching themes were extracted through across-case analysis, as described by Ayres et al. , in Sec. 5. Salient insights are reported in the order observed.
The goal of the initial interviews was to understand participants’ perceived usefulness of VR and how it may influence their experiences in VR. None of the participating design team members cited having previous experience with VR technologies or applications. Two participants mentioned having moderate to advanced expertise with multiple CAD software packages. One question asked participants to postulate about potential use cases for VR in product design. Without any previous experience with VR technology, it was challenging for participants to generate use cases, which is consistent with past research [9,15]. However, several potential use cases emerged. The potential to investigate assembly procedures was reported by all five participants. Three participants described scenarios in which component animations could help the team understand the spatial relationships during product interactions. Two participants described the perceived benefit of visualizing an operator’s assembly station at true scale. Participants imagined being able to interactively walk through a proposed assembly sequence in context in the virtual environment. One participant suggested that being able to simulate low clearance tolerance stack-ups would be desirable. The initial interviews provided a perspective for collecting and analyzing the data from the study.
Design Review 1.
For the first design review, the team wanted to better understand the spatial relationships between components during the engagement of two critical subassemblies. Some of the part geometry had been redesigned and the team was not sure if an assembler could continue to use simple visual confirmation to guide the assembly of the two subassemblies or if a physical guide, requiring change to the geometry of one part, was needed. This was a critical decision in the design process. Typically, this question would be answered at the prototype build stage, after a physical prototype had been built. Understanding the assembly of these two parts very early in the design process could avoid the need for expensive tooling redesign at a later date. To begin, one of the researchers, familiar with the software, helped load the product geometry into the immersive environment. The design team stepped into the immersive space and stood spread out staring at the front-most wall. For the first 10 min, members of the design team stood still while discussing product features using primarily pointing and hand gestures. Soon after, the team member wearing the tracked stereo glasses (driver) began to explore the capabilities of the system by walking around to gain better perspective views. Team members without tracked glasses only moved to step out of the way of the driver. However, after 15 min, participants began crowding around the driver in an effort to share the viewing perspective. For the most part, the team remained in this configuration for the rest of the review. Occasionally, participants switched glasses to ensure all had a chance to experience the position tracked viewing perspective.
The team used an axis-constrained component manipulation feature to simulate the engagement of two subassemblies. The driver selected one assembly for manipulation and moved the Wii Remote about the space while describing the assembly questions and design concerns. The head-tracked stereo glasses were exchanged a few more times before the design questions were answered. The team answered their design questions faster than they had originally anticipated. The immersive experience confirmed that a visual confirmation was still appropriate and that no additional geometry modifications were required to facilitate the assembly. Notes about decisions and other design considerations were captured by the team lead using a cell phone and emailed to the rest of the team after the review. With their decision goal accomplished, the team began to explore other design issues. Numerous unscheduled conversations began which focused on other aspects of the product assembly process. Team members posed questions about potential tooling and environmental factors. The 3D visualization was leveraged to evaluate potential solutions to new inquiries on the spot. By the end of the first design review, participants were moving more naturally about the environment and leveraging multiple perspectives by walking, tilting their heads, and leaning down. After the review, the team and researchers walked to a conference room for a focus group session.
Several major themes emerged from the focus group discussions. The ability to view the product at true scale was vital for decision making. This was especially important in this case since the size of the product being examined was larger than what could fit on a typical computer monitor. Participants commented, “Looking at certain components [in CAD] they look one size, but they are actually another size.” Participants described instances in which seeing the product immersively improved their understanding of how components were laid out spatially and how each component interacts with one another. Because steps in the assembly process were complex, understanding specific component visibility from the assembler’s perspective was critical. Interacting with the components at close to true scale also gave participants a stronger kinesthetic sense of potential operator–product interactions. One engineer mentioned: “It gave you a perspective of how far to kneel down to see that engagement.” Furthermore, being able to manipulate subassemblies freely, a process difficult with CAD software on the desktop, enabled participants to better describe potential assembly scenarios in a natural way.
Participants expressed an increased ability to communicate geometry-specific insights. Instead of verbally describing a perspective-specific viewpoint (e.g., “housing assembly from above”), the tracked glasses could be handed to other participants to share the experience of specific viewpoints. One participant described their experience: “Especially the view that you were bringing up while thinking about the clearances and the space within the unit. I didn’t have that same perspective, but when you mentioned that and then I got a chance to look at it I thought—Oh yeah, now I can see it.” Participants quickly found that referencing objects in the virtual environment through pointing and hand gestures were difficult because of varying visual perspectives. As one participant articulated, “my hand was pointing here, his hand was pointing there” (different spatial locations). However, this deficiency minimally impacted communication. Because everyone was intimately familiar with the geometry, components could be verbally identified using short domain-specific phrases.
Design Review 2.
For the second design review, held approximately 2 months after the first, the team proposed two questions for investigation. First, with the overarching design goal of minimizing product size, the team had concerns regarding the working clearances of internal components. More specifically, the team wanted to understand the clearances between components during different stages of operation. If the working clearances were too tight, then the product might experience unnecessary wear. On the other hand, the team was also constrained to fit the product within a well-defined overall product envelope so they were trying to fit all the parts together as closely as possible. Again, this was a critical decision in the product design process. The second inquiry involved a proposed method of inserting one subassembly into another.
During the initial geometry loading phase, participants requested taking a more active role in the preparation. Upon this request, researchers stepped away from the workstation and two design team members, most familiar with the desktop version of the software, began configuring the experience. Because the Siemens software contains both the desktop version and the immersive plugin, the team members found that they could easily stop the immersive display, go back to the familiar desktop display, change geometry, bring in new parts, set up constraint axes, etc. then engage the immersive display and return to METaL to continue their investigation. Throughout this process, the team discussed which perspectives and geometry orientations would be most helpful in answering their questions and then they modified the experience accordingly.
After spending 5–10 min configuring the application, the design team entered the virtual environment. While participants initially dispersed themselves evenly about the space, they quickly regrouped around the person with the tracked glasses (Fig. 4). The discussion started with the driver describing the salient concerns. Hand gestures were used to describe the motion of one component within another.
The team appeared to be more comfortable with the workspace and tended to interact with the geometry from new perspectives. For the majority of the first review, the front projection screen was heavily utilized; however, the second wall and floor saw much more use during the second review. Two team members remembered Wii Remote button mappings for program features and used them more often. At one point, the team members noticed that one section of a component appeared thinner than they had realized. After the session, they performed a more detailed analysis of the stresses in the part and eventually redesigned the component. Although this delayed the design process somewhat, the team felt that a critical issue was addressed that became apparent only during their immersive environment session. The researchers anticipated seeing an increased amount of sharing the tracked glasses; however, only a slight increase was observed. For the majority of the session, the two team members leading the review tended to wear the tracked stereo glasses.
On three separate occasions in the course of the 90-min session, the team broke out of the immersive experience to make adjustments to the product configuration using the CAD software in the traditional desktop mode. In these instances, one member from the team stepped out of the space and sat down at the nearby workstation. A few moments later, the adjustment was made and the team was back at work in the immersive environment. While many of the adjustments could have been made using the software’s immersive menu, participants, being familiar with the desktop version, found it simpler to pause the experience and make the adjustments from the desktop. The transition between the desktop and immersive environment required little effort. Within the first 20 min, the team had answered their primary questions and was ready to move on to the second inquiry.
For the second objective, the team wanted to investigate a proposed assembly method involving two subassemblies. Through a series of translations and rotations across multiple axes, the smaller of the subassemblies needed to be inserted into the larger. To this end, the team configured the software such that the two subassemblies could be manipulated as grouped parts in the VR environment. Next, using the immersive menu, collision detection was enabled. Team members took turns attempting to complete the assembly operation by manipulating the Wii Remote and moving around the virtual product. When collisions occurred, the colliding component appeared highlighted in red. No haptic or audio feedback was rendered. Because of tight clearances, participants struggled to complete the assembly while manipulating the Wii Remote. While the virtual assembly experience was not realistic enough to fully address the questions, the experience illustrated the body and arm postures that would be required by an operator performing this assembly operation. One participant reported that the experience “reinforced the complex movement required to get that [subassembly] installed.” Based on the experience, the team made plans to further evaluate the assembly method using physical models to address ergonomic concerns.
Many of the same insights from the first design review re-emerged during the second focus group. Participants commented on how the immersive visualization at true scale provided a stronger understanding of component relationships, especially helpful when understanding clearances. Free form interaction was also cited as giving valuable assembly feedback, even though the collision detection “didn’t have the feel through the hand.” The use of the Wii Remote for interaction also made manipulation feel unnatural. One participant hypothesized that a glove device may solve the problem: “If I had a glove instead of a wand [Wii Remote], I may be able to grab the part better.”
The team, as a group, reported that they worked together more effectively during the second review. One of the team members mentioned: “I think we passed the glasses around a little bit more. Or someone would notice something and say—hey what do you think?” As the review progressed, participants used the facilities and program features more.
Most notably, participants appreciated the ability to come into the environment and get to work more quickly. One team member declared: “The wow factor was gone, I felt like it was all business, jumped in [and] looked at what we needed to and got that done.” Participants also acknowledged that they felt more capable with the VR system and the increased confidence lead to a more directed design review. Three participants expressed that having the initial experience in VR helped them to prepare and execute the second review more effectively.
Design Review 3.
While the previous two design reviews investigated product-centric questions, the third review focused on the design of an assembly line. The team designed an innovative assembly line and was unsure whether there would be enough space at each station for the operator and the tooling. They wanted to understand how the new assembly line would impact interactions between the operator, product, and tooling. This assembly line presented a significant deviation from existing assembly lines within the company. If this design proved successful, it could have major implications for future assembly. Understanding the layout of the stations within the assembly line from visibility, ergonomic, and reachability perspectives was crucial for developing the design.
Geometry of a partial assembly line was loaded into the virtual environment. The assembly line consisted of 10 to 12 benchtop stations. When possible, the pump geometry was placed in context with the assembly line. The design review began with a manufacturing engineer stepping into the virtual environment with the team. The first few minutes were spent looking around and becoming acquainted with the layout. For each station, the driver verbally described each station’s purpose. Hand, arm, and body gestures were used to communicate the interaction processes.
Many times throughout the review participants placed their hands at specific locations in the environment as if to gauge the distance between two points. It is possible that combining the visual information (what they saw) with kinesthetic information (what they felt) provided an enhanced sense of spatial relationships. At one point, someone asked: “How far [away] are the bins?” The driver walked up to the bench and reached out to touch virtual objects then responded: “about twelve to fourteen inches.” A while later, another driver placed his hands on the benchtop of one station and commented: “Those [bench tools] aren’t going to clog up the workspace as much as I thought.”
While the primary goal of the review was to evaluate the assembly line, multiple product-centric questions arose. Because the product geometry was loaded in context with the assembly line models, participants walked over to the product as they would in real life. The team commented that it was nice to have the flexibility to view multiple models within the space because it allowed them to pursue a variety of topics without leaving the virtual environment. Upon completion of the third design review, participants followed the researchers to a conference room where the focus group was conducted.
The focus group began with a discussion surrounding a key finding from the design review. Within the immersive environment, the team found an issue with the placement of a particular assembly tool. The tool was mounted to the workbench between two workspace areas. The assembly procedure required the operator to be at one location and reach across the tool to access a parts storage bin. Before the design review, the team believed the placement of the tool was acceptable; however, after experiencing the interaction in VR, they decided that the assembly station must be modified.
Participants reported experiencing several new benefits unique to the third design review. Seeing the assembly stations at true scale provided participants a better sense of distance within and across the workstations. One participant compared their experience with CAD software to their experience in VR: “In 3D models [CAD] you can take a measurement of how far the distance is, but when you have the pump [occupying physical space], it actually makes a difference…because you have to get in, then walk around it.” Multiple participants found that being able to move freely and naturally through the assembly process provided, “a whole new perspective” on how operators and parts move down the line. Without VR, visualizing this process is left to the imagination. Walking through interactions mentally can be very different compared to physically performing the interaction in VR. One participant explains: “You can always picture it in your head and imagine how it’s going to move, but until you see it in VR, it’s a different experience altogether.”
The immersive review experience also had limitations. All participants reported wanting to interact with the product in the context of each station. While portions of these interactions are available in the software, they were not configured at the time of review. One participant described specific interactions: “Yes, It would have been nice to see the unit at each station to get a sense of what that would be like. Push it, and pull it back.” Seeing the product in motion with the assembly line would have added to the team’s understanding of the overall assembly procedure.
Participants found their experience with the third design review to be notably different compared to the first two reviews. The first reviews leveraged a product-centric perspective, while the assembly line focused on the process, tooling and bench configuration. Because the assembly line was large, the geometry was viewable on all three screens regardless of viewing perspective. The increased viewing area allowed participants to spread out and form groups to discuss various concerns. Even though a single perspective was rendered on the display, participants felt like the nondriving perspective was useful. One participant noted that communication was easier with the assembly line than it had been with the pump: “Two people could be looking at one part and two others could be talking about something else. It wasn’t ‘Hey look at this’ and crowd and hover around somebody’s shoulder. It filled the whole space and we were able to go off on our own and do our little investigation and have our own conversations.” Effectively communicating an idea with other team members did not always require sharing the tracked glasses.
One participant found that the VR experience encouraged the team to be more engaged compared to traditional design reviews. The day before the third immersive review, the team held a similar meeting in a conference room at their workplace. The team lead explained: “I thought it was funny, that we went through the same meeting yesterday, with everybody’s laptops open, doing other work on the side and not fully engaged, and [got] completely different results.” Multiple participants posited hypotheses as to why the virtual review was more engaging. One participant suggested: “It’s interactive. You’re there. You’re in it. Versus you’re sitting in a conference room around a table [where] it’s too easy to have your laptop open and do some other things. You’re standing up, there’s no surface for your laptop, you’ve got glasses on. It’s just visual and immersive.”
Toward the end of the focus group, one participant began describing how their experience with the third design review will influence not only questions about the current design but will also inform future directions. One of the manufacturing engineers stated: “Experiencing it in VR is definitely going to put me ahead of the game. When it comes to going to the supplier, I’m not going to be surprised in what I saw. I have clear expectations of it now.” The participant continued by describing how their findings from this session will scale to extending the design. Thinking ahead to future designs is easy when you have already seen it: “I already feel like I’ve stood at station 10 and station 12.”
Final Focus Group.
A final focus group was conducted after the third immersive design review to understand how the use of VR influenced the overarching design process. The focus group began with a summary of the design reviews. Objectives and resulting outcomes were discussed (Table 4). For the first review, the use of the virtual environment validated their existing decision about the visibility of components during the engagement of two subassemblies. The team investigated tight operating clearances using section views during the second visit. Based on that review, significant changes were made to the design. Before the second review, the team admitted to being, “completely ignorant of the issue” and they were glad to have discovered it. For the third review, participants found that the location of a particular assembly tool created an awkward and suboptimal interaction. Again, based on their experience with the assembly line in the virtual environment, changes were made to the assembly station.
The design review outcomes raised the visibility of using VR in product design throughout the organization. Internal efforts were made to disseminate the early discoveries and experiences; however, participants found it challenging to describe the immersive experiences themselves: “I think we’ve done a good job explaining the value…, but it’s very difficult explaining the experience itself.”
To close, participants were asked when, in the design process, they thought VR would be most influential. The team hypothesized that the use of the technology could happen at different stages throughout the design process. During early concept generation, frequent immersive design reviews could help them iterate on product-centric ideas. Later on, as product geometry became more refined, the manufacturing design team could consider assembly tooling and processes leveraging assembly station geometry and feed this information back to the designers if necessary. At this stage, the use of VR by the manufacturing design team would increase while the concept designers’ use would decrease. Finally, when nearing production, VR could be helpful for training assembly operators. At this stage, VR would be used less frequently by the manufacturing engineers; however, one participant suggested that the technology might be useful to better understand changes to the assembly line that happen throughout the manufacturing life cycle.
The ability to view and interact with product (pump) and environment (assembly line) geometry at true scale added significant benefit to the team’s design efforts. The team approached each design review with specific questions and was able to effectively investigate them in the virtual environment. In the first design review, viewing the pump at true scale helped the team understand critical viewability concerns during subassembly engagement. Natural interaction with the Wii Remote provided the team with kinesthetic and ergonomic information regarding operator movement. Applying section viewing planes in the second review enabled the design team to understand the operating clearances in real size. As a result of the third review, an assembly station’s layout was modified after finding that it made important processes inconvenient for operators. Participants reported that their experiences in VR provided them with a stronger sense of the spatial relationships between product components as well as the interaction space around the assembly line.
Participants found that interacting with the geometry using the Wii Remote was helpful, but was too awkward and unnatural to fully investigate their assembly inquiries. The collision detection experience was not robust enough to be useful at this point.
Having some familiarity with the software, in the desktop version, supported a smooth transition to the immersive experience. In this study, the team’s partial familiarity with the software supported an easy transition between CAD software on the desktop and the immersive experience that allowed them to spontaneously explore issues that arose during the review. In the immersive environment, they did not hesitate to explore additional design challenges because they had confidence that they could configure the product geometry very quickly into the form needed for their use. Loading in new geometry, selecting various parts to view, etc. was virtually seamless with no geometry preprocessing needed. This proved to be very beneficial. The time investment of learning new interfaces often acts as a barrier of entry for many new technologies. While the immersive menu provided many options, the design team preferred pausing the experience, modifying the application from the desktop, and then re-entering the experience. This familiar interface allowed the team time to concentrate on the task at hand more quickly. More advanced capabilities provided in the immersive menu could be explored as the team became more comfortable in the environment.
Using the virtual environment provided an increased sense of team engagement. Traditionally, design teams huddle around conference tables with laptops, cell phones, and paper notebooks while one person manipulates the design on a large 2D screen at best. Maintaining team engagement and attention becomes particularly onerous when competing with distractions from electronic devices. The virtual environment provided the design team with an opportunity to step away from the conventional conference room and into a design space with fewer distractions. Multiple team members reported noticing increased team engagement during design discussions within the immersive environment.
This paper presents a case study to investigate early design decision making in VR. A group of design and manufacturing engineers, new to VR, were invited to conduct three design reviews in a projection-based immersive computing facility. During the course of the design reviews, participants investigated numerous questions surrounding a new product design. Participants found tremendous value in being able to view and interact with the geometry at true scale in a virtual environment. Most notably, participants reported gaining a better understanding of the spatial relationships between product components as well as the interactions required to assemble the product. Their VR experience helped guide existing and future design directions. Two of the three immersive design reviews resulted in considerable changes to the design.
The emergence of commercial CAD software that has the ability to support interaction in an immersive environment greatly facilitated the use of VR in product design decision making. Building from existing knowledge of the CAD software and its capabilities, design team members were able to move between the desktop environment and the immersive environment seamlessly. The ability to interact in 3D space with virtual products that can be shown at real scale has been shown in this study to be a valuable tool for the design team. Finally, interacting in the immersive environment engages design team members more actively in the discussion of design challenges and solutions when compared to the rather passive conference room environment of traditional design reviews. In the future, additional capabilities that provide haptics and better collision detection will enhance the immersive design review experience even further, contributing to even greater use of virtual prototyping for design decision making.
This material is based upon work supported by the National Science Foundation under Grant No. CMMI-1068926.