Image courtesy of SUBARU

SUBARU harnesses the power of VR for user research

August 1, 2022
Until recently, if automakers wanted to find out what customers thought about a prospective car design or new design proposals, they’d have to create a physical model so people could see it in person.

On top of the cost of creating and transporting these models, this approach forced car companies to accept certain restrictions. For example, they’d have to use a secure site to ensure confidentiality.

At SUBARU, they are experimenting with a new method to eliminate these limitations using game engine technology and VR for user research.

Bringing game dev skills to automotive

Kotaro Uki is one of a new generation of workers who bring a background in game development to new industries. Before joining SUBARU, he spent about a decade working on console games as a CG movie and effects designer on franchises like Time Crisis.

As game engine technology transforms traditional workflows in everything from AEC to film and TV, game development skills are increasingly in demand. That means career trajectories like Uki’s are becoming increasingly common.

Now, Uki puts the skills and experience he gained in the games industry to use on research and development at the Japanese car giant, using Unreal Engine to push automobile design forward.

Uki explains that the car design development process at SUBARU can be roughly divided into five stages: research, sketchwork, modeling, evaluation / visualization, and design review. “Though it is well-known that digital technologies are used for modeling and visualization, SUBARU also actively uses these technologies for a user research process called ‘the clinic’ in which we use the design under development to investigate how the target user feels and what design options they prefer,” he says.

Previously, SUBARU produced full-scale clay models for the clinic. Because those models had to be transported to a secure location, the design development process effectively had to pause until the model reached its destination.

“Also, we had to accept compromises,” says Uki. “For example, we sometimes produce expensive additional prototypes to make the headlamps and wheels look as much like the product as possible.”

In situations where there was not enough time or budget to use the first choice of materials, those elements of the vehicle would have to be substituted for ones made of paper and film.

In a bid to overcome these challenges, SUBARU developed an application that can reproduce all the processes of the clinic using VR. The technology was developed in cooperation with historia, one of the leading Unreal Engine content developers in Japan.

In the VR process, a user wears a head-mounted display and answers questions in front of a digital prototype model. The team developed their own interfaces that enable the user to complete the questionnaires in a comfortable way—even in VR.
Using digital versions of vehicle models has made it possible for SUBARU to easily reproduce parts and textures that had been impossible to produce in the physical clay models. This approach has also eliminated the need to prepare a special environment for confidentiality.

The numbers tell the story of how cost-effective this transition has been: SUBARU reduced design review costs to 1/7 of their original level and slashed lead times from six weeks to three days.

A deeper understanding of user preferences

SUBARU had another key reason for converting the clinic to a digital process. They were interested in exploring user’s preferences and understanding in greater detail how users assessed the designs of the cars.

To analyze these factors, SUBARU focused on the users’ posture and tracked where they were looking during the design evaluation. The idea is that it’s possible to get a more accurate picture of user preferences by evaluating information based on the location and direction of the HMD and VR controller, alongside their spoken feedback.

That kind of information can’t be acquired using a conventional approach based on physical models—you need the power of digital technology. In order to obtain this data, SUBARU and historia developed functionality in the VR application that would enable the team to assess the user’s posture while they are reviewing the design and identify the areas of the vehicle they are looking at. They also developed the functionality to visualize this data and connect it to the users’ survey answers.
This yielded some interesting results. The team spotted discrepancies between the survey responses and the users’ actual behavior—discrepancies that implied the conventional design evaluation process could be failing to detect the users’ true areas of focus during the design evaluation.

For instance, a user who answered that the tires were large and looked sporty was found to have spent very little time actually looking at the wheels. Instead, they had directed most of their attention to other parts of the car.

This VR application also has functionality to completely replay the user’s evaluation process, from what areas of the digital prototype car the user looked at and how long the user looked to how they appraised the car afterwards. This enables SUBARU to provide far more detailed feedback to designers and modelers than was previously possible.

Though the results suggest SUBARU can gain a deeper understanding of users’ preferences using the VR method, a challenge remains.

That challenge is to understand the feelings and emotions users experience when evaluating designs. The answer to this question will be a key element in working out how users make decisions on what they like and don’t like. SUBARU is conducting further research and studies to answer this.

Unreal Engine efficient automotive design

SUBARU has been using Unreal Engine in its design processes since 2016. “One of the reasons we chose Unreal Engine over other software and game engines was because of the Blueprint visual scripting system,” says Uki. “The advantage of Blueprint is that you can intuitively build interactions.”
Image courtesy of SUBARU
Blueprint enables designers to use a range of tools that would ordinarily be the preserve of programmers. Adding interactivity and other functionality to designs can be achieved without having to rely on the technical skills of other team members.

"Another reason is because of the public availability of assets such as Automotive Materials and those in the Quixel Megascans libraries,” says Uki. “These assets are particularly useful when creating CG scenes that leverage real-time ray tracing.”

Asset packs like Automotive Materials that can be used in real-time automotive scenes and applications are regularly released on the Unreal Marketplace, while the Quixel Megascans library is continually updated with photorealistic materials and assets.
Outside of the clinic and visualization, SUBARU has started using Unreal Engine to study human-machine interfaces (HMI). They are also leveraging the engine to evaluate vehicle designs in an environment where things such as weather dynamically change—something that is difficult to reproduce using VRED.

Uki believes switching the approach of their design development process to a real-time approach powered by Unreal Engine has had a significant impact at SUBARU. "Developing new designs with Unreal Engine has not simply improved efficiency with faster iteration, but has also provided an opportunity for SUBARU to broaden its perspective beyond traditional molding and styling designs by automotive companies. We expect this change in approach to bring even more value in the future!"

    Get Unreal Engine today!

    Get the world’s most open and advanced creation tool. 
    With every feature and full source code access included, Unreal Engine comes fully loaded out of the box.