Person partially in real world and partially in virtual reality standing in doorway.

Is Virtual Reality Ready for Reality? Passability Judgments in VR vs. the Real World

Elliot Brynn in Tech & Innovation June 2025 • 5 min read.

"New research explores how accurately we perceive space and navigate virtual environments compared to real life, revealing insights into VR's potential and limitations."

Every day, we make countless judgments about space: how far away something is, how big it is, and whether we can fit through an opening. These judgments are crucial not just for everyday tasks but also for virtual reality (VR) experiences. As VR technology becomes more sophisticated and is used in training simulations and immersive entertainment, it's increasingly important to understand how well our spatial perception translates from the real world to virtual environments.

One critical aspect of spatial perception in VR is the ability to accurately judge 'passability' – whether we can physically pass through an opening, like a doorway or a narrow passage. This involves a complex interplay of perceiving size, distance, and our own body dimensions. If VR applications are to be truly immersive and useful, the spatial information they provide needs to closely match our real-world experiences.

Recent studies have shown that distance perception in VR can be underestimated, particularly when using head-mounted displays (HMDs). This can be due to hardware and software limitations. However, newer HMDs with wider fields of view are improving visual fidelity. This raises an important question: how do these technological advancements affect our ability to make accurate passability judgments in VR? Are we getting closer to a truly seamless and reliable virtual experience?

Do We Judge Passability Differently in VR?

Person partially in real world and partially in virtual reality standing in doorway.

A recent study from Clemson University investigated this very question, comparing passability judgments made in a real-world setting with those made in an immersive virtual environment. The researchers created a virtual replica of a real room, complete with an adjustable aperture (an opening that could be made wider or narrower). Participants were then asked to judge whether they could pass through the opening without rotating their shoulders, both in the real room and in the virtual one, experienced through an HTC Vive HMD.

The study aimed to determine whether there were significant differences in how people perceived and judged their ability to pass through the aperture in VR compared to the real world. The researchers carefully controlled the experiment, ensuring that the virtual environment was an accurate, scaled representation of the real room. This meticulous approach allowed them to isolate the impact of the virtual environment on passability judgments.

Here's a breakdown of the study's key elements:

Participants: A group of individuals with normal or corrected-to-normal vision.
Conditions: Participants experienced both a real-world condition and a VR condition using the HTC Vive.
Apparatus: An adjustable aperture (doorway) was used, with varying widths presented to participants.
Procedure: Participants judged whether they could pass through the opening without rotating their shoulders.
Data Collected: Aperture width, passability judgment (yes/no), whether participants walked toward the aperture to judge, and distance from the aperture when making the judgment.

The results of the study were surprising. While previous research has often shown underestimation of distances in VR, this study found that participants' passability judgments were comparable between the real world and the virtual environment. This suggests that, despite potential limitations in VR technology, our brains are quite good at adapting and making accurate assessments of our ability to navigate virtual spaces. However, there was one notable difference: participants in the VR condition tended to walk closer to the aperture before making their judgment. This indicates that while the accuracy of the judgments was similar, the level of certainty might have been lower in VR, prompting people to seek additional information before deciding.

The Future of VR: Improving Fidelity and Trust

This research offers valuable insights into the ongoing development of VR technology. While VR is becoming increasingly realistic, this study highlights the need to continue improving the fidelity of virtual environments to match our real-world experiences. Further research should focus on how factors like field of view, visual fidelity, and the presence of a virtual avatar affect our sense of space and ability to make accurate judgments in VR. By understanding these nuances, we can create more compelling, reliable, and truly immersive virtual experiences for everyone.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1109/vr.2018.8446189, Alternate LINK

Title: Towards Revisiting Passability Judgments In Real And Immersive Virtual Environments

Journal: 2018 IEEE Conference on Virtual Reality and 3D User Interfaces (VR)

Publisher: IEEE

Authors: Ayush Bhargava, Kathryn M. Lucaites, Leah S. Hartman, Hannah Solini, Jeffrey W. Bertrand, Andrew C. Robb, Christopher C. Pagano, Sabarish V. Babu

Published: 2018-03-01

Everything You Need To Know

What is 'passability' in the context of virtual reality, and why is it important?

'Passability' in virtual reality refers to the ability to accurately judge whether one can physically fit through an opening, such as a doorway or narrow passage. It's crucial because VR applications, especially training simulations and immersive entertainment, rely on realistic spatial perception. If users can't accurately assess passability, the sense of immersion and the utility of the VR experience are diminished. Ensuring accurate passability judgments requires a complex interplay of perceiving size, distance, and awareness of one's own body dimensions within the virtual environment. Missing is the haptic feedback and real-world consequences of errors.

How did the Clemson University study assess passability judgments in VR compared to the real world?

The Clemson University study compared passability judgments by creating a virtual replica of a real room with an adjustable aperture (doorway). Participants used an HTC Vive HMD to experience the virtual environment. They were then asked to judge whether they could pass through the opening without rotating their shoulders in both the real and virtual rooms. Researchers collected data on aperture width, passability judgment (yes/no), whether participants walked toward the aperture to judge, and distance from the aperture when making the judgment. The study aimed to determine if there were significant differences in how people perceived their ability to pass through the aperture in VR compared to the real world, carefully controlling the experiment to isolate the impact of the virtual environment.

What were the surprising findings regarding passability judgments in the VR environment using the HTC Vive, and what does it suggest about our adaptability?

The study found that participants' passability judgments were comparable between the real world and the virtual environment when using the HTC Vive. This was surprising because previous research often showed underestimation of distances in VR. It suggests that our brains are quite good at adapting and making accurate assessments of our ability to navigate virtual spaces, even with the potential limitations of VR technology. However, participants in VR tended to walk closer to the aperture before making their judgment, indicating a potentially lower level of certainty. While the accuracy was similar, the need for additional information gathering suggests a subtle difference in how confidently people assess passability in VR. Factors such as field of view impact these results.

What implications does this research have for the future development of VR technology, particularly in creating truly immersive experiences?

This research highlights the need to continue improving the fidelity of virtual environments to match our real-world experiences. While VR is becoming increasingly realistic, this study emphasizes the importance of further research into how factors like field of view, visual fidelity, and the presence of a virtual avatar affect our sense of space and ability to make accurate judgments in VR. By understanding these nuances, more compelling, reliable, and truly immersive virtual experiences can be created for everyone. Future development should focus on reducing the cognitive load required to adapt to VR's spatial discrepancies.

Considering the study's findings, what are some specific areas of VR technology that should be prioritized to improve spatial perception and trust in virtual environments?

Prioritizing improvements in several key areas of VR technology is essential. Firstly, enhancing the field of view in HMDs can provide a more natural and expansive visual experience, reducing the feeling of tunnel vision often associated with VR. Secondly, increasing visual fidelity, including resolution and realistic rendering, can improve depth perception and reduce the disconnect between the virtual and real worlds. Lastly, exploring the impact of virtual avatars and their embodiment on spatial perception could help users feel more present and confident in their judgments. Further research should also focus on haptic feedback to enhance the sense of touch and presence.