From Slow-Mo to Ludicrous Speed: Comfortably Manipulating the Perception of Linear In-Car VR Motion Through Vehicular Translational Gain and Attenuation

Title of the Paper

From Slow-Mo to Ludicrous Speed: Comfortably Manipulating the Perception of Linear In-Car VR Motion Through Vehicular Translational Gain and Attenuation

Paper Information

• Research Domain: Virtual Reality (VR), perception manipulation, user experience in transportation and autonomous driving environments
• Keywords: perception manipulation, virtual reality, motion sickness, translational gain, autonomous vehicles, in-car gain, in-car attenuation, speed, in-car VR

Research Background and Problem Statement

• Identified Problems or Challenges:

  • Existing "motion-matching" VR experiences precisely map real vehicle motion to virtual environments, which reduces motion sickness (MS) but limits the design space of virtual applications.
  • Amplifying (gain) or reducing (attenuation) virtual speed could enrich travel experiences, but its effects on passenger perception and motion sickness remain unclear.
  • There is a lack of research applying translational gain/attenuation to real-world in-car motion, particularly regarding its impact on passive self-motion.

• Significance:

  • With the proliferation of autonomous driving and immersive devices (e.g., Holoride), exploring ways to enhance in-car VR experiences without significantly increasing motion sickness is crucial.
  • Gain/attenuation techniques could optimize productivity tasks, relaxation experiences, and gaming in differentiated ways.

• Research Motivation and Related Work:

  • Existing studies primarily focus on reducing motion sickness and have not thoroughly explored the applicability of perception manipulation techniques.
  • By introducing visual perception manipulation techniques (e.g., translational gain and attenuation), the authors aim to expand the potential of in-car VR experiences to suit various application scenarios (productivity, gaming, etc.).

Proposed Solution

• Methodology:

  • Designed a scheme to manipulate passengers' perceived visual speed in in-car VR through translational gain and attenuation, by modifying the ratio of visual speed in VR scenes to real vehicle speed (i.e., gain/attenuation values).
  • Validated the method through two real-world driving experiments, focusing on reading and gaming as application scenarios.

• Innovations:

  • Applied gain/attenuation to linear in-car motion for the first time, evaluating the effects of non-matching (non-1:1) motion on motion sickness, task performance (e.g., reading efficiency), and gaming immersion.
  • Clarified the applicability of gain and attenuation in different in-car VR scenarios, providing references for future designs.

• Implementation Steps and Key Techniques:

  1. Gain/Attenuation Operations:
     • Mapped various levels of virtual speed to real vehicle speed (~50 km/h) (gain range: 1.5-9.5x; attenuation range: 0.66-0.14x).
     • Gradually increased visual speed changes to reduce motion sickness.
  2. Experimental Equipment and Procedure:
     • Conducted experiments in real car scenarios equipped with VR headsets.
     • Test conditions included a standardized urban driving route (straight road sections).
  3. Experimental Parameters:
     • The first experiment (reading task) examined the effects of gain and attenuation on user perception in productivity environments; the subsequent experiment (gaming task) explored the impact of dynamic virtual speed changes on player immersion and gaming experience.

Research Findings

• Specific Results:

  • Gain significantly enhanced the perception of speed, distance, and excitement during travel but slightly increased cognitive load, reducing safety and relaxation.
  • Attenuation was more suitable for productivity tasks but slightly increased motion sickness.
  • Dynamic changes in visual speed need to align with actual vehicle speed changes to maintain immersion and comfort.

• Comparative Advantages Over Existing Solutions:

  • Explored novel perception manipulation designs beyond 1:1 motion matching, enabling high-speed virtual transport experiences even during low-speed urban driving.
  • Provided optimized design recommendations for different application scenarios (productivity and entertainment).

• Experimental or Evaluation Results:

  • Experiment 1 (Productivity Task):
    • Motion sickness primarily occurred under visual speed attenuation conditions, while symptoms were mild under matching motion and gain conditions.
    • Note-taking speed was fastest in matching motion, with attenuation and gain leading to slower speeds.
  • Experiment 2 (Gaming Task):
    • High visual gain (e.g., 9.5x) significantly enhanced gaming excitement, but dynamic speed changes (e.g., from gain to attenuation) slightly affected immersion.

• Limitations and Future Directions:

  • Limitations:
    • Experimental routes primarily consisted of straight road sections, without adequately considering complex motion patterns such as road turns.
    • Current tests were limited to low-speed urban driving scenarios (~50 km/h); future research should expand to high-speed or more complex driving conditions.
    • Productivity tasks were designed based on single-screen setups; multi-screen designs may yield different user experiences in the future.
  • Future Directions:
    • Investigate the effects of gain and attenuation during curved driving or at higher speeds.
    • Develop design guidelines for dynamic perception manipulation techniques, such as personalized adaptation and real-time adjustments.
    • Expand application domains: explore the potential of gain/attenuation in augmented reality (AR) scenarios to improve passenger experiences.