Exploring Joint Effects of Locomotion Continuity and Wayfinding Assistance in Non-Embodied VR Game Navigation

Research Background and Issues

Identified Problems or Challenges

• The authors identified that the impact of different motion continuity (discrete optic flow and continuous optic flow) and path assistance tools on player navigation in non-embodied virtual reality (VR) games has not been thoroughly studied.
• Existing research primarily focuses on simple search tasks, with limited exploration of navigation performance in complex gaming environments.
• In the absence of path assistance, most users tend to lose their sense of direction, negatively affecting game performance and spatial learning ability.

Why This Issue is Important

• VR games require a balance between game tasks and navigation tasks, making the design of effective navigation support critical for player experience and game efficiency.
• A deeper understanding of the combined effects of motion continuity and path assistance can help design more effective VR game navigation schemes, with potential applications in health and education fields.

Research Motivation and Related Work

• Conduct systematic experiments to explore the combined effects of motion continuity (discrete optic flow and continuous optic flow) and path assistance (three conditions: no assistance, navigation line assistance, and automatic navigation) in complex VR game navigation scenarios.
• Drawing on real-world navigation theories and integrating the unique characteristics of VR, the study aims to provide guidance for optimizing VR game navigation design.

Solution

Proposed Methods or Solutions

• The authors proposed a 2×3 factorial model combining two types of motion continuity (discrete and continuous optic flow) and three types of path assistance (no assistance, navigation line assistance, and automatic navigation) to study their combined effects.
• A mixed-methods approach was employed for data collection and analysis, including quantitative research (e.g., game task performance, spatial learning ability, stress, usability, motion sickness) and qualitative research (thematic analysis).

Innovations of the Solution

• Investigating the mechanisms of the combined effects of motion continuity and path assistance rather than studying each factor in isolation.
• Systematically analyzing the impact of navigation behavior from the perspectives of exploration strategies, attention allocation, and spatial knowledge.
• Providing a basis for design applications to improve user experience and enhance the applicability of VR games.

Implementation Steps and Key Techniques

1. Experimental Design: Construct a closed VR environment and design combinations of two motion types and three path assistance conditions, resulting in six test scenarios.
2. Data Collection: Use game task tests (Test One), spatial learning task tests (Test Two), the System Usability Scale (SUS), the Simulator Sickness Questionnaire (SSQ), and electrocardiogram (ECG) data to record stress levels.
3. Interviews and Thematic Analysis: Conduct semi-structured interviews to explore participants' navigation experiences and challenges faced.
4. Quantitative and Qualitative Analysis: Combine non-parametric statistical tests and thematic analysis to uncover the mechanisms of the combined effects of motion continuity and path assistance.

Research Findings

Specific Findings

• Game Task Performance: Motion type and path assistance jointly influence performance. Automatic navigation assistance (W3) generally supports better task performance but interferes with spatial learning.
• Spatial Learning Ability: Navigation line assistance (W2) enhances spatial learning under discrete optic flow (DL) conditions but may hinder learning under continuous optic flow (CL) conditions.
• User Experience: Users prefer navigation line assistance (W2), which simplifies navigation tasks. However, the user experience evaluation of fully automatic navigation (W3) is lower than expected.
• Motion Sickness and Stress: Automatic navigation (W3) results in higher motion sickness, while navigation line assistance (W2) may indirectly cause disorientation, leading to a sense of detachment.

Advantages Compared to Existing Solutions

• Provides a comprehensive perspective for evaluating complex navigation scenarios rather than focusing solely on motion continuity or path assistance.
• Combines experimental and theoretical approaches to reveal the complementary and conflicting relationships between optic flow types and path assistance, offering optimization suggestions for design.

Experimental or Evaluation Results

• Under continuous optic flow conditions, users generally develop more comprehensive spatial knowledge (e.g., overall layout), whereas under discrete optic flow conditions, they rely more on path memory.
• Navigation line assistance serves as a usable landmark under discrete optic flow conditions but significantly affects users' attention allocation under continuous optic flow conditions, leading to incomplete spatial knowledge formation.

Limitations and Future Directions

• Limitations: The study does not fully resolve how to finely adjust path assistance design to balance the conflicts and complementarities between continuous and discrete optic flow. Additionally, it does not comprehensively address the nuanced dimensions of user experience.
• Future Directions:
  • Further research on the impact of navigation line design on visual attention and sense of direction.
  • Explore users' cognitive load and navigation behavior under specific task conditions.
  • Propose quantitative metrics for a more comprehensive evaluation of VR navigation experiences (including self-efficacy, coherence, etc.).

By exploring the combined effects of motion continuity and path assistance in VR navigation, this study provides valuable references for VR game designers to optimize navigation schemes and lays the groundwork for applying virtual environments in health and education fields.