Simulator Sickness: The Importance of Visual and Physical Synchronization in VR and XR Technologies

Abstract

Simulator sickness is a common condition encountered in both traditional simulation systems and virtual reality (VR) and extended reality (XR) applications. This condition arises from a mismatch between visual and physical motion, leading to symptoms such as nausea, dizziness, and fatigue. This article examines the role of synchronizing visual and physical motion in reducing simulator sickness and summarizes relevant scientific studies in the field.

Introduction

Simulator sickness is a condition caused by a mismatch between visual experiences and the vestibular system. This phenomenon was first explained by Reason and Brand (1975) through the Sensory Conflict Theory, which states that the discrepancy between the motion perceived by the eyes and the motion detected by the body's balance system results in discomfort. More recent studies, such as Stoffregen and Riccio (1991), introduced the Postural Instability Theory, providing a more detailed explanation of this phenomenon.

Ensuring the vestibular system is aligned with sensory input plays a critical role in reducing simulator sickness. Hettinger and Riccio (1992) demonstrated that improving the alignment between physical motion and visual feedback in simulator platforms significantly reduces user discomfort. Additionally, Lawson (2014) emphasized the importance of minimizing delays in motion and visual synchronization for optimal results.

Reducing simulator sickness through technological and experiential improvements has become a significant focus in both academic research and industrial development.

Causes of Simulator Sickness

1. Sensory Mismatch: The eyes perceive motion while the vestibular system signals that the body is stationary. This sensory mismatch is the primary cause of discomfort.

2. Visual Factors: Technical aspects such as refresh rates, field of view (FOV), and visual latency can increase the risk of simulator sickness.

3. Postural Instability: Users who experience instability or fail to maintain balance in the simulated environment are more likely to experience symptoms.

Synchronizing Visual and Physical Motion

One of the most effective methods to mitigate simulator sickness is synchronizing visual and physical motion. This approach supports the brain's perception of movement and eliminates sensory conflicts. For example:

• In a flight simulator, upward physical motion of the simulator should coincide with the visual depiction of an aircraft taking off.

• In a racing simulator, the platform should tilt sideways when navigating sharp turns.

MRS Aviation has developed innovative simulators that stand out in this area. The company's platforms, capable of 360-degree unlimited motion and integrated with XR technologies, aim to address simulator sickness effectively. These systems offer a realistic experience while minimizing the likelihood of sensory mismatch.

Technical Requirements

• Low Latency: Motion and visual synchronization delays should be less than 10 milliseconds.

• Motion Precision: Servo motors and optimized control software should provide rapid responses.

• Haptic Feedback: Vibration and pressure feedback can enhance user immersion and comfort.

Scientific Foundations

Key studies supporting this approach include:

1. Sensory Conflict Theory: The mismatch between perceived and experienced motion is the primary cause of discomfort. Synchronization eliminates this conflict.

2. Vestibular Rehabilitation Studies: VR gaming systems aligned with the vestibular system have proven effective in reducing discomfort.

3. Neurosurgical Applications: Advanced surgical simulators that synchronize visual and physical cues have demonstrated improved user comfort and performance.

Conclusion

Synchronizing visual and physical motion is an effective method for reducing simulator sickness. This approach has applications across various fields, from flight and racing simulators to surgical training. Emerging technologies, including low-latency motion systems and haptic feedback, further enhance these experiences. MRS Aviation's innovative simulators set a new standard in this field, aiming to make a significant impact both nationally and internationally. Future scientific studies can further refine theoretical and practical methods, potentially eliminating simulator sickness altogether.