Time-of-flight imaging in fog using multiple time-gated exposures

Area of Science:

• Computer Vision
• Optical Sensing
• Environmental Monitoring

Background:

• Fog significantly degrades the performance of optical sensing systems, particularly for depth and intensity measurements.
• Existing time-of-flight (ToF) techniques struggle with scattering effects caused by atmospheric particles like fog.
• Accurate environmental perception is crucial for applications such as autonomous driving and robotics.

Purpose of the Study:

• To develop a robust time-of-flight (ToF) measurement algorithm capable of accurate depth and intensity reconstruction in the presence of fog.
• To address the limitations of current ToF systems in adverse weather conditions.
• To enable reliable environmental sensing for critical applications.

Main Methods:

• Proposed a novel algorithm utilizing multiple time-gating exposures.
• Incorporated a dedicated time-gated exposure for estimating fog's scattering properties.
• Employed a physics-based model to reconstruct depth and intensity from remaining exposures after scattering compensation.

Main Results:

• Demonstrated successful depth and intensity measurements in artificial fog, irrespective of fog characteristics.
• Validated the algorithm's effectiveness in real-world foggy conditions through an outdoor experiment.
• Showcased the robustness of the proposed method against varying fog densities and types.

Conclusions:

• The developed time-of-flight algorithm provides a robust solution for depth and intensity sensing in foggy environments.
• The multi-time-gating approach effectively mitigates fog-induced scattering effects.
• This method enhances the reliability of optical sensing for applications requiring operation in adverse weather.