Drone-based displacement measurement of infrastructures utilizing phase information

Area of Science:

• Civil Engineering
• Geotechnical Engineering
• Robotics

Background:

• Aging infrastructure requires regular safety assessments.
• Traditional inspection methods can be time-consuming, costly, and hazardous.
• Drone technology offers a safer and more efficient alternative for infrastructure monitoring.

Purpose of the Study:

• To develop a high-precision drone-based framework for measuring structural displacements in bridges.
• To achieve sub-millimeter accuracy in displacement measurements for on-site inspections.
• To enhance the safety and efficiency of bridge inspection processes.

Main Methods:

• Integration of phase-based sampling moiré technique with four degrees-of-freedom geometric modeling.
• Strategic placement of reference markers on bridge girders for displacement measurement.
• Utilizing drone-mounted cameras for data acquisition and analysis.
• Developing algorithms to differentiate structural displacement from camera motion.

Main Results:

• Achieved sub-millimeter accuracy in displacement measurements, reaching 1/100th of a pixel precision.
• Demonstrated the reliability and efficiency of the drone-based system through real-world validations.
• Successfully delineated bridge displacements from camera motion-induced displacements.

Conclusions:

• The developed drone-based framework provides a practical and accurate tool for bridge displacement measurement.
• This technology enhances safety and efficiency in assessing aging infrastructure.
• The methodology lays the groundwork for future autonomous infrastructure inspection systems.