Review of in-motion extended-range 3D optical measurement for industrial applications

Acquiring three-dimensional (3D) shape information plays a vital role in the industrial field, with optical methods being widely adopted. For industrial surfaces that exhibit continuous extension, such as trains, tracks, tunnels, and production lines, performing in-motion extended-range 3D shape measurement has become an important requirement due to its high efficiency, excellent continuity, and strong adaptability to relevant scenes. This paper overviews the state-of-the-art in-motion extended-range 3D optical metrology for industrial applications. It outlines the measurement procedure and identifies key challenges. A comprehensive survey of optical methods for 3D point cloud generation and extension is presented, along with techniques for controlling micro and macro accuracy during continuous motion and strategies for ensuring data completeness in a single dynamic scan. The paper concludes with insights into future development directions.