The rail wear measurement has its importance on the maintenance of railways, and data acquisition and processing are crucial tasks for rail wear measurement. Rail wear directly influences wheel-rail contact and life of rail tracks, so accurate and effective measurement of rail wear is a continuous demand. In this paper, a structured light data acquisition system is developed, and a data processing method for the alignment of point clouds from structured light scanning and CAD model of the rail is proposed for rail wear measurement. For the alignment of the structured light data and CAD model, random points sampling from...