Scraper conveyor chain pitch measurement based on speckle structured light

A chain pitch measurement method of scraper conveyor based on speckle structured light is proposed to improve security and automation. Two speckle structured light cameras are used to collect point clouds on the chain surface from different angles, and the point clouds are transformed to a common reference coordinate system by rotating and translation matrix with calibration. The chain point cloud is preprocessed by plane model segmentation and radius filtering, the main direction of the point cloud is calculated by point cloud principal component analysis, the key points of measurement are detected by neighbors within radius search of the point cloud, and finally, the chain pitch is solved by Euclidean distance. The actual measurement error of the measurement method proposed in this paper is less than 2%, which can meet the needs of coal mining.