3D Geometric Measurements of 3D Printed Concrete via Structured Light Machine Vision

Automated inspection and quality control of the robotic 3D printing process remains a key challenge for the broader adoption of this innovative construction method. To address this, a novel methodology for in-process geometrical measurement of 3D printed layers using laser light machine vision is proposed. This system utilizes a vision algorithm to process data from a 2D camera, enhanced by a structured laser light (SLL) pattern, to measure both the width and height of the extrudates. A systematic validation program, including single-layer and multi-layer deformed specimens, was conducted to evaluate the proposed methodology. The results demonstrate that the designed SLL vision system delivers continuous geometrical measurements with a maximum error of less than 1 mm. The SLL algorithm’s processing time of 0.25 s, combined with its high measurement accuracy, indicates its great potential for real-time geometrical measurements during robotic 3D printing.