Shimizu Corporation has developed a spray-based 3D concrete printing system designed to construct large, curved reinforced components. The system combines a nine-degree-of-freedom gantry robot with a material spray simulator that can verify sprayed-material behavior before actual printing. The material spray simulator was developed in collaboration with Carnegie Mellon University’s Computational Engineering and Robotics Lab. Credit: Shimizu The system addresses limitations of conventional material extrusion 3D printing methods, which deposit cementitious materials layer by layer but struggle to integrate rebars into printed layers. Spray-based printing allows for better integration of reinforced structural components by spraying cementitious materials to form structures. However, this method has historically faced challenges with printer motion control and fabrication accuracy. The new system uses a material spray simulator to determine optimal printing parameters, including nozzle paths, spray distance, angle, speed, and material discharge volume. The gantry robot features a seven-degree-of-freedom arm suspended from a two-axis XY motion… read more