3D Concrete Printing with Variable-Width Filament (2021-09)¶

Traditional mold-based concrete construction methods are inefficient, poor quality, and labor-intensive. Concrete 3D printing technology is expected to replace traditional methods as an emerging intelligent construction method due to its flexible, automatic, fast, and mold-free features. Concrete 3D printing is a method by extruding and selectively laminating construction materials onto a specific path, relying on fine-grained control ofthe printing material and the printing device. However, the maximum printing resolution is limited by the width ofthe toolpath. Filament width and printing resolution are two main factors that need to balance. In this paper, a variable width printing method is proposed using the active nozzle speed control method. The width ofthe print path can be adjusted according to the model details. A width control algorithm is proposed. The general workflow ofvariable width printing, including model preparation, toolpath planning, robotic fabrication, is also introduced, and a concrete bench is printed for experimental validation. The result shows great application potential for surface decoration and structural reinforcement. The efficiency, feasibility, and problems encountered in printing are analyzed and summarized.