Development of a sheet-based material handling system for layered manufacturing

Computer-aided manufacturing of laminated engineering materials (CAM-LEM), developed at Case Western Reserve University, is a layered-manufacturing approach utilizing automated stacking of parts laser-cut from sheet materials. This paper presents the design of a material-handling system and its integration with a modular laser-cutting system, completing the most recent version of CAM-LEM. Our material-handling system is required to: transfer individual sheets from at least three material stacks to the cutting table of the laser-cutting system; extract single-layer, laser-cut parts from the cutting table; and stack the parts onto a vertical-stack assembly, resulting in fabrication of a 3D object. Design philosophy, details, and stacking performance measurements of the constructed system are presented. It is shown that the resulting system is capable of assembling objects within a 150 mm cube with an assembly precision of approximately 0.050 mm. Further, the assembly operations are relatively fast, so that part build rates are limited primarily by the laser cutter.