Volume-based spatial partitioning and process planning of freeform multi-material objects for rapidly-reconfigurable molding process

In this research, geometric algorithms for representation and fabrication of three-dimensional (3D) freeform multi-material objects using a rapidly-reconfigurable molding process have been presented. The rapidly-reconfigurable molding system consists of many discrete arrays of pins each forming the mold-face of a mold block. The array of pins in different mold faces approximates the boundaries of different type of materials in a multi-material object. A new material representation scheme is proposed for freeform multi-material objects in which material information is added to the solid model based on boundaries of the homogeneous regions in the multi-material object. The geometric algorithms detailed in this paper analyze the given multi-material object and decomposes it based on the material regions and manufacturability of the regions using silhouette-edge based method. The decomposed multi-material object will consist of undercut and non-undercut features or a combination of both. The algorithm detects undercut regions in the multi-material object and adds support material. The processing sequence is then determined to fabricate the decomposed multi-material object using the reconfigurable molding process. The sequence of processing the decomposed multi-material object is determined by identifying the type of surfaces that exists in the decomposed multi-material object. Computer implementation and illustrative examples are also presented to demonstrate the developed methodologies. (Abstract shortened by UMI.)...