Software Tools for Solid Freeform Fabrication

Abstract

A structured design methodology played a key role in the VLSI (Very Large Scale Integration) revolution. In this methodology, the design is abstracted at different levels (viz. system, function, logic, circuit, and layout) taking into account concerns relevant to a particular level of abstraction. This allows development of CAD tools that can describe, synthesize, and simulate the design at high levels of abstraction independent of the details of the lower levels. In recent years, many researchers have observed that the lessons learned from the "VLSI experience" could be profitably applied to new classes of manufacturing processes called SFF (Solid Freeform Fabrication). The advent of SFF has opened up new possibilities for rapid prototyping and agile distributed manufacturing. This thesis is concerned with developing tools capable of aiding the rapid prototyping process. We have developed an algorithm for the slicing of 3D polyhedral solid objects into layers capable of being passed to process planners for model fabrication. In support of the slicer algorithm, two new process planner algorithms have also been designed and implemented, one for LAD RP (Laser Aided Direct Rapid Prototyping), and another for SLS (Selective Laser Sintering). These two new algorithms are able to accept model layers from the slicer, and convert the geometric information into command languages that can be understood by the laser controllers in each of the fabrication processes. The software tools have been linked to the fabrication system at the LAMMP lab at CREOL, and parts have been produced using the tools.