Computer supported force analysis and layer imagine for masked rapid prototyping system

An innovative rapid prototyping (RP) system using direct mask photo curing (DMPC) is proposed in this paper. The underlying principle of the RP system is to fabricate a three-dimensional part layer by layer. The design concept of the DMPC RP system is to use a dynamical photo mask for the layer profile. The image of the dynamic mask, generated by a thin film transistor liquid crystal display (TFT LCD) panel, is calculated from the slicing data of the CAD model. In the DMPC system, the photopolymer is exposed and shielded by the LCD mask, and the light source to cure the photopolymer is from the bottom of the transparent resin container. A residual force is formed between the layer of the cured photo-polymer and the silicon film on the container. This residual force is measured using a load-cell and its theoretical model is further developed and simulated using the finite element method. Hence, the force measurement, force simulation, layer imagine calculation, LCD control, position control and process parameters are supported by a host computer. As a result, good quality parts with low cost can be built by this proposed DMPC RP system.