The successful control and operation of the stereolithograpy (SL) process d
epends on many parameters. These can be categorized systematically into: ha
rdware, i.e., the construction and mode of operation of the machine; the co
ntrolling software such as the hatching pattern, error compensation and par
t orientation; and the material properties of the photo-polymer. The improv
ement of the current SL process is approached from both the software and ha
rdware viewpoints. In the software study, the following issues are consider
ed: (a) a correction table for compensating on the positioning accuracy; (b
) STL slicing software with an editing and automatic error-correction funct
ion; (c) a direct slicing algorithm to be used on commercial CAD software;
(d) the optimal part orientation software and (e) a variable slicing algori
thm. For hardware and material studies, a novel process using a mixture of
Aerosil silica powder and photo-polymer was developed. The resulting mixtur
e not only reduces the requirement for support structures fur the model hen
ce shortening the model-building time, but also improves the properties of
the model, such as tensile strength, shrinkage rate, etc. (C) 2001 Elsevier
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