Max-fit biarc fitting to STL models for rapid prototyping processes

ABSTRACT

This paper presents a method of Max-Fit biarc curve fitting technique to improve the accuracy of STL files and to reduce the file size for rapid prototyping. STL file has been widely accepted as a de facto standard file format for the rapid prototyping industry. However, STL format is an approximated representation of a true solid/surface model, and a huge amount of STL data is needed to provide sufficient accuracy for rapid prototyping. This paper presents a Max-Fit biarc curve fitting technique to reconstruct STL slicing data for rapid prototyping. The Max-Fit algorithm progresses through the STL slicing intersection points to find the most efficient biarc curve fitting, while improving the accuracy. Our results show the proposed biarc curve-fitting technique can significantly improve the accuracy of poorly generated STL files by smoothing the intersection points for rapid prototyping. Therefore less strict requirements (i.e. loose triangle tolerances) can be used while genarating the STL files.

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INDEX TERMS

Primary Classification:
  I. Computing Methodologies
  I.3 COMPUTER GRAPHICS
      I.3.5 Computational Geometry and Object Modeling
          Subjects: Curve, surface, solid, and object representations

Additional Classification:
  D. Software
  D.2 SOFTWARE ENGINEERING
      D.2.1 Requirements/Specifications
          Subjects: Elicitation methods (e.g., rapid prototyping, interviews, JAD)

  J. Computer Applications

General Terms:
Algorithms, Design, Measurement, Performance, Theory

Keywords:
CAD/CAM, STL files, biarc curve-fitting, biarc splines, rapid prototyping