NC milling error assessment and tool path correction

ABSTRACT

A system of algorithms is presented for material removal simulation, dimensional error assessment and automated correction of five-axis numerically controlled (NC) milling tool paths. The methods are based on a spatial partitioning technique which incorporates incremental proximity calculations between milled and design surfaces. Hence, in addition to real-time animated five-axis milling simulation, milling errors are measured and displayed simultaneously. Using intermediate error assessment results, a reduction of intersection volume algorithm is developed to eliminate gouges on the workpiece via tool path correction. Finally, the view dependency typical of previous spatial partitioning-based NC simulation methods is overcome by a contour display technique which generates parallel planar contours to represent the workpiece, thus enabling dynamic viewing transformations without reconstruction of the entire data structure.

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Index Terms

• Applied computing

  • Operations research

    • Computer-aided manufacturing

• Computing methodologies

  • Computer graphics

    • Image manipulation

    • Rendering

    • Shape modeling

• Theory of computation

  • Randomness, geometry and discrete structures

    • Computational geometry