Program segment smoothing and compression processing method suitable for numerical control device

Abstract

The invention relates to a method for smoothing and compressing program segments suitable for a numerical control device, comprising the following steps: 1) Analyzing the processing path: filtering out irregular programming points in the numerical control program, and inferring the part requiring shape smoothness; 2) programming Point parameterization: parameterize each programming point by the distance between the programming points; 3) Select feature programming points: divide the programming points into feature programming points and non-feature programming points by the bending direction of the processed shape at the programming points ; 4) Calculate the tangent vector at the feature programming point: calculate the tangent vector at the feature programming point by constructing an interpolation curve; 5) Compress the program segment: compress the program segment between the adjacent feature programming points into a section of the spline curve; 6) Control machining error: ensure that the compressed spline curve meets the machining accuracy requirements by adjusting the shape of the curve segment. The method of the invention can avoid uneven workpiece surface caused by linear interpolation at the transition of program segments, and has high machining accuracy and high efficiency.

Description

technical field [0001] The invention relates to a numerical control processing technology, in particular to a program segment smoothing compression processing method suitable for a numerical control device. Background technique [0002] Free curves and curved surfaces are widely used in the design of mold cavities, automobile covers, and aerospace components. However, the NC machining of free curves and curved surfaces has always been a difficult point in research. In the NC machining of free curves and curved surfaces, CAM (computer-aided manufacturing, calculation-aided manufacturing) systems usually use a series of tiny broken lines to specify the processed curves and curved surfaces, and generate NC machining consisting of a large number of tiny program segments (straight line segments) program, and processed by the numerical control device. [0003] When the NC machining program specifies a free curve in a manner similar to a broken line, under certain tolerance condit...

AI Technical Summary

Problems solved by technology

For a shape part composed of a free curve with a small radius of curvature, the length of the program segment is short, and the linear interpolation at the transition of the program segment will cause the acceleration of each motion axis to jump frequently, which will cause the vibration of the machine tool and eventually cause the workpiece The surface is uneven; and for the shape part composed of free curves with a large radius of curvature, the length of the program segment is long, and the linear interpolation at the transition of the program segment will cause the knuckles between adjacent program segments to be very obvious, thus also Can cause unevenness on the machined surface

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