Program segment smooth compression processing method suitable for numerical control device

Abstract

The invention relates to a program segment smooth compression processing method suitable for a numerical control device, comprising the following steps: (1) analysis of a processing path, i.e. removing irregular programming points in a numerical control program by filtration, and deducing parts required to conduct smoothness in shape; (2) parameterization of the programming points, i.e. carrying out parameterization on each programming point by means of distances among the programming points; (3) selection of characteristic programming points, i.e. dividing the programming points into the characteristic programming points and non-characteristic programming points by means of processing shape and bending direction at the programming points; (4) calculation of tangent vector at the characteristic programming points, i.e. calculating the tangent vector at the characteristic programming points by constructing an interpolation curve; (5) compression of program segments, i.e. compressing the program segments between the adjacent programming points into a segment of a spline curve; and (6) control of mismachining tolerance, i.e. ensuring the compressed spline curve to meet requirements of machining accuracy by adjusting the shape of the curve segment. The method in the invention can prevent irregularity of a workpiece surface from being caused by line interpolation at transition of the programming segment and has the advantages of high machining accuracy and high efficiency.

Description

Program segment smoothing and compression processing method suitable for numerical control device technical field 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 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, the CAM (computer-aided manufacturing) system usually uses a series of tiny broken lines to specify the processed curves and curved surfaces, and generates a NC machining program consisting of a large number of tiny program segments (straight line segments) , and processed by the numerical control device. When the NC machining program specifies a free curve in a manner simil...

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

Images