Command point shaping, compressing and interpolating method suitable for numerical control device

Abstract

The invention relates to a command point shaping, compressing and interpolating method suitable for a numerical control device. The method comprises the following steps of: inserting an arc which has a distance with the middle point of a tolerance set by the numerical control device and is tangential with segments of adjacent command points to the middle point of every three adjacent command points when a numerical control processing procedure judges that any three adjacent command points on a processed curve surface meet a continuous processing condition, wherein the tangential points are used as interpolation points; trimming the interpolation points to reduce calculation errors and rounding errors in the process of reckoning the interpolation points; selecting a characteristic interpolation point through judging the bending directions of processing paths of all the interpolation points; fitting by using a continuous polynomial spline curve with a second derivative to generate a smooth curve; approximately calculating the interpolation points of a current interpolation period and sending the positions of the interpolation points to a servo system of the numerical control device;and driving a servo motor to move. The invention furthest improves the processing efficiency and reduces the influences of the calculation errors and the rounding errors on the processing precision and the processed surface smoothness.

Description

technical field [0001] The invention relates to a numerical control processing technology of complex profiles, in particular to a command point shaping compression interpolation method suitable for a numerical control device. Background technique [0002] Complex profiles are widely used in the design of mold cavities, automotive covers, and aerospace components. However, the high-speed, high-precision and high-quality machining of complex profiles has always been a difficult research point. In NC machining, in order to be able to mill a complete complex surface and detect collisions in real time, the CAM (computeraided manufacture) system usually uses a large number of tiny planes to approximate the complex surface designed by the CAD (computer aided design) system, such as figure 1 As shown, a series of tool paths are used to cover these polyhedrons within a specific tolerance range, and finally a NC machining program consisting of a large number of instruction points is g...

AI Technical Summary

Problems solved by technology

[0004] Aiming at the fact that the existing technology cannot meet the high-speed and high-precision processing requirements of complex profiles, the technical problem to be solved by the present invention is to provide a command point shaping compression interpolation method suitable for numerical control devices with high processing efficiency and high processing accuracy

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