Elliptic arc interpolation method

Abstract

The invention relates to an elliptic arc interpolation method, which comprises the following steps of: 1, expressing an elliptic track where an elliptic arc is located in a parameter form of a standard elliptic equation; 2, calculating a stepping angle delta theta between a current interpolation point Pi (xi, yi) and a next interpolation point Pi+1 (xi+1, yi+1); 3, calculating a coordinate of thenext interpolation point Pi+1 (xi+1, yi+1) according to the coordinate of the current interpolation point Pi (xi, yi); and 4, making interpolation reach an end point of the elliptic arc if the current interpolation point Pi (xi, yi) does not exceed the end point of the elliptic arc and the next interpolation point Pi+1 (xi+1, yi+1) just reaches or exceeds the end point of the elliptic arc, and finishing interpolation process; otherwise, making the interpolation not reach the end point of the elliptic arc, carrying out the interpolation by using the Pi+1 (xi+1, yi+1) as a new current interpolation point, and then returning to the step 2. The elliptic arc interpolation method is applied to the interpolation of anticlockwise and clockwise elliptic arcs which have any start points and any endpoints and the whole ellipse, so that calculation of the interpolation points is simple and fast, the accuracy of the track is high, and discrimination of the end point is fast and correct.

Description

technical field [0001] The invention relates to the technical field of numerical control, in particular to an ellipse arc interpolation method. Background technique [0002] In the process of laser trajectory processing, the machine tool driven by the servo motor cannot strictly follow the trajectory curve required to be processed, and can only approach the trajectory curve to be processed with a broken line trajectory. The numerical control device uses an interpolation algorithm to calculate the position of the interpolation point, and generates the interpolation point through the interpolation calculation, thereby decomposing the continuous trajectory curve into discrete points. The discrete interpolation points are sent to the position control module of the numerical control system to control the machine tool to generate motion trajectories. [0003] In CNC equipment such as CNC laser marking machines, CNC laser cutting machines, and CNC end face grinders, it is often ne...

AI Technical Summary

Problems solved by technology

However, the existing elliptic arc interpolation algorithm is either complex in calculation and low in efficiency, which makes it difficult for the numerical control system to achieve real-time processing, or the use of approximate calculations leads to low precision of interpolation point coordinates, and the discrimination algorithm of the end point is also complex and discriminant. The problem of low accuracy

Images