G2 continuous Bezier cutter path smoothing algorithm based on tolerance zone

Abstract

The invention relates to a G2 continuous Bezier cutter path smoothing algorithm based on a tolerance zone. The algorithm comprises the following steps of identifying a continuous processing area; in the continuous processing area, carrying out local interpolation on discrete command points, and converting a polyline processing path into a G1 continuous quadratic rational Bezier curve; adjusting the weights of the two adjacent quadratic rational Bezier curves and a tangential direction at a connection joint so that a processing path reaches G2 continuity; and reconstructing the quadratic rational Bezier curve which does not satisfy a precision requirement through establishing the tolerance zone. By using the method, real-time performance is good, a generated processing path satisfies G2 continuity and the precision requirement, and processing efficiency can be effectively increased.

Description

technical field [0001] The invention relates to the fitting of parametric spline curves in a numerical control system and the control of fitting precision, and belongs to the technical field of numerical control processing. Background technique [0002] In the NC machining of complex workpieces, the CAM system usually converts the complex graphics generated by the CAD system design into a NC machining path composed of a large number of tiny line segments. If the CNC system directly performs interpolation according to the generated processing path, due to frequent acceleration / deceleration control, it will cause vibration of the machine tool, reducing processing efficiency and processing quality. Some high-end CNC systems such as FANUC and SIEMENS have proposed nano smoothing and compressor technology, the purpose of which is to smooth discrete small line segments to form a smooth spline curve, thereby achieving high-speed and high-precision machining, but these technologies ...

AI Technical Summary

Problems solved by technology

For all the above algorithms, whether it is the interpolation method or the fitting method, it can only ensure that the shortest distance from the discrete instruction point to the spline curve meets the contour error, but it cannot guarantee that the small line segment composed of adjacent discrete instruction points will reach the spline curve. The farthest distance does not exceed the set value

At the same time, because the fitting and global interpolation methods need to perform iterative processing or solve complex nonlinear equations, the amount of calculation will increase with the increase of discrete instruction points, and the real-time performance and locality are poor.

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