Smoothing methods

Introduction

A programmed contour smoothed within specific tolerances to allow it to move as quickly and uniformly as possible even over corners without stopping.

In general, it is advisable to program the smoothing methods using as many decimal places as possible. This increases the accuracy of the internal calculations and thus the quality of the smoothing methods.

There are various processes available for contouring:

Contour mode: Polynomial contouring is ideal for simple contours with few long linear and circular blocks. This is selected by using G61/G261 and deselected with G260, for example. This method is described in section G functions [PROG].

It is preferable to use the two HSC methods Surface and B spline when there are several short linear blocks:

Surface: The highly rugged SURFACE method is particularly suited to free-form surface machining. It achieves the best results in the event of disruptions in the programmed contour and blocks which have very different lengths. By contrast, this places greater requirements on the hardware.

B spline method: The B spline method can also be used to trim a contour or for very regularly spaced control points. It requires less high-performance hardware.

The two methods Surface or B spline should be supplemented by the options CIR_MODE and the channel parameter P-CHAN-00239 in order to additionally smooth circular blocks in HSC programs. If NC programs contain many short blocks, it is advisable to use the HSC profile generator #SLOPE[TYPE=HSC].

Filter: Besides smoothing a programmed contour, it may be useful to filter axis command values symmetrically. The corresponding functions are described in the function descriptions [FCT-C37] FIR filter.

Apart from these recommended standard methods, there are a number of other methods such as interpolation with the Akima spline [PROG], the direct programming of B spline control points [PROG] and older HSC functions with OP1 and OP2 [PROG].