Patent Number: 6,401,006

Title: Machine controller with primary and secondary interpolation

Abstract: A controller to smoothly change speed of a machining tool to improve machining accuracy and speed of a machine. The controller includes a command analyzing section included in a block structure of software that analyzes a command program and converts it to data appropriate for use in a primary interpolation section. The primary interpolation section performs interpolation calculation in each first sampling period to obtain an interpolation point on a commanded path, and outputs the obtained interpolation point to an intermediate memory. The intermediate memory stores a motion amount for each axis, a feed rate and a block length. An acceleration/deceleration control section performs acceleration/deceleration control based on the data stored in the intermediate memory, and calculates speed in each second sampling period which is shorter than the first sampling period, to output the calculated speed to a secondary interpolation section. The secondary interpolation section defines a smooth curve expressed, for example, by a polynomial based on output from the acceleration/deceleration control section and the data in the intermediate memory, to output an interpolation point on the smooth curve in each second sampling period.

Inventors: Mizuno; Tohru (Tama, JP), Otsuki; Toshiaki (Hino, JP), Sagara; Shouichi (Yamanashi, JP), Saito; Yasuhiro (Yamanashi, JP)

Assignee: Fanuc Ltd.

International Classification: G05B 19/416 (20060101); G05B 19/41 (20060101); G05B 19/4103 (20060101); G05F 019/00 (); G05B 019/41 (); G05B 019/25 ()

Expiration Date: 06/04/2019