Feedrate scheduling for free-form surface using an NC verification model

This paper describes feedrate scheduling for a free-form surface using an NC verification model that can describe the actual cutting motions. This is important from the viewpoint of verification of the free-form surface and feedrate scheduling in the same simulator. In this paper, feedrate scheduling is conducted using the chip volume per tooth and per NC block using an NC verification model in order to obtain a constant chip load. A strategy for generating new NC commands at a set number of rotations between two existing NC blocks with a constant chip volume per tooth is proposed. The travel length of acceleration/deceleration is compensated in generating a new NC command in an NC block. Chip loads for feedrate scheduling are rapidly obtained in all tool paths considering surface curvature, feedrate, and cusp height formed by the previous tool path. Experiments validated that the presented feedrate scheduling obtained a constant chip load in all tool paths by inserting new NC commands in the existing NC file.