A non-orthogonal interpolation algorithm for NC machine tools

In numerically controlled systems, the interpolation function is normally implemented with orthogonal-type algorithms, in which each step of the tool is along a single coordinate axis. These algorithms are easier to conceive and realize.Non-orthogonal interpolation, however, offers certain advantages such as improved curve smoothness and increased feedrates. The algorithm presented in this paper makes possible an extension of the feedrate range of the machine by approximately 28% without any other change in the control. The algorithm is applicable to plane curves, defined implicity by an equation of the form $\text{? (x,y) = 0}$.