Tool path generation of turning optical freeform surfaces using arbitrary rake angle tools.

Slow tool servo diamond turning has widespread application in fabricating freeform optics. Previous studies are focused on the methods of the tool path generation and verification of zero-rake-angle tools. However, these methods are unsuitable for non-zero-rake tools that are used for machining hard-and-brittle materials. This paper presents a universal location-point-drive tool path generation method, which caters to arbitrary rake angle tools and the steady X movement feature, and the corresponding universal tool interference check method. Systematic analysis and ultra-precision machining experiments confirmed the feasibility of our methods and present better surface quality and form accuracy compared to the traditional method.