Tool orientation sequence smoothing method based on the discrete domain of feasible orientations

Abstract

End milling is widely applied in high-speed machining (HSM), and the tool orientation sequence not only influences on the tool interference but also on the machining quality. The abrupt change of tool orientation may cause over-cut which could scrap the workpiece. There has been a relatively vast class of tool path optimizing method that could decrease the inclination angle along the machining track, but the irregularity point of the machine movement process could not be avoided. This paper describes a tool orientation smoothing method based on the discrete domain of feasible orientations. Firstly, the mapping relation of tool inclination and rotation angles of CNC machine tool rotary axes is formed. Secondly, the cost function and the boundary conditions are formed based on the machine tool distribution. Thirdly, the discrete domain of feasible orientation (DDFO) model is formed by sampling the feasible orientations at each point along the tool path. Finally, the Dijkastra method is applied to find the shortest path in DDFO model and the initial tool orientation sequence is smoothened. And the simulation experiments are implemented to prove the validity of the method proposed.