An optimizing tool orientation method for positional 5-axis machining

Positional 5-axis machining is widely applied in high-speed machining the surfaces of automobile panel dies. Its key factor is to set up an appropriate tool orientation. The relationship between tool orientation and tool-axial inclination was analyzed, and the optimization method based on planar fitting was proposed. It consists of three steps: Firstly, the machining surfaces are scattered to points and fitted a plane, and the tool-axis is tilted a angle α that is recommended as the initial tool-axial inclination, in the plane which is defined by the feed direction and the normal direction of the fitted plane; Secondly, the heel angle of each point on machining surfaces are calculated, and the numeral scales of machining points whose inclinations are in a certain range to all are also counted; Finally, it is drawn that if the tool-axial orientation is optimal based on the counted result, otherwise, it is needed to reselect a new or to re-divide the machining areas until a satisfactory result is gotten. In addition, a software tool was developed to optimize tool orientation for positional 5-axis machining, and an application case was introduced to prove the validity of the method.