Cutter axis vector interpolation method in 5-axis numerical control machining with rotation axis angular velocity smoothness characteristic being taken into consideration

Abstract

The invention provides a cutter axis vector interpolation method in 5-axis numerical control machining with rotation axis angular velocity smoothness characteristic being taken into consideration and belongs to the technical field of 5-axis numerical control machining. The method solves the problem of refining interpolation of cutter axis vector at the place of an ordinary cutter location point according to key cutter location set based on cutting property and cutter feasible space. The method is characterized by, to begin with, calculating the rotation angle of each rotation axis corresponding to the key cutter axis vector under a machine tool coordinate system according to an inverse kinematics transformation equation; providing an approximation calculation formula of angular velocity of each rotation axis at the place of each refining interpolation cutter location point by utilizing a finite difference method; then, establishing a least square optimization objective function with the minimum angular velocity change of each rotation axis being an objective, and giving a solving method to obtain the rotation angle of each rotation axis at the place of the refining interpolation cutter location point; and finally, carrying out forward synthesis to obtain cutter axis vector at the place of the refining interpolation cutter location point. The method enables the angular velocity change of each rotation axis to be minimum and smooth and steady, thereby improving kinematics and dynamics performances of a five-axes numerical control machine tool in the process of machining parts of complex surfaces.

Description

technical field

[0001] The invention relates to a tool axis vector interpolation method considering the smooth characteristics of the angular velocities of each rotating shaft in five-axis numerical control machining, belonging to the technical field of five-axis numerical control machining. Background technique

[0002] Five-axis CNC machining is a landmark processing technology in modern industry, and it occupies a dominant position in the precision and complex surface processing of automobile, aerospace, shipbuilding, mold and other industries. The introduction of two rotational degrees of freedom in a five-axis CNC machine tool not only improves the processing flexibility, but also increases the difficulty of tool attitude control. For any tool contact, its corresponding tool axis vector must exist in the feasible processing space of the point to avoid possible local or global machining interference during the machining process, but in fact the tool axis vector at the to...

Images