Measurement analysis and rectification of positioning errors associated with three-axis machining center

摘要

The complex structures of the three-axis machine tools produce an inaccuracy at the tool tip which is caused by kinematics parameter deviation resulting mainly from manufacturing error and assembly error. Here all linear axes are theoretically perendicular (dot product, cos 90°= 0) to each other and directed along the X, Y; Z coordinate but in working machines the axes are nearly perpendicular(cos 89.9° ≠ 0) because of the reasons mentioned above. This kind of error can be taken into consideration only by the precise description of the actual kinematics of the machine tool. This paper attempts to develop kinematics for the three-axis machine with one rotational tool axis, along with its practical verification by error measurement. Here, an algorithm for error compensation along with block diagram for error compensation is also suggested.