A control algorithm for a vertical five-axis turning centre

It is very useful to accomplish turning and five-axis milling, drilling and boring in only one setup, which is possible on five-axis turning centres. In this paper, we present a control algorithm for this machine with two translational and three rotational axes. The turning centre has a two rotary axis head with axes that do not intersect. This increases the possibility of machining and allows for certain types of machining without the machine taking the singular positions. The high angular speed of the table required for turning causes heating of the table-bearing support and base thermal deflection. If milling or drilling is done immediately after turning, the motion of the machine axis should be corrected to eliminate the error in machining that arises because of the deflection, a correction that has been done in this paper. The solution for the forward and inverse kinematics for this type of machine allows for programming the machine motion as if the machining were performed on a five-axis gantry milling machine. This has essentially facilitated machine programming.

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