Effect of servo and geometric errors of tilting-rotary tables on volumetric errors in five-axis machine tools

• Volumetric circles are developed to evaluate servo errors of a tilting-rotary table.
• An integration concept of servo and geometric errors is presented in this paper.
• A test part is developed to validate the evaluation method presented in this paper.

The tilting-rotary table becomes a standard accessory for five-axis machine tools. An approach for volumetric errors evaluation taking into account servo and geometric errors of the tilting-rotary table is proposed in this paper. A simple machining model of volumetric circles is used to evaluate volumetric errors due to servo errors of the tilting-rotary table. A kinematic error model is used to predict the volumetric errors resulting from geometric errors associated with the tilting-rotary table. Then effects of the two error sources are added to predict the total volumetric errors. A test part obtained by improving the cone frustum specified in NAS979 is presented to validate this method. Cases studies with cutting experiments are carried out on a commercial five-axis machine tool. The results show that the proposed model is effective to evaluate the effect of servo and geometric errors of the tilting-rotary table on volumetric errors in the five-axis machine tool.