Energy saving design of the spindle of CNC lathe by structural optimization

To fundamentally improve the energy efficiency of computer numerical control (CNC) machine tools, it is essential to study the energy saving in the design stage. The spindle system is one of the most important energy consumers of CNC lathe, and the optimization design for spindle is considered an effective energy saving strategy. However, little research has focused on this issue, and most previous optimization design methods aimed at improving the machining performance such as deformation and vibration. Since previous studies paid little attention to energy saving design, we attempt to consider the energy consumption in the spindle design stage. First, the energy consumption function of the spindle is built, and the optimization objectives are selected. The structure parameters that significantly affect the optimization objectives are determined as the design variables. Then, on the basis of the effective fitting method and dimensionality reduction, a comprehensive objective is defined. Finally, the biogeography-based optimization (BBO) algorithm is adopted to optimize the proposed model. The results indicate that the proposed method can reduce the energy consumption and improve the static and dynamic performance. The impact of the design variables on the objectives is discussed, which provides the guidance for the spindle optimization design.