Ground structure method-based stiffener layout topology optimization for horizontal machining center headstock cover plate

Abstract

Structural dynamic performance of a machine tool greatly affects machining precision and productivity. One effective approach in improving the dynamic performance is by applying topology design optimization to the machine tool structure. A method based on the Ground Structure Method (GSM) is established to optimize the layout of stiffener structure. The GSM is employed for the construction of the stiffener. The optimal layout of the stiffeners is obtained by optimizing the thickness of each stiffener and penalizing intermediate thicknesses to ensure a clear layout. A topology optimization method based on maximizing the natural frequency is established to achieve maximum natural frequency design of stiffener plate. Finally, a few examples are presented to demonstrate the efficacy of the proposed method in enhancing the basic frequency of the structure. The method has been effectively utilized in the optimal design of the machine tool headstock cover plate. As a result, the lowest six natural frequencies of the headstock are increased by 17.83 %, 17.88 %, 5.99 %, 5.58 %, 19.52 % and 14,53 %, respectively. The new approach outlined in this paper serves as a valuable reference for optimizing the dynamic characteristics of machine tools.