关键词: 机床, 结构, 形状, 最佳设计

Abstract: This paper presents some new concepts on efficient combination of geometrical optimization and size optimization of machine tool structures. A special element- "quasi-element"---has been introduced for the optimization of structural geometry of a three dimensional plate system with special meshings. In the process of treating of variables, the design space may be differentiated into size subspace and geometrical subspace to suit, different objective and constraint functions such that the variables within a subspace can be both reduced and unified. Quadratic polynomial fitting method has been used to reduce the amount of computation for the structural approximate re-analysis and has been proved to be both accurate and effective. An illustrative example of a certain lathe bed, showing the :geometrical optimization minimum weight, has been given with a result that a weight reduction of 8.9% is obtained for size optimization alone, but 25.4% for size and geometrical optimization both.

Key words: 机床, 结构, 形状, 最佳设计