基于并行工程思想的参数和公差经济性设计,以成本为优化目标来确定最优的设计参数和公差范围.就并行参数和公差设计通过双响应曲面均值和方差模型实现其稳健性,本文提出了包含噪声因子的响应曲面建模策略,应用这一模型将参数和公差同时优化.该参数和公差经济性设计优化模型以质量损失和制造成本之和为目标函数,以过程方差置信域为约束.实例结果表明,在双响应曲面方法中,对均值设置偏倚量比其刚性约束具有较大的成本优势,在不降低稳健性的前提下引入偏倚可以降低成本.面向噪声因子的设计策略其成本低于基于双响应的有偏倚的设计,说明考虑噪声因子的设计是最有效的.
Economic parameter and tolerance design is based on the concurrent engineering philosophy with cost objective function to get the optimized parameter value and tolerance ranges. It has been recognized that the mean and variance models of Dual Response Surface Method (DRSM) is an effective method for concur- rent parameter and tolerance design in realizing robustness. Based on this, a strategy of constructing response surface model including noise factors was put forward which can concurrently optimize parameters and toler- ances. The optimized model for economic parameter and tolerance design is subject to confidence region of process variance of Response Model (RM) and its optimized function is the sum of quality loss and tolerance cost. A numeric example is used to illustrate its effectiveness. The results show that the design taking into con- sideration noise factors is the most effective model. In DRSM, there is more cost reduction effect when a bias is set to the mean model compared with the rigid restriction (mean equals target). Relaxing the mean con- straint (setting bias) brings about cost reduction without loss of robustness. The design strategy taking into consideration noise factors achieves more benefit ( cost reduction) than the DRSM with given bias and with the same robustness.