面向变量不确定性的汽车结构可靠性设计研究

Research on Reliability Design of Automobile Structure Facing Variable Uncertainty

针对汽车结构轻量化设计,提出了计入不确定制造精度的汽车结构可靠性设计方法。首先将主要设计变量视为区间变量,其他设计参数被视为概率值,在此基础上采用区间模型的变换方法和概率模型的解耦策略,建立汽车结构制造精度不确定的可靠性设计方法。通过经典悬臂梁和停车机器人机架的轻量化优实例分析,得到了不同可靠性要求下的最优解和最大允许偏差范围,验证了本研究方法的有效性。优化设计结果表明,在可接受的制造条件下,可以得到最优变量和相应的最大允许偏差范围。通过适当增加设计变量的偏差范围,可以降低对制造精度的要求,从而降低制造成本。

Aiming at the lightweight design of automobile structure,a reliability design method of Automobile Structure Consid-ering Uncertain manufacturing accuracy is proposed.Firstly,the main design variables are regarded as interval variables and other design parameters are regarded as probability values.On this basis,the reliability design method with uncertain manufac-turing accuracy of automobile structure is established by using the transformation method of interval model and the decoupling strategy of probability model.Through the analysis of lightweight optimization examples of classical cantilever beam and parking robot frame,the optimal solution and maximum allowable deviation range under different reliability requirements are obtained,which verifies the effectiveness of this research method.The optimal design results show that the optimal variables and the corre-sponding maximum allowable deviation range can be obtained under acceptable manufacturing conditions.By properly increas-ing the deviation range of design variables,the requirements for manufacturing accuracy can be reduced,so as to reduce the manufacturing cost.