基于小位移旋量公差建模和蒙特卡洛模拟的装配体公差优化设计方法

提出一种基于小位移旋量(SDT)公差建模和蒙特卡洛模拟的装配体公差优化设计方法,通过分析装配精度链、装配结合面和结合面公差3个对装配精度具有重要影响的核心要素之间的关系,利用SDT理论和蒙特卡洛模拟法建立公差模型,再利用齐次变换理论建立结合面误差模型和装配精度模型,进而推导出装配体装配精度与结合面公差相关的映射模型;结合公差制造成本、装配精度可靠度原则,建立装配体装配精度的公差优化模型,并以顶尖装配体为例完成公差优化分析。研究发现:在满足装配精度可靠度的前提下,可使顶尖装配体加工成本降低9.02%,而装配精度可靠度提高至97.81%,验证了所提方法的有效性。

An Assembly Tolerance Optimization Design Method Based on SDT Tolerance Modeling and Monte Carlo Simulation

An assembly tolerance optimization design method based on SDT tolerance modeling and Monte Carlo simulation was proposed.Through analyzing the relationship among the three core elements,namely the assembly accuracy chain,assembly joint surface and joint surface tolerance,the tolerance model was established using SDT theory and Monte Carlo simulation method,then homogeneous transformation theory was used to establish the joint surface error model and assembly accuracy model,and then the mapping between assembly accuracy and joint surface tolerance was deduced.Combining tolerance manufacturing cost,assembly accuracy reliability principles,a tolerance optimization model for assembly accuracy was established.Finally,tolerance optimization analysis was carried out with the top assembly as an example.It is found that,under the premise of meeting the reliability of assembly accuracy,the processing cost of the top assembly can be reduced by 9.02%,and the reliability of assembly accuracy can be increased to 97.81%,which verifies the effectiveness of the proposed method.