基于数论网格法的三维单工序装配成功率计算方法

Evaluation Method of Assembly Yield in Three-dimension Single-station Assembly Processes Based on Number-Theoretical Net

提出了一种基于数论网格法的三维单工序装配成功率计算方法。首先,基于三维单工序装配偏差模型,考虑销-孔/槽副任意布局下夹具定位偏差对装配偏差的影响,建立销-孔/槽副任意布局的三维单工序装配偏差模型。然后,阐述了数论网格采样的基本原理,运用数论网格法对零件偏差采样,基于所建立的销-孔/槽副任意布局下的三维单工序装配偏差模型,建立三维单工序装配成功率模型。最后,针对三维薄板零件装配实例,采用所建立的装配成功率模型计算其装配成功率,并采用3DCS对所建立的装配成功率模型进行仿真验证,仿真结果与理论模型计算结果相比,装配成功率相对误差为0.21%,表明了该方法的有效性。

Evaluation method of assembly yield in three-dimension single-station assembly processes is presented based on Number-Theoretical Net（NT-net）. Firstly, based on the analysis of fixture location deviation affect assembly deviation under pin-hole/slot vice arbitrary placement, the three dimensional single-station assembly deviation model under pin-hole/slot vice arbitrary placement is developed. Then, the principle of NT-net method is introduced, taking parts variations which are sampled using NT-net method for input vectors, based on the three dimensional single-station assembly deviation model under pin-hole/slot vice arbitrary placement, the assembly yield model in three-dimension single-station assembly processes is established. Finally, a real case of sheet metal assembly is given as an example to calculate the assembly yield in three-dimension single-station assembly processes and the 3DCS is used to simulate and verify the presented model. Comparing the simulated result with the result calculated by the theoretical model, the relative error is 0.21% which means the effectiveness of the presented method.