考虑使用强度的楔式动力卡盘可装配性分析

提高卡盘的强度,是提高卡盘的静态夹紧力,进而提高卡盘极限转速的必要手段。为了改善零部件制造误差引起的卡盘主要相对运动表面之间的接触状态,避免出现应力集中,进而保证卡盘使用时的强度,对批量制造的卡盘的可装配性进行了研究。将批量制造装配出的每台卡盘都能达到最佳强度状态作为可装配性条件,建立了可装配性条件的等效数学模型,采用蒙特卡洛法求解得到了卡盘关键零部件制造公差应该满足的约束关系。

复杂产品装配性分析方法探讨

概要介绍装配性分析(DFA)的含义和国外应用于复杂产品结构工艺性评定的基本情况。根据复杂产品特点,将装配性分析分为定性评审、宏观指标评估、结构化定量评估三种情况,分别论述了其要点、主要指标。在结构化评估方法中重点介绍了Boothroyd方法。最后,分析了复杂产品的装配特点,指出在研究应用定量评估方法时应注意“四结合”的原则,并以简图形式描述了并行工程环境下复杂产品开发过程。

基于精度模型的虚拟装配技术研究

产品设计过程中对其进行虚拟装配和分析,可以尽早发现实际装配过程中可能存在的问题,在产品整个装配过程中零部件的公差对能否装配成功具有重要的影响。研究了基于装配精度模型的虚拟装配技术,主要包括装配工艺规划、产品可装配性分析与评价、公差分析与综合、装配仿真等,基于装配中公差的传播,详细分析了产品可装配性及评价方法,并将其应用到系统中实现。

基于组件应用框架的装配工艺规划系统开发

介绍了组件应用框架的开发过程、编译方法和程序结构,基于组件应用框架开发了与CATIA集成的装配工艺规划系统,本系统已用于某型飞机机翼装配工艺规划。

虚拟环境下人工拆卸的实现

从产品装配性分析的角度出发 ,提出了在虚拟环境下进行人工装配 (拆卸 )的方法 .借助数据手套、头盔装置等输入输出设备 ,在虚拟环境下操作者可以对装配体中的零件进行抓取、移动 ,并记录装配体拆卸顺序与各零件的拆卸路径 ,从而为产品的装配分析提供依据 .讨论了实现虚拟人工拆卸的若干关键技术 ,并用示例说明了该方法的有效性 .

样车试制与预批量生产的有效结合研究

为提高样车预批量阶段产品的成熟度,减少更改、降低成本、缩短项目周期,对样车试制与预批量生产的特点进行了分析,对试制工艺与批量工艺进行了对比,并针对预批量生产面临的重点问题进行了研究,提出了将样车试制与预批量生产有效结合的方法,通过虚拟装配、可装配性分析等提前对产品设计、生产工艺进行验证,保障预批量生产的顺利进行。

Mapping relationship analysis of welding assembly properties for thin-walled parts with finite element and machine learning algorithm

The finite element(FE)-based simulation of welding characteristics was carried out to explore the relationship among welding assembly properties for the parallel T-shaped thin-walled parts of an antenna structure.The effects of welding direction,clamping,fixture release time,fixed constraints,and welding sequences on these properties were analyzed,and the mapping relationship among welding characteristics was thoroughly examined.Different machine learning algorithms,including the generalized regression neural network(GRNN),wavelet neural network(WNN),and fuzzy neural network(FNN),are used to predict the multiple welding properties of thin-walled parts to mirror their variation trend and verify the correctness of the mapping relationship.Compared with those from GRNN and WNN,the maximum mean relative errors for the predicted values of deformation,temperature,and residual stress with FNN were less than 4.8%,1.4%,and 4.4%,respectively.These results indicate that FNN generated the best predicted welding characteristics.Analysis under various welding conditions also shows a mapping relationship among welding deformation,temperature,and residual stress over a period of time.This finding further provides a paramount basis for the control of welding assembly errors of an antenna structure in the future.

Analysis and optimization of assembly variations for non-rigid parts

Traditional variation analysis methods are not applicable to non-rigid assemblies due to possible part deformation during the assembly process. This paper presents the use of finite element methods to simulate assembly deformation. The relationship between the parts’ variation and the variation of the key points in final assembly for quality control is set up by calculating the spring back deformation after assembly. Moreover, the optimization method for non-rigid assembly variations based on finite element analysis is presented. The optimal objective is to reduce the manufacturing cost. The approach is implemented by using ANSYS and MATLAB. The test example shows that the proposed method is effective and applicable.

农业机械虚拟现实模拟试验台的设计

在现代农业虚拟现实实验室里对农业机械进行的设计、装配和试验，其主要特点是，在没有实际制造出物理样机以前，就可以对产品进行过程分析、性能分析、可装配性分析、工艺规划和优化设计等。由于不需要制造出物理样机，而采用由虚拟现实技术设计出来的虚拟样机代替，产品的反复设计、制造和测试也是在虚拟样机上进行。出现问题时，只需在虚拟样机上改进，大大缩短了生产周期，节约成本。