大口径望远镜中间体拓扑优化及形位公差检测

为了满足大口径望远镜中间体高刚度、低惯量的技术需求,开展了中间体的轻量化设计,同时针对传统方法无法检测中间体形位公差的问题,提出基于自准直仪和激光跟踪仪的光学检测方法。根据望远镜整体结构需求,确定中间体尺寸范围,分析力的传递路径,以应变能最小为优化目标,采用变密度法进行拓扑优化分析和结构设计。基于自准直仪测角原理,在中间体轴孔端面吸附平面反射镜,测量两端面的反射角度,实现两侧轴孔端面平行度误差的测量,基于激光跟踪仪空间点坐标测量原理,利用回转工装寻找中间体轴孔圆心,测量两侧轴孔的圆心坐标,实现同轴度误差的测量。与传统经验设计的中间体相比,以拓扑优化为指导设计的中间体质量减少21.5%,静态刚度提高14.3%。光学法检测中间体两侧轴孔端面平行度误差为0.016 mm,两侧轴孔圆心位置偏差为0.03 mm。采用拓扑优化设计的中间体在提高刚度、降低惯量方面优势明显,提出的光学检测法可实现中间体形位公差的检测。

便携式形位公差检测演示教具的设计

本文主要介绍了便携式形位公差检测演示教具的设计过程,将形位公差中常用的11个项目列为检查项目,并根据各项目检测方式的不同,将其分为5个类型,按不同的类型完成演示教具相关组件的结构设计。并按照模块化思路设计,便于教具的安装于拆卸,可便于携带。

Analysis of Test Methods for Parts to Follow Relative Requirements

Testing the parts of mechanical products and ensuring their accuracy to the design requirements are essential to products’ quality, market competitiveness and manufacturers’ maximum economical benefits from these products. One of the latest subjects of study in the area of precision measurement is the testing of parts to follow the relative requirements, viz. design requirements for the size tolerance of size features and related geometrical tolerances of the central feature, including the envelope requirement, maximum material requirement and least material requirement. The article analyzes test methods for parts to follow the envelope requirement or maximum material requirement, as well as further requirements of geometrical tolerances for its central feature. The method is effective in improving product quality and rejecting unqualified parts.