大孔径光学反射镜球铰支撑方式尺寸稳定性分析

采用球铰支撑可以极大地提高大孔径反射镜工作的可靠性,但必须对这种支撑方式进行合理的稳定性分析。球铰支撑方式的有限元分析必须围绕其支撑方式所具有的严格而又明显的接触特性、顶丝预紧力作用、具有相对滑动趋势而产生的摩擦这三大基本特征展开。应用传统的线性有限元分析手段对大孔径反射镜球铰方式支撑的尺寸稳定性分析具有较大的局限性。为提高分析精度,采用了非线性分析方法,最大程度地模拟实际结构,并将罚函数的摩擦形式引进到了摩擦接触对中,并对其进行了实际模型的解算,使得分析结果更加精确,并依据分析结果,对预紧力进行了合理地选取,使反射镜在一定的工作环境下能够稳定地工作,满足系统成像的需要。

Stability analysis to large aperture optics reflector with ball-hinge support means

Adopting ball-hinge support method,working reliability of large aperture reflector system can be enhanced extremely.It is necessary for this kind of support method to make reasonable stability analyzing.The structure simulation of ball-hinge support method must be processed around three basic characteristics,including distinct contact,pre-tension and friction brought from relative glide trend.The classical linear FEM has comparatively disadvantage to analyze stability of large aperture reflector system with ball-hinge support method.To enhance analyzing precision,nonlinear FEM is used.The actual structure is simulated farthest,and the friction form of penalty function is fetched in frictional contact coupling,which make the analyzing model and results more precise.Then the pre-tension is reasonably chosen according to the analyzing results,which make mechanics environment of the specula system more stable to reach the large aperture specula system imaging target.