Optimal Design of Support System for the Large-aperture Sphere Mirror
大口径球面镜支撑系统的优化设计

The support system of the 1.2 m sphere mirror was optimum designed by the finite element method.For the analysis,the axisymmetric finite-element mesh and 3D solid finite-element model were used by the finite element software.The support-ring number,the support-ring radius,the axial support point configuration and the lateral support position were determined after the optimum design.The mirror deformation were calculated when the telescope pointing to the zenith and the horizon.In these two conditions,the surface figure deformation root-mean-square (RMS) values were 2.5 nm and 3.16 nm respectively,which satisfy the requirement and show that the support system is feasible.