Finite element analysis and high-precision molding of a novel panel unit based on the Leighton Chajnantor Telescope

Abstract The submillimeter band (0.35–1.00 mm), situated between the infrared (IR) and radio wave bands, offers unique advantages for astronomical observations by penetrating interstellar dust more effectively than the near-IR band and providing higher spatial resolution than the microwave band, making it invaluable for studying cosmic objects. However, existing radio telescope reflector panels, such as solid aluminum alloy panels, aluminum honeycomb structural panels, and aluminum-skinned honeycomb panels, often suffer from challenges like stress deformation and accuracy instability, as seen in panels used at the Leighton Chajnantor Telescope in Chile. To address these limitations, this study presents an innovative panel unit for a 3 m submillimeter-wave telescope, designed for high precision, low cost, and minimal temperature sensitivity. The structure integrates 1060 and 6061 aluminum alloys for the exterior and honeycomb core layers, respectively, mitigating issues like oxidation and corrosion-induced detachment. ANSYS modeling and optimization determined a diameter-to-thickness ratio of $D/h = 7:1$ (D = 500 mm, h = 72 mm) to achieve optimal face shape accuracy, ensuring superior optical performance at varying elevation angles. The design exhibits minimal sensitivity to temperature fluctuations, maintaining root mean square (RMS) values below 10 µm in both high- and low-temperature environments. Fabrication employs cemented honeycomb construction, CNC aspherical machining, and single-point diamond turning to enhance the surface precision while reducing costs. The fabricated panel achieved RMS values of 8.37 and 8.21 µm in low- and high-temperature tests, respectively, validating its effectiveness and offering a robust, cost-efficient solution for enhancing submillimeter-wave telescope performance.