The activities presented under this paper were focused on designing, manufacturing, testing and evaluation of a metallic antenna reflector for space applications. The main challenge was to obtain a low mass, while maintaining the reflector capability to withstand the mechanical loads encountered during the launching phase, as well as the harsh space environment with significant temperature variations, without any detrimental effect over the dimensional stability of the reflective surface. The chosen material was titanium alloy for the reflector and stainless steel for fasteners and mounting supports. Manufacturing parameters have been investigated aiming for low internal stresses during processing and to obtain the best results in terms of dimensional accuracy and surface roughness. One of the five analysed reflector architectures (reflector breadboards) was selected and manufactured using two different finishing operations, milling and turning, the latter being the one presenting the best results. Dimensional accuracy of the reflector breadboard, before and after vibration and environmental tests, was found to be smaller than the imposed requirements, thus validating the reflector proposed design. After the breadboarding activity, an optimized version of the antenna reflector (demonstrator), also validated by structural analysis, was developed. Unfortunately, the measured profile deviation of the demonstrator was higher than the imposed requirements (by 50%), mainly due to internal stresses during mechanical processing of the new geometry. Before the experimental evaluation of the reflector demonstrator, a surface coating was developed and applied to the reflective surface of the demonstrator. Despite the profile deviation, the demonstrator meets the imposed mechanical requirements and offers important lessons to be applied in the future development activities.

本文介绍的活动重点在于用于太空应用的金属天线反射器的设计，制造，测试和评估。主要挑战是要获得低质量的产品，同时保持反射镜的能力以承受发射阶段遇到的机械负载以及温度变化显着的恶劣空间环境，而不会对反射面的尺寸稳定性产生任何不利影响。选择的材料是用于反射镜的钛合金，以及用于紧固件和安装支架的不锈钢。为了降低加工过程中的内部应力，并针对尺寸精度和表面粗糙度获得最佳结果，已经对制造参数进行了研究。选择了五种经过分析的反射器结构（反射器面包板）中的一种，并使用两种不同的精加工操作（铣削和车削）进行制造，后者表现出最好的效果。发现在振动和环境测试之前和之后，反射器面包板的尺寸精度小于所施加的要求，从而验证了反射器建议的设计。电路板活动之后，开发了天线反射器（演示器）的优化版本，并通过结构分析对其进行了验证。不幸的是，演示器的测得轮廓偏差高于规定的要求（高出50％），这主要是由于在新几何结构的机械加工过程中产生的内应力。在对反射镜演示器进行实验评估之前，开发了表面涂层并将其施加到演示器的反射表面上。尽管轮廓有所偏差，但演示器仍满足所施加的机械要求，并提供了重要的经验教训，可用于将来的开发活动。