Thermally induced vibrations in inflatable space structures: theory and experiment

将航天器送入轨道的主要障碍之一是高昂的发射价格。因此，重量一直是航天工业设计的主要关注点。充气技术是一种很有前途的解决方案，可以将大型计量系统放置在太空中，以满足其发射体积和质量目标。这项新兴技术提供了重量轻、可存放和可部署的卫星系统，在发射时可以压缩成几英寸厚的折叠堆，可以充气并在数百英尺的太空中展开。由于这些结构是在发射期间装载的，只有在到达目标轨道时才会展开，因此空间中的临界载荷和扰动尤为重要。这与较老的卫星形成对比，后者在发射时就满足了大多数关键载荷。环境扰动最重要的来源之一是在穿过地球阴影时遇到的快速温度变化。这种扰动会引起结构中的弯矩和扭矩，从而导致热振荡，从而破坏卫星系统的指向精度和精度，并且可以持续几个小时到一年的任何时间。因此，拟议研究的一个主要目标是开发新的分析和实验技术，以调查和表征充气结构的一些主要部件的热负荷，如刚性臂和聚酯膜。本研究将探讨这些材料对快速温度变化的动态响应。实验技术以及充气结构的互补建模方法代表了这项工作的新方面，并将对我们理解充气结构的热动力学行为做出重大贡献。研究结果将用于开发控制技术，以尽量减少这种系统对热扰动的敏感性。拟议的研究计划旨在培养下一代HQP在结构振动和控制方面的能力，并在COM DEV国际有限公司、MDA和加拿大空间计划等工业公司的需求下进行实验应用。

One of the main obstacles to placing spacecrafts in orbits is their high price for launch. Therefore, weight has always been a major design concern for space industry. Inflatable technology is a promising solution for placing large metrology systems in space to meet their launch volume and mass goals. This emerging technology offers lightweight, stowable and deployable satellite systems that can be compressed into folded stacks of a few inches thickness during launch and can be inflated and deployed over hundreds of feet in space. Because these structures are stowed during launch and deployed only upon reaching the destination orbit, the critical loads and disturbances in space are of particular importance. This is in contrast with older satellites for which most critical loads are met during launch. One of the most important sources of environmental disturbance is the rapid temperature change encountered on passing through the Earth's shadow. Such disturbances can induce bending moments and torques in the structure which result in thermal oscillations that can corrupt the pointing accuracy and precision of the satellite system and can last anytime from a few hours to a year. Therefore, a major objective of the proposed research is to develop novel analytical and experimental techniques for investigation and characterization of thermal loads on some of the major components of inflatable structures such as rigidized booms and Mylar membranes. This study will investigate the dynamic response of these materials to rapid temperature changes. The experimental techniques along with complementary modeling methods for inflatable structures represent novel aspects of this work and will make a significant contribution to our understanding of the thermal dynamic behaviour of the inflatable structures. The results will be used to develop control techniques to minimize the susceptibility of such systems to thermal disturbances. The proposed research program is intended to train the next generation HQP in structural vibration and control, with experimental applications which are in demand by industrial companies such as COM DEV International Ltd., MDA and the Canadian Space program.