Thermally induced vibrations in inflatable space structures: theory and experiment

将宇宙飞船送入轨道的主要障碍之一是它们高昂的发射成本。因此，重量一直是航天工业的一大设计关注点。充气技术是一种很有前途的解决方案，可以在太空中放置大型计量系统，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，这些系统可以在发射时压缩成几英寸厚的折叠堆栈，并可以充气并部署在数百英尺的太空中。由于这些结构是在发射期间堆放的，只有在到达目的地轨道后才会展开，因此空间中的临界载荷和扰动尤为重要。这与老式卫星不同，老式卫星的大多数关键载荷都是在发射时满足的。环境扰动最重要的来源之一是穿过地球阴影时遇到的快速温度变化。这种干扰可能会在结构中引起弯矩和扭矩，导致热振荡，从而破坏卫星系统的指向精度和精度，并可能持续几个小时到一年的任何时间。因此，这项研究的一个主要目标是开发新的分析和实验技术，用于研究和表征充气结构的一些主要部件上的热负荷，如刚性吊杆和Mylar膜。这项研究将研究这些材料对快速温度变化的动态响应。充气结构的实验技术以及补充的建模方法代表了这项工作的新方面，将对我们理解充气结构的热动力学行为做出重大贡献。研究结果将被用于开发控制技术，以最大限度地减少此类系统对热扰动的敏感性。拟议的研究计划旨在培训下一代HQP在结构振动和控制方面，以及COM DEV国际有限公司、MDA和加拿大空间计划等工业公司所需要的实验应用。

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.