空间薄壁式伸展臂的展开仿真与卷曲方式研究

针对一种完全依靠自身弹性展开的空间柔性薄壁式伸展臂的展开动力学问题，基于Kirchhoff Love基本假设和广义胡克定律推导了伸展臂各部分壳体在展开前的应力计算公式，使用该公式对伸展臂的有限元模型进行预应力初始化，并采用显式时间积分方法对正向卷曲、反向卷曲和不紧密卷曲的空间薄壁式伸展臂的展开过程进行了动力学仿真，通过实验对仿真结果进行了验证。研究结果表明：应力计算公式可以正确地计算薄壁式伸展臂在展开前的应力状态，基于预应力初始化方法的显式动力学仿真可以较为准确地模拟空间薄壁式伸展臂的展开过程；反向卷曲的伸展臂在展开过程中出现了向固定段展开的现象，并且具有较高的初始应变能，不利于薄壁式伸展臂的空间应用，在设计中应选择正向卷曲的方式；不紧密卷曲的影响主要表现为卷曲段内层壳体易于从卷曲段侧边缘滑出，使伸展臂在展开过程中产生较大幅度扭转，而增大壳体材料的摩擦系数则可以有效避免这种现象。

Deployment Simulation and Coiling Method Study of a Space Thin-Wall Deployable Boom

For the deployment dynamics problem of a space flexible thin wall deployable boom to deploy by its own elasticity, theoretical formulas are derived to calculate the stress distribution of the boom’s sections based on the Kirchhoff Love hypothesis and the generalized Hooke’s law. The formulas are used to initialize prestress of the finite element model of the deployable boom, and deployment dynamics simulations of the equal sense coiled, the opposite sense coiled and the incompactly coiled deployable boom are conducted by using the explicit time integration method. The simulation results are validated by experiments. It is shown that the formulas can accurately calculate the stress state of the space thin wall deployable boom before its deployment, and the explicit simulation based on prestress initialization method can accurately simulate the deployment of the boom; the opposite sense coiled boom will deploy to its clamped bottom and take more initial strain energy in the deployment process, which are harmful to the space application of the deployable boom, and therefore the equal sense coiling method should be chosen in the boom design; the incompactly coiling makes the inner shells tend to slide out from the side edge of the coiled section and the boom produce large torsion, which can be effectively avoided by increasing the friction coefficient of the boom’s material.