航天器大型空间桁架结构变形监测方法研究

Research on deformation monitoring method of large truss structure based on inverse finite element method

摘要:

大型空间桁架结构在航天器上有着广泛的应用；由于其具有质量轻、刚度低、阻尼小等特点,在受到扰动时可能发生振动和变形,影响载荷的正常工作甚至危害航天器的安全；以大型空间桁架的整体结构作为研究对象,对桁架结构的变形监测方法进行了研究；基于逆有限元提出了一种适用于桁架结构的变形监测方法,该方法以传感器测得的结构应变为基础重构桁架结构的变形；利用有限元仿真对该方法进行了验证,同时研究了在应变值存在误差的情况下形变重构的精度；结果表明,在应变值具有±5%的随机噪声时结构形变重构的误差优于±3%；该方法有较高的变形重构精度,对于航天器桁架结构的变形监测有重要的指导意义。

Abstract:

Large space truss structures are widely used in spacecraft; Due to its light weight, low stiffness and small damping, it is prone to vibration and deformation under disturbance, which will affect the normal operation of the load and even endanger the safety of the spacecraft; Taking the whole structure of large space truss as the research object, the deformation monitoring method of truss structure is studied; Based on the inverse finite element method, a deformation monitoring method for truss structure is proposed, which reconstructs the deformation of truss structure based on the structural strain measured by sensors; The method is verified by finite element simulation, and the accuracy of deformation reconstruction under the condition of strain valueerror is studied; The results show that the error of structural deformation reconstruction is no more than±3%；when the strain value has random noise ranging from±5%; This method has high deformation reconstruction accuracy and has important reference significance for deformation monitoring of spacecraft truss structure.