结合空间索杆铰接式伸展臂在航天工程中的应用,基于伸展臂从航天器伸出且前端支撑负载的在轨工作状态,运用欧拉梁理论建立了悬臂式伸展臂理论分析模型。分析了工作状态下伸展臂与负载系统的固有频率和根部弯曲强度,提出了基于伸展臂固有频率限制和根部弯矩限制的伸展臂参数设计方法。通过算例分析了伸展臂线密度、半径、纵杆截面面积等主要设计参数与伸展臂固有频率和根部弯矩之间的关系。研制了伸展臂原理样机,其弯曲刚度和抗弯强度分别为0.388 MN.m^2和562.12 N.m,验证了伸展臂具有较高的刚度和强度。对伸展臂物理样机的地面重复展开定位精度进行了测量实验,其轴向、水平、竖直方向上的重复展开精度分别为0.127 mm、0.645 mm和0.588 mm,证明了伸展臂具有较高的重复展开定位精度。
A theoretical analysis model for a space cable-strut deployable articulated mast worked at its on-orbit state was developed by using Euler beam theory,which aimed to a working state that the mast was extended out the spacecraft and its load mass was supported by the mass tip.The natural frequency and the root bending strength of the mast when mast worked on-orbits were analyzed.The primary parameter design method of the mast were studied based on the natural frequency constraint and root moment constraint,then the relationships between the primary design parameters of the mast such as line density,mast radius,longeron section area and the natural frequency and the root bending moment were discussed through calculation examples.A prototype of space cable-strut deployable articulated mast was developed,and its bending stiffness and bending strength are 0.388 MN·m^2 and 562.12 N·m,respectively,which validates that the mast has very high bending stiffness and strength.Meanwhile,the repetitive deployable orientation precision of the mast prototype was measured on the ground.Results show that the mast prototype can offer higher repetitive precisions in 0.127,0.645 and 0.588 mm for axis,horizontal and vertical directions,respectively.