智能太阳翼有限元建模与振动控制研究

RESEARCH ON FINITE ELEMENT MODELING AND VIBRATION CONTROL FOR SMART SOLAR ARRAY

采用空间梁单元和矩形层板单元建立了表面粘贴压电片太阳翼的机电耦合有限元模型。其中,太阳翼与星体之间的连接架、太阳翼基板间连接铰链按空间梁单元处理;不含压电片的太阳翼基板按普通层板单元处理,而含有压电片的基板按压电层板单元处理。推导了多点约束关系式处理空间梁单元和板单元公共节点自由度不协调的问题。利用速度负反馈和线性二次最优调节器设计控制系统,编制有限元分析程序,进行了动力学特性计算和振动控制数值仿真。结果表明,压电传感/作动器的引入对太阳翼振动频率具有重要影响;利用压电传感/作动器和最优控制系统能够有效抑制太阳翼的振动。

The finite element model coupled with the mechanical and electrical response of the solar array with piezoelectric sensors and actuators was presented. The tripod and the joints of the solar array were modeled using the 3D beam element, and the panels of the solar array with piezoelectric sensors and actuators were modeled using the piezoelectric laminated plate element. The multi - point constrained relations have been derived, which can deal with the inconsistent problem of the degree of freedom for the common nodes of the plate element and the 3D beam element. The analysis program of the finite element model has been coded. The negative velocity feedback controller and the linear quadratic regulator （LQR） were employed to investigate their effectiveness in suppressing the vibrations of the smart solar array. Numerical examples on vibration frequencies analysis and the vibration control have been developed. The piezoelectric sensors/actuators will influence the dynamic characteristics of the solar array significantly. The vibration of the smart solar array can be suppressed effectively with LQR controller.