Resonance Behavior Analysis Of X Configuration Tension Nonlinear Systems

Compared with other kind of solar arrays,circular solar arrays have attracted more and more attention at home and abroad because of the advantages,such as large absorption ratio,high power to mass ratio and high deployable stiffness.An important component of the circular solar wing is the tension regulating unit.The mechanism of the tension adjusting unit in the tension mechanism is to transform the spring tension parallel to the direction of the rib into the tension perpendicular to the direction of the rib under the action of the Kevlar rope.The tension mechanism has typical nonlinear characteristics because of that.The analysis of the working principle and dynamic characteristics of the tension mechanism can provide a reference for the design of the tension mechanism and even the design of the circular solar wing.Therefore,the tension mechanism is a worthy research.In order to analyze the influence of tension mechanism,the circular solar array is simplified as a nonlinear two-degree-of-freedom model with only one tension adjusting element.The analysis and calculation are carried out from the aspects of tension spring stiffness,film equivalent stiffness,damping ratio,excitation frequency and excitation amplitude.1.By analyzing the force and deformation of the tension adjusting element,the nonlinear model of the tension adjusting element is established.It can provide reference for the parameter design of the tension mechanism.2.The dynamic characteristics of the two-degree-of-freedom symmetric structure with tension nonlinear under asymmetric excitation were studied.The results show that the multi-solution interval of the structure appears in the position after the resonance frequency in the amplitude-frequency characteristic curve,and appears in the position with the low excitation amplitude in the excitation amplitude-vibration amplitude curve.When the excitation of the tension mechanism cannot be eliminated,the phenomenon of multiple solutions can be avoided by reducing the excitation frequency as much as possible.3.For the two-degree-of-freedom asymmetric structure with tension nonlinear,we obtained the change of the system response by applying the same excitation to the fixed ends of the two ribs and the asymmetric response caused by the structural geometric parameters.We also analyzed the structure response under the change of damping ratio and excitation amplitude changing.Dynamically speaking,adding dampers between the two ribs of the tension mechanism can strictly control the excitation frequency of the structure below the natural frequency of the structure,so as to avoid the phenomenon of multiple solutions in the system response.However,from an engineering point of view,increasing the damper and reducing the excitation frequency both need to be discussed in terms of developing new materials and new structures.