Identification of chaotic phenomena in a flexible deployable solar panel with multiple clearances

Deployable solar panels are widely used in spacecraft, and the dynamic characteristics of the deployment process directly affect the accuracy, stability, and reliability of the deployment. The flexibility and hinge clearance of a solar panel are important factors affecting the dynamic characteristics of the deployment system. The finite element method (FEM) was used to deal with the deformations of the solar panel. A dynamic model of the deployment process of a flexible solar panel with multiple clearances was established by combining the Lagrange equation with the FEM. The dynamic characteristics of solar panel deployment with multiple clearances and flexibility coupling were analyzed through a numerical solution, and the chaotic phenomena caused by clearances were identified. The results show that reasonably matching the clearance and flexibility of the system structure could quickly stabilize the collision force, improve the system life, and effectively improve the stability of the solar panel deployment process. Chaotic phenomena could be induced by the deployment velocity in a certain range, and the boundary value of the range changed with different clearance radii. The velocity variation law inducing chaotic phenomena also varied with the radius of clearance. This research provides important guidance for the optimum design and manufacturing of deployable solar panel mechanisms.

Chaotic Phenomena and Nonlinear Responses in a Vibroacoustic System

This study addresses the chaotic phenomena and nonlinear responses in a vibroacoustic system. It is the first study about the chaotic phenomena in a vibroacoustic system, which is formed by a flexible panel coupled with a cavity. A multimode formulation is developed from the acoustic governing equation and nonlinear structural governing equation. The chaotic and various nonlinear responses are computed from the multimode formulation using a numerical integration method. The results obtained from the proposed method and classical harmonic balance method are generally consistent. A set of modal convergence studies is performed to check the proposed method. The effects of various parameters on triggering the nonchaotic responses to chaotic responses in a vibroacoustic system are studied in detail.

Probing the chaotic boundary of a membrane resonator with nanowire arrays

Mechanically induced nonlinearities in nano-electromechanical systems (NEMSs) are typically avoided in design due to their unpredictable nature; however, by incorporating these normally unwanted nonlinear and chaotic phenomena, the performance of NEMS devices displays substantially different characteristics opening a broad new range of potential applications for their use.