Nonlinear self-defined truss element based on the plane truss structure with flexible connector

A finite-element method based on the self-defined truss element is developed to model the plane truss structure with the flexible connector, and the dynamic characteristic of the corresponding model is analyzed in this paper. Firstly, a new type truss structure with flexible connectors included clearance, friction and axial constraint is analyzed. A self-defined truss element is defined based on the mechanical analysis of the new type truss structure, and a finite-element model is introduced based on this element. The nonlinear elastic-damper model and the Coulomb friction model are adopted to analyze the nonlinear nodal forces from the impact and friction in the clearance field. Secondly, a modified numerical solution method is developed based on the Newmark implicit integrate method together with Newton-Raphson iterated method, and then is applied to solve the nonlinear dynamic model. Finally, an example is simulated by the above numerical method, and the effects of several key parameters (such as the linkage stiffness, contact stiffness, and clearance) on the dynamic characteristic are analyzed. The results validate the numerical method, and show the effectiveness of the nonlinear finite-element model. The dynamic analysis about the key parameters offers some helpful guidelines for designing flexible truss structure.