A Novel Dynamic Model of the Straight Beam Using the Rigid Body Element Method

In this paper, a novel dynamic model of the straight beam is proposed based on the rigid body element (RBE) method. Firstly, the beam is divided into a set of rigid body elements (RBEs), and two adjacent elements are contacted by an elastic joint (EJ), which is modeled through six imaginary springs. Secondly, the stiffness of an elastic joint (EJ) is calculated using cross-section parameters between two adjacent elements, and interaction forces and moments can be obtained. Then, equations of motions of each rigid body element (RBE) are given based on Newton–Euler equations. Finally, vibration is obtained through the fourth-order Runge–Kutta–Fehlberg method with a step-changing criterion, and the proposed model is verified by the finite element model (FEM).