Modal analysis of constrained multibody systems undergoing rotational motion

The modal characteristics of constrained multibody systems undergoing rotational motion are investigated in this paper. Relative co-ordinates are employed to derive the equations of motion, which are generally non-linear in terms of the co-ordinates. The dynamic equilibrium position of a constrained multibody system needs to be obtained from the non-linear equations of motion, which are then linearized at the dynamic equilibrium position. The mass and the stiffness matrices for the modal analysis can be obtained from the linearized equations of motion. To verify the effectiveness and the accuracy of the proposed method, numerical examples are solved and the results obtained by using the proposed method are compared with analytical and numerical results obtained by other methods. The proposed method can be used effectively for the design of constrained multibody systems undergoing rotational motion.