Modal Analysis of Lumped Flexible Active Systems (Part 1)

Simulation and prediction of eigenfrequencies and resonance problems for flexible structures is an important task in disciplines such as robotics and aerospace engineering. However, little effort seems to have been put into the problem dealing with modal analysis of mechatronic systems containing coupled flexible structures and control systems. When, for instance, designing a satellite tracking radar, it is crucial to be able to predict resonance in the radar system during normal working conditions. Resonance may lead to loss of satellite tracking accuracy and long term fatigue problems. This paper addresses the theory of solving the eigenvalue problem for a simple one-degree-of-freedom system coupled with a single position feedback PD-controller. To test the theory, the nonlinear multidisciplinary simulation software FEDEM has been used. This paper is planned as the first in a series of papers addressing modal analysis of active flexible multibody systems.