Bounding truncation errors of a flexible slewing beam using DC gain for controller design

We develop a method of uncertainty modeling of a flexible slewing beam for robust controller design. The obtained uncertainty model consists of a finite dimensional nominal model and an uncertainty bound in the frequency domain. First, we review the conventional method by which a steady state solution to the original system is extensively utilized for bounding the error between the nominal truncated modal model and the original beam. Then as a main result, we establish a new error bound for the modal truncated model whose DC error is compensated. Numerical study demonstrates that, the error bound of the proposed nominal model is smaller than that of the conventional model in relevant frequency range, and thus, the proposed model leads to better control performance by a standard controller design.