Sensitivity of Structural Models for Noncollocated Control Systems

This paper investigates sensitivity properties of structural models pertinent to robust control system design. Special emphasis is put on noncollocated systems. Sensitivity analysis to parameter variations and boundary conditions is performed on a representative example of a pinned-free beam with end-point mass and inertia and sensors distributed along the beam. The analysis utilizes a transfer matrix representation, which provides a convenient form for demonstrating the sensitivity of zeros and poles to sensors locations and system parameters. Investigation of the applicability of different structural models is also carried out. Comparison of the Euler-Bernoulli theory and Timoshenko beam theory is discussed and the range of parameters for which each theory is applicable is demonstrated.