Design of Robust Controllers for Smart Structural Systems with Actuator Saturation

Abstract

The design and implementation of robust controllers on smart structural systems is often constrained by available control force of the actuators. The Lead Zirconite Titanate (PZT) actuators which are used for the control of flexible structures have limited control authority. The performance of the smart structural systems is often limited by the control effort constraint instead of the closed loop stability and performance. Due to the limited availability of control effort, it is desirable to utilize all of the control force in order to obtain the best performance. The research results described in this paper integrate robust control design methodologies with constrained actuator techniques for designing controllers for smart structural systems. In order to implement the proposed controllers, a two-dimensional lattice structure is designed and fabricated. The robust controllers in this paper have been designed for this test article. We have also developed the uncertainty modeling for this test article. An H₂/H. controller has been designed and implemented on the lattice structure. The experimental results of the closed-loop system and the verification of the robustness properties are also presented.

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References

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