Abstract
The robust servo system with robustness of output trajectories is analyzed and synthesized in the design of model reference ILQ (MR-ILQ) servo systems with the potential to achieve tracking robustness. Our purpose is to design a robust servo system with tracking robustness in that its output trajectory remains in a neighborhood of the nominal trajectory when the dynamics of the system is perturbed. For this purpose we first propose a robust L∞ performance measure for a fixed input in order to evaluate the worst-case value of the maximal amplitude of the error output response. By analyzing some related convex optimization problem described by linear matrix inequalities (LMIs), we next present a specific method to calculate this measure for the MR-ILQ servo systems. Based on this analysis, we then formulate a synthesis problem of minimizing this measure, and derive an LMI-based iterative algorithm to solve this synthesis problem. Finally we illustrate a numerical example to show the effectiveness of our results.
