Systematic approach to selecting H_∞ weighting functions for DC servos

This paper proposes an experimental solution for H_∞ weighting functions selection by exploring an experimental planning method which is widely used in quality control. Conducting matrix experiments via orthogonal array, several parameters in H_∞ weighting functions can be determined efficiently so that the resulting controller is able to satisfy all design specifications. Of great importance, the proposed experimental method provides additional robust performance property to conventional H_∞ control which can only prove robust stability and nominal performance. Velocity controller design of DC servomotors is demonstrated to show the remarkable robustness and superior servo performance provided by experimental H_∞ design. A hardware environment is constructed to correlate the theoretical prediction and the measurement data. All specifications of robust stability and performance are validated by the experimental results.