System structure configuration and actuator degradation

In this paper the choice of input-output pairing for multivariable systems in the event of channel-specific actuator degradation is addressed. A measure of subsystem interaction is proposed, defined in terms of H_∞ norm of individual subsystems of the plant. Based on this interaction index some guidelines are proposed for input-output pairing when there is actuator degradation in a channel. The approach is proposed for open loop stable multivariable systems. Simulation results are included demonstrating the effectiveness of the proposed interaction index. The proposed approach recommends the least affected pair for a multivariable system and its performance measure defined in terms of Root Mean Square Error (RMSE) is minimum.