H/spl infin/ Control of Nonlinear Systems with Common Multi-channel Delays

A generalized H_infin controller is derived for the control of nonlinear, possibly time-varying, multivariable systems with common output or input channel delays. A nonlinear generalized minimum variance (NGMV) controller has recently been proposed for plants modelled by a combination of linear and nonlinear subsystems, where the disturbance and reference models are linear. The aim in the following is to obtain a related controller but one which minimizes an H_infin norm, to enable sensitivity functions to be shaped. The cost-function to be minimized involves both error and control signal costing terms, which are related to sensitivity and control sensitivity costing terms