Nonlinear feedback control of a HIV-1 infection model

Nonlinear feedback is investigated to define control strategies for a nonlinear model of HIV-1 model. The proposed control architecture comprises two feedback loops, the inner loop is used to obtain a linear dynamic model using the number of virion particles and the total of CD4+T cells, and the outer loop is used as a supervisor that defines and adjusts the command for the inner loop to attain the target reference. The nonlinear controller is developed in the continuous time frame work, where the total of CD4+T cells (healthy and infected) and the number of virion particles are measured continuously. This paper considers just the administration of RTI drugs for the sake of simplicity in explaining the methodology proposed, that is, the direct manipulation of the efficiency of the drugs. A discrete time version is also presented. The nonlinear control law enables a decoupling between the dynamics of healthy, infected cells and the virion particles, and it also enables the identification of useful parameters that help the supervisor to handle parameter uncertainty. Stability analysis shows that proposed control law stabilizes the nonlinear HIV-1 model.