Abstract:The problems of stability regions estimation, observer design, and adaptive feedback control for a class of the continuous differential equation models of the interaction dynamics of HIV-1 and CD4 and CD8 lymphocytes in the human body are investigated. First, the output feedback control law is derived such that in the closed-loop system, the states that represent CD4, CD8 and viral load, can be regulated to a specified equilibrium point in the state space. The stabilizing controller is analogous to require only finite and little therapeutic drug regimen. Furthermore, since the CD4 and CD8 populations in a human have a typical range of equilibrium values, a T-S fuzzy model will be employed to monitor the lymphocyte counts. Finally, due to the exact information about the equilibrium may not be available, we will propose a linear adaptation law and examine the conditions under which it achieves the stabilization of the unknown equilibrium.