Pole placement method on a class of nonlinear systems with adaptive backstepping technique

In this paper, a gain determining method for nonlinear adaptive backstepping technique is proposed by the pole placement method. By introducing a subsystem that can be linearised as a linear system, controller gains can be solved by the pole placement method. Compared with the existing techniques, the proposed method can achieve a transient performance like a linear system with the pole placement method instead of constraining the system in a predefined performance range. Meanwhile, the proposed method does not change the structure of adaptive backstepping controllers, which preserves the advantages of the original backstepping design and avoids increasing the computing effort for the control system. In addition, the applications of the proposed method are demonstrated by three examples, including a 2nd-order nonlinear system, a 3rd-order nonlinear system, and a single-link robot arm. The corresponding simulations are conducted, and the simulation results are illustrated and analysed. Moreover, comparative simulations are conducted to verify the proposed method.