Global output feedback stabilisation for nonlinear systems via a switching control gain approach

This paper presents a novel approach to design the output feedback stabilising controller for a class of nonlinear systems. The considered system is in the strict-feedback form, and the nonlinear terms are allowed to depend on both the unmeasured states and the measured output. Meanwhile, the growth rate of the nonlinear term can be a general continuous function of the output, which is not required to be polynomial. We introduce a switching control gain approach and design the controller through considering the output feedback stabilisation based on a linear dynamic. It avoids a continuous update in a control gain. The effectiveness of this method is illustrated through a presented example in the end.