Adding a power integrator: a tool for global stabilization of high-order lower-triangular systems

A feedback design tool called adding a power integrator is introduced and used to solve the problem of global robust stabilization, for a significant class of uncertain nonlinear systems that are of a lower-triangular form but neither necessarily feedback linearizable (fully or partially) nor affine in the control variables, and therefore cannot be dealt with via conventional approaches. Sufficient conditions are presented under which a globally stabilizing smooth state feedback control law can be explicitly constructed, using repeatedly the adding one power integrator technique. This novel design technique permits removal of the feedback linearizability and linearity of the control input, which have been two common assumptions so far in the literature of nonlinear control