Adaptive /spl lambda/-tracking for nonlinear systems with higher relative degree

Previous results for adaptive /spl lambda/-tracker have focused on nonlinear systems with relative degree one or on linear systems with higher relative degree. We extend the adaptive /spl lambda/-tracker to /spl lambda/-stabilize nonlinear system with higher relative degree. Only little structural information about the system to be controlled is needed. /spl lambda/-stability and convergence of the adaptation is proven for tracking a large class of reference trajectories. The design of the controller is very simple and intuitive, only few parameters have to be tuned.