Analytic nonlinear H-infinity inverse-optimal control for Euler-Lagrange system

Recent success in nonlinear H-infinity control design is applied to the con trol of Euler-Lagrange systems. It is known that the existence of H-infinit y optimal control depends on solvability of the so-called Hamilton-Jacobi-I saccs (HJI) partial differential equation. In this article, the associated HJI equation for nonlinear H-infinity inverse-optimal control problem for E uler-Lagrangian system is solved analytically. The resulting control is ref erred to as the reference error feedback, which takes conventional PID cont roller form. Consequently, robust motion control can be designed for robot manipulators using L-2-gain attenuation from exogenous disturbance and para metric error.