New class of adaptive control laws for robot manipulators

In the past, several adaptive control methods based on the computed torque schemes using the Lyapunov stability theory have been proposed. However, most of the methods proposed to date, based on the computed torque schemes, have only integral adaptive laws. This paper presents a new adaptive controller based on the computed torque schemes using Popov hyperstability theory. The manipulator adaptive control problem is first formulated in a form suitable for the application of hyperstability theory. The adaptation law is general, and most of the adaptation laws which have been proposed based on computed torque schemes are special forms of this adaptation law. The adaptive controller takes advantage of the flexibility in the choice of the adaptive parameters. The adaptation laws guarantee globally asymptotic stability. Simulation results are presented to evaluate the performance of the adaptive controller for a two-link manipulator.