Stable adaptive control of manipulators with improved transients via supervision of the free-design parameters and sampling period

An adaptive control scheme for mechanical manipulators is proposed. The control loop consists of a network for learning the robot´s inverse dynamics and online generating the control signal. Some simulation results are provided to evaluate the design. A supervisor is used to improve the performances of the system during the adaptation transients. The supervisory exerts two actions. The first one consists of updating the free-design adaptive controller parameters so that the value of a quadratic loss function is maintained sufficiently small. The second action consists of an on-line adjustment of the sampling period within an interval centered at its nominal value.