An alternative stability proof for robust control of electrically driven robots using adaptive uncertainty estimation

Abstract

This paper points out an improvement on the robust stability analysis for electrically driven robots given in the paper “robust control of electrically driven robots using adaptive uncertainty estimation”. In the aforementioned paper, a robust adaptive control scheme for electrically driven robots has been presented. The uncertainties have been estimated and compensated using Taylor series expansion. The nonlinearities associated with actuator input constraints have been considered in that paper. It discussed the saturated and unsaturated region of the control input separately and neglected the transition state between these regions. Moreover, it did not guarantee the stability of the closed-loop system in the saturated area. In this paper, an alternative stability proof is presented that do not require this separation and guarantee the stability in a more general framework. Moreover, in the performance evaluation, the upper bound for the error vector of Taylor series coefficients estimations is calculated.