Equivalent Input Disturbance Based Robust Control For Robot Manipulator Using Generalised Extended State Observer

Abstract

This paper presents, Equivalent Input Disturbance (EID) based robust control for Robot Manipulator (RM) under uncertain conditions. Robust control is achieved by designing the Generalised Extended State Observer (GESO). Modern control designs typically requires a complete state vector for their implementations as well as estimation of uncertain states. However above mentioned requirement are difficult to meet in a real life system. To fulfil aforementioned requirements a GESO is developed that simultaneously estimates the state vector and the uncertainty. To begin the nonlinear dynamics of a robot manipulator are modelled using a linear formulation that includes uncertainty and disturbances. Then for disturbance rejection an EID + GESO based control is presented. Uncertainty and disturbances are addressed as a single lump disturbance called EID which is effectively attenuated using GESO and state feedback. The approach closed loop stability is also proven. The method is then deployed to a robot manipulator and its usefulness is demonstrated using numerical simulations under significant uncertainty and disturbances to illustrate the efficacy and robustness of the suggested design.