Nonlinearity Estimation and Compensation for Robust Paths and Forces Control of Robot

For the control of nonlinear robot dynamics a centralized design method so called the method of the exact linearization and decoupling by state feedback is often used. This method has the disadvantage in that an extra out-loop robust control design is needed to handle varied operating conditions such as payload variations. In this research a new control model design based on fictitious linear dynamic of decentralized structure called nonlinearity estimation and compensation is described in which coupling effects and other nonlinearities are estimated by an extended state observer and counteracted using the concept of disturbance rejection control. The controller is structurally robust against the varied operating conditions. Simulation for nonlinear positions and forces results on a PUMA 560 robot manipulator [1] shows the advantages of this approach.