A simplified approach to the design of nonlinear disturbance observer for axial motion systems

For more precise applications, axial motion systems have to be controlled for reducing uncertain perturbations of systems. However, the present control algorithms are difficult to deal with because of the highly nonlinear and unknown properties of uncertainties. Although some control algorithms are used to effectively degrade the uncertainty effects, the copious process and the complicated computation limits the application in real motion systems. In this paper, a simple compensation method is proposed to effectively degrade the uncertainty effects of axial motion systems by applying the nonlinear disturbance observer and compensator. The design of nonlinear feedback velocity loop and its stability analysis are also discussed in detail