Inverse dynamics control method applied to the standard servo control system to suppress two-mass system vibration

This paper describes a method for two-mass system torsional vibrations suppression. These vibrations are evoked due to torsion plasticity of mechanism kinematical chain links and large moment of inertia. This strategy belongs to the group of feedforward control techniques. By means of the knowledge about the system parameters and the two-mass system mathematical model it is easy to derivate its transfer function. The main idea of this method is to create the inverse transfer function of problematic second mass of the system and use it in the control structure as a feedforward controller. And in this way suppress the activity of system imaginary poles that cause the residual vibrations. This method was firstly tested on mathematical model simulations and then integrated into the cascade structure of standard servo control unit Siemens Sinamics S120. The results from experiments demonstrate the ability of this method to effectively compensate the torsional vibrations of the mechanism end-link