Design of the observer-based cross-coupled positioning servodrives

A novel structure of cross-coupled observer based control system, proposed in this paper, is accomplished by the digital simulation of friction and stiffness of a virtual mechanical link (electrical shaft), which couples two electrical drives. Angle positions of the cross-coupled servos are controlled by the common digital controller. Angular positions of shafts of the drives are measured in a digital form. The samples of measured angle positions are used to estimate feedback variables (shaft speeds) by the observers. The suitable procedures are proposed for setting of controller parameters with respect to the desired system continuous-time responses. Results of several simulation runs are given to prove advantages and the most important features of the proposed system structure and to verify the analytical investigations.