Orientation Control of an Object on a Rotating Base by Using a Two-Stage Electric Drive

In this paper, we study the process of controlling the rotation of an object relative to a rotating base using a two-stage electric drive that represents two gearless direct-current motors connected in series. The stator of one of the electric motor is rigidly fixed to the base while an object is fixed to the rotor of the other motor. Between the rotor and the stator of the second motor, there is a torsion spring (torsion) with a relatively low level of stiffness. The aim of the control is tracking by an object a specified orientation relative to the base. The drive control algorithm is built taking into account the incompleteness of the information on the dynamic parameters of the mechanical system, friction acting in it, laws of motion of the base, and changes in the tracked orientation.