On motion stabilization of a mechanical system with cyclic coordinates

In the paper, mechanical systems with cyclic coordinates are considered. Such systems admit the existence of steady and unsteady motions (stationary and generalized stationary), in which the positional coordinates are constant and the cyclic ones change in time according to linear or nonlinear laws. The problems of complete and partial stabilization of such motions are solved using only (all or positional) generalized coordinates measurements. The solution to the motion stabilization problem is given using nonlinear PI and PID regulators. As an example the stabilization problem of a space three-link robot manipulator is solved.