Optimal periodic motions of two-mass systems in resistive media
Progressive motions of two-mass systems in resistive media are analyzed. The motion control is implemented by means of periodic relative displacements of the masses. Different kinds of resistance forces acting upon the system are considered including linear and nonlinear resistance depending on the velocity as well as Coulomb's dry friction forces. Constraints are imposed upon the relative displacements and velocities of the masses. Optimal periodic motions are determined that correspond to the maximal average speed of the system as a whole. Experimental data confirm the obtained theoretical results. Models of mobile mini-robots are described which are based on the principle presented in the paper.