Investigation of Dynamics of a Pipe Robot with Nonlinear Interactions of Its Elements

Systems in which vibrational displacements are limited because elastic forces increase practically up to unlimited values, are investigated. Here systems having one degree of freedom are investigated in which vibrations have specific qualities for the case of conservative systems as well as for the case of forced harmonic excitations. Typical expressions for nonlinear stiffness are proposed. Model of a pipe robot with limited values of displacements is presented and investigated. The model has two degrees of freedom: the displacement of the vibrating mass inside the pipe robot and the displacement of the pipe robot itself. Motion of the pipe robot in the negative direction as well as motion of the pipe robot in the positive direction for different parameters of the system is observed. For high amplitude of excitation, the distance travelled by the pipe robot is much greater than for low amplitude of excitation. The obtained results are used in the process of design of pipe robots.