Experimental verification of the vibro-impact capsule model

In this paper, an experimental verification of the vibro-impact capsule model proposed by Liu et al. in (Int. J. Mech. Sci, 66:2-11; 2013a, Int. J. Mech. Sci, 72:39-54; 2013b, Int. J. Non-Linear Mech., 70, 30-46; 2015) is presented. The capsule dynamics is investigated experimentally by varying the stiffness of the support spring, and the frequency and the amplitude of excitation. The novel design of the experimental set-up is discussed, and comparisons between the experiments and numerical simulations are presented showing a good agreement. The conducted bifurcation analysis indicates that the behaviour of the system is mainly periodic and that a fine tuning of the control parameters can significantly improve the performance of the system. The main findings provide a better insight into the vibro-impact systems subject to nonlinear friction, and the experimental rig can be used to predict the dynamic behaviour of these systems.