Abstract: The problem of the multiple impacts of double flexible rods is studied. The theoretical solutions of the transient wave responses of the two rods are obtained for the processes of impacts and separations, based on the expansion of transient wave functions in a series of eigenfunctions for the St. VENANT rod. The multiple-impact force is derived from the interfacial stress at the contact ends. The interfacial stress is calculated from the solutions of the transient wave response of a temporary combined rod system during impacts. Therefore, the problem of the multiple impacts of double flexible rods is solved reasonably. The numerical results show that the effects of the transient wave propagation induced by impacts are fully considered. The present solution can obtain the multiple-impact force responses and the transient wave responses. The phenomenon of the transient wave propagation and the “sub-impact” can be found numerically as well. The effects of the initial impact velocity on the impact responses are investigated, and the numerical results show that there are some complex physical mechanisms on the multiple impacts. It is shown that the present solution can simulate reasonably the processes of multiple impacts, and the solution methods can be applied to the multiple-impact phenomena taken place in wider flexible mechanical systems.

Key words: Impact force, Multiple-impact, Transient response