Dynamics of a Drifting Impact Oscillator with a Conical Profile

A new model of the progression phase of a drifting oscillator is proposed to account more accurately for the penetration of a conical impactor through elasto-plastic solids under a combination of a static and a harmonic excitation. The dynamic response of the semi-infinite elasto-plastic medium subjected to repeated impacts by a rigid impactor with conical contacting surface is considered and a power law force–penetration relationship is adopted to describe the loading and unloading phases of contact. These relationships are then used to develop a physical and mathematical model of this drifting oscillator, where the time histories of the progression through the medium include both the loading and unloading phases. A limited nonlinear dynamic analysis of the system was performed and it confirms that the maximum progressive motion of the oscillator occurs when the system exhibits periodic motion.