Effects Due to Low Velocity Impact in Mechanical Oscillators

Phenomena caused by low velocity impacts in a class of forced impact oscillators are studied. It is shown that such impacts play an important role in the dynamics of general impacting systems. Features observed in numerical simulations of different oscillator models are associated with previous theoretical work on grazing impact. The Poincaré mapping geometry near points leading to low velocity impacts is shown, as well as bifurcations of types not found in nonimpacting systems. The consequences of not having a completely rigid constraint and the connection with the limiting case of a pure constraint are examined. In addition, low velocity impact in a Hamiltonian system is shown to have considerable effect on the break up of invariant tori.