Impact dynamics near unilaterally constrained grazing orbits

International audienceThe dynamics of vibro-impact systems near grazing is known to be singular. The authors have recently exhibited nonlinearmodal motions in the vicinity of grazing orbits within a conservative framework, suggesting the latter play a important role in thedynamics. In this work, insights on the dynamics of solutions near some periodic grazing orbits are given. It is found that the firstreturn time may involve a square-root singularity or a cube-root singularity and also become discontinuous. These properties may affectthe first return map and thus the dynamics near grazing orbits