Experimental and numerical investigation of impacting cantilever beams: Second mode response

•Experimental and numerical study of impacting beams for primary beam second mode.•Model correlates well with experiments for high amplitude excitation.•Lower amplitude excitation causes intermittent contact in experiments.•Period doubling route to chaos around second mode of the primary beam.•Differentiation of measured velocity using filters not correct for vibroimpacts.

The dynamics of a cantilever beam undergoing vibro-impact, near its second linear natural frequency, is the focus of this paper. The flexible beam undergoes vibro-impact with two other flexible beams at its free end. Both experimental and computational methods are used for the study. From this it is shown that the computational model is able to capture the experimental vibro-impact behavior very well when the excitation amplitudes are reasonably high. Further, the presence of chaos through the period doubling route is demonstrated in the experimental studies. By using independent acceleration and velocity measurements, it is demonstrated that smoothing filters suggested in the literature for generating derivatives (acceleration from velocity) does not work very well for vibro-impact problems.