Experimental and theoretical investigation of a vibro-impact process utilizing an in situ capacitive distance measurement

摘要

A simplified non-linear vibro-impact process is investigated experimentally and theoretically. The system at hand is an ultrasonic vibrator hammering on an anvil. An experimental setup consisting of the vibro-impact system and a suitable phase control has been developed. Furthermore, an in situ capacitive distance measurement between the vibrators tip and the anvil has been developed. For this measurement a 2 MHz carrier signal is used, utilizing a complex voltage divider consisting of a reference capacity and the gap's complex impedance. The setup is used to validate models for vibro-impact systems. Hence one exemplary model-based description of such a system in terms of a finite element model of the ultrasonic oscillator including the mechanical and electrical degrees of freedom will be presented. The model is reduced and then solved in the frequency domain, linearizing the vibro impact process utilizing the harmonic balance method. Comparison of the experimental and theoretical results will conclude the contribution.