Investigation of Hardening Effects on the Dynamics of structure by using electromagnetic actuator

The effect of an electromagnetic actuator (EMA) with an LCR circuit on the frequency response of a cantilever beam is investigated in this paper using theoretical analysis and numerical simulation. Specifically, the effects of the influent parameters, such as the air gap of EMA and the amplitude and frequency of the LCR circuit, were assessed regarding their modulation effects on the dynamic behaviour of the system. The aim is to optimize the design of the test rig. The theoretical analysis based on the harmonic balance method is used to solve the electromechanical coupled dynamic equations of the system. The results show that the system can introduce a controlled hardening effect in the structure. Furthermore, it can be seen that the hardening characteristic of the system could be controlled with the variation of the excitation voltage amplitude or the proximity of the driving frequency to the resonance frequency of the circuit. The theoretical analyses are in good agreement with the numerical simulation results. The results obtained provide the required elements for the design of the test rig necessary for the experimental validation.