Study on Influence of Movable Mass on Natural Frequencies of Cantilever Beam

Frequencies of movable mass and cantilever beam is investigated by combining finite element (FE) analysis with experiment. Free vibration equations are formulated by using discrete method of FE for the coupling system of movable mass and cantilever beam. Three models are built by treating movable mass as concentrated mass, distributed mass, and sprung mass, respectively. Influence of location of movable mass on frequencies of the coupling system is examined by means of numerical computation. Modal experiment system for movable mass and cantilever beam is designed and manufactured. The impact excitation method is employed to measure the modal property of the coupling system with consideration of different status. The comparison of tested data with calculated results is analyzed, and accuracy of three models is estimated. Finally, the influence rule of movable mass on frequencies of cantilever beam is obtained by theoretical analysis and experiment.