The purpose of this study is to establish a new monitoring technique to detect the state of sliding portion and connecting portion, where it is known that some failure often occurs.
In this paper, we examined the feasibility of estimation for the state in which the support rigidity of the sliding portion using the vibration characteristics in the experiment for a small experimental equipment and in the eigenvalue analysis based on the mathematical model. To simulate the change of the rigidity for the sliding portion, we employ two kinds of material, carbon and molybdenum steel as the ring bush of the ground support. To obtain the natural frequencies and modes for both the case, the impact tests are carried out for several crank angles in the small experimental apparatus as the vibration characteristics is depend upon the crank angle. Based on the obtained natural frequencies, the parameter identification was carried out. As a result, it showed the possibility of estimating the characteristics of the sliding portion by focusing on the natural vibration characteristics.