Clearance-induced vibration responses of mechanical systems: computational and experimental investigations

摘要

A suitable value of clearance in a joint connection is essential for the relative motion necessity of adjacent links. Even if the size of clearance is small, it should be considered at the governing equation of the system. During the mechanism motion, joint clearance is the basis of contact-impact forces between joint parts. In this study, clearance-induced dynamic responses of a spatial mechanism are investigated. Different clearance sizes and driving speeds are performed. For the computational approach, mechanism model is built using the simulation software ADAMS. The actual features of the system such as contact and friction are also considered at the model mechanism. A contact-impact model that comprises the impact function and the energy dissipation during the contact process is also utilized for the computational evaluations. At the experimental stage, clearance-induced vibrations are obtained from the system bearing as a reflection of impulsive forces. Two accelerometer sensors are used for necessary measurements. The results show that the clearance-based impulsive forces have crucial effects on the vibration responses. Clearance is a reason for the non-periodic vibration behaviors. Both the peak frequency and the vibration amplitude are affected from the clearance sizes and driving speeds.