Identifying the unit area dynamic characteristic parameters of fixed joint based on equivalent single DOF system

摘要

A whole machine tool structure is a muti-DOF system, it is usually composed of many parts which are connected with joint interfaces. The structure is complicated that the accuracy of modal test is always in a low level. When doing modal test, equivalent single DOF method can not only improve the efficiency and decrease the difficulty, but also exclude interferences such as random noise. In this paper, the author simplified a two-DOF system into an equivalent single DOF system and derived its frequency response function, then analyzed a testing device for fixed joint by using the equivalent single DOF method, and measured several groups of unit area dynamic characteristic parameters of fixed joint interfaces in different materials and different working conditions. The dynamic characteristic parameters can be used in further study of machine tool joint interfaces.