A new dynamic modeling approach to fixed joint interface in machine tools

The concept of virtual material was presented for the first time when the flexible joint interface may be considered as a virtual material with the same cross area. The virtual material is rigidly connected with two components situated in both sides of flexible joint interface. By adding an element, a complicated assembled part including a joint interface could be equaled as a simple component without any joint interface in order to simplify the complicated problem about flexible joint interface. A series of exact analytical solutions of elastic modulus, shear modulus, Poisson ratio and density were deduced from virtual material by introducing Hertz contact theory and fractal theory. The virtual material model vibration shapes are in excellent agreement with the experimental results.