On the Nature of Oscillations in the Forces Observed in the Processes of Intermitted Cutting and on the Dynamic Calibration, Green’s Function Method, Direct and Inverse Problems of an Oscillatory System

The theoretical analysis of a single intermittent cutting cycle was carried out to demonstrate that the units of a “lathe–fixture–tool–part” set as an oscillatory system sustain dynamic loads with a corresponding dynamic coefficient. However, the oscillation of the forces measured by a dynamometer does not characterize the change of part–cutter contact (cutting) forces as such. In the case of intermittent cutting, there occur additional loads (additives) to the established cutting force. To determine the perturbing cutting force by the known system oscillation dependence (inverse problem), the Green’s function method and the Volterra first-order integral equation are applied. The kernel of the equation is formed by the dynamic calibration of a dynamometer, and all the information about the oscillatory system is “wired” in it. The efficiency of the method is demonstrated on some examples, and the mentioned additive and dynamic coefficient of cutting forces as such were calculated as a solution for the integral equation.