Modeling machine tool feed servo drives using simulation techniques to predict performance

A method of predicting servo drive performance for a machine tool with backlash or stiction in the machine system or servo plant is described. By using servo simulation techniques, it is possible to construct a very accurate model of the servo drive. It is possible to observe the effect on performance by changing the drive parameters such as load inertia, backlash, stiction (stick-slip), viscous friction, load thrust, current limit, servo loop gains, machine resonance, and acceleration. Assuming the model is correct, the simulation program allows the machine designer to observe the feed drive performance without having the drive available. This simulation procedure makes it possible to anticipate machine design problems affecting servo performance and to correct them before the machine is built