Abstract
In this paper, the relationship between the cutting resistance force and the machine state was investigated regarding the drilling of small diameter holes by analyzing actual experimental data. From these results, the feasibility of controlling the machine state in terms of the position and rotation angle of the cutting edge and estimating the conditions from a control engineering viewpoint were theoretically examined. The mathematical model in this study provided an observable condition in terms of the position and rotation angle of the cutting edge using state observers.
