Modeling and Analysis of the Dynamics of a Drill Penetrating a Thin Plate

Abstract

We propose a simplified model of the drilling process which is useful in understanding the problem of noncircular hole production. The dynamics of a drill penetrating a circular hole in a rigid plate are studied analytically, and numerical methods are then used to include the effects of material removal. We show that certain drill trajectories which lead to noncircular holes can be stabilized by material removal. Based on these findings, we recommend careful drill speed selection as a means of minimizing the probability of noncircular hole production, and explain why even this solution may not be sufficient for the case of very soft or composite plate materials.