A study on calibration of coefficients in end milling forces model

Abstract

This paper presents an improved approach to calibrate the cutting coefficients in an end-milling model. In order to predict end-milling forces, lots of simulative models are established. In order to use them, coefficients in the models, for example, cutting pressure constants etc., must firstly be calibrated experimentally, and simulative precision and applicability of the models are influenced by them. For simplicity, using average forces to calibrate cutting parameters are widely adopted by lots of researchers. However, the existence of an instrument's zero-drift, noise, etc., will have effect on the precision of experimental data, so, it is difficult to directly obtain exact average-cutting forces through experimental data. Aiming at the above problem, the paper investigates milling forces in the frequency domain, discusses the impact of experimental data at different frequencies on cutting force coefficients and the influence of sensitivity of error on experimental data at different frequencies on coefficients is studied. Based on the research, an improved method to calibrate the cutting coefficients is provided. Based on a series of experiments and numerical simulations, the validity of the method is confirmed. At the end of the paper, some useful conclusions are drawn.Notation f t , f r , f a Tangential, axial and radial local cutting force k t , k r , k a Cutting pressure constants c t , c r , c a Tangential, axial and radial local cutting force coefficients p t , p r , p a Tangential, axial and radial local cutting force exponents

Cutting torque and tangential cutting force coefficient identification from spindle motor current

“…They must be experimentally determined from cutting force measurements for a given combination of cutting tool geometry and workpiece material [4].…”

A Study of Efficiency Eccentric Drilling-Milling Chuck

“…a hex wrench one eccentric 6, that additionally tightens a flared sleeve 3 to create a necessary clamping force [13], [14].…”

Cutting force prediction for ball-end mills with non-horizontal and rotational cutting motions

“…(10a) and (10b) need to be calibrated for each cutter-workpiece material pair in order to calculate the ball-end milling forces. Various approaches for calibrating the cutting force coefficients have been proposed in the literature, such as: processing the instantaneous cutting forces rather than the average cutting forces [36], analyzing the experimental force data in the frequency domain [37], separating the cutting forces into nominal and perturbation components [38], using force data generated from a finite element model [39], and considering the negative effect of cutter runout [40].…”