||Dynamometer for cutting force measurement in micro milling
||Hansen, Hans Nørgaard (Institut for Produktion og Ledelse, Danmarks Tekniske Universitet, DTU, DK-2800 Kgs. Lyngby, Denmark)
Bissacco, Giuliano (Institut for Produktion og Ledelse, Danmarks Tekniske Universitet, DTU, DK-2800 Kgs. Lyngby, Denmark)
||Technical University of Denmark, DTU, DK-2800 Kgs. Lyngby, Denmark
||Micro milling is an extremely versatile manufacturing process which allows to produce
complex 3 dimensional shapes; its combination with the replication techniques gives great
advantage for the mass production of micro and meso components. The selection of
cutting parameters cannot be based on the available macro experience for problems due
to the limited scalability of the process; thus it should be based on the knowledge of the
cutting forces. At the moment reliable, accurate and cost effective dynamometers are not
This thesis deals with the design and construction of a dynamometer for cutting force
measurements in micro milling operations. The main challenge is the realization of a
measuring instrument characterized by high resonance frequency, high sensitivity, low
noise and interfaced with an acquisition system with high sampling rate.
After a screening of different possibilities the author decided to exploit the characteristics
of a 3 component piezoelectric sensor to develop the dynamometer. The design of
the components, which have to satisfied the mentioned requirements, is here presented.
After the realization of the static calibration of the dynamometer and an investigation
to reduce the noise level affecting the signal, a particular device was developed for the
verification of the response of the of measuring device. A series of cutting experiments
was performed with different end mill and applying a modular approaches to have reliable
data for further comparisons.
The micro milling process was realized with a conventional machine tool equipped
with an attached high speed spindle. Such system required an accurate control of the
axial depth of cut. The attention was focused on the thermal deformation of the machine
tool structure and of the high speed spindle. A computerized program was developed for
the acquisition of the thermal deformations.
Creation date: 2008-02-08
Update date: 2008-02-08