<p> High-speed machining (HSM) concepts were developed in response to productivity,
quality and cost concerns. Significant advancements in controls and machining technologies
have recently come together to enable the wide spread use of HSM on the
plant floor. However, with the advancement of HSM technology, dynamic problems
associated with modern machine-tool structures have not been fully addressed and
are currently limiting performance in some applications. <p> A key aspect in the modelling of HSM processes is capturing the dynamics of
the system during cutting. Machining over a wide range of rotational speeds necessitates
the inclusion of many more higher modes in the system than traditionally
considered. In addition many of the instruments used to assess performance such as
force dynamometers are not designed to measure the cutting forces at high rotational
speeds and hence the specific cutting force values being used are often times not being
estimated properly. </p> <p> Thus the focus of this research is to develop a new procedure for predicting
the specific cutting forces in the end-milling process for high-speed machining. An
improved mechanistic model to predict the specific cutting force using acceleration
data captured from the workpiece fixture was developed. The development of the
new procedure has also lead to an improvement in the extraction technique used to
establish the modal parameters of a machining system. This new extraction technique
was found to be more flexible and easier to use than other available techniques. </p> <p> The new procedure was investigated to test the effect of choosing the number
of modes of the improved modal parameters extraction technique on the estimation
of the specific cutting force. The effect of filtrating the acceleration signal and the
importance of including the run-out of the cutting tool in the model were also investigated. </p> <p> The new procedure was tested on different setups and with different cutting force
models. Experimental validation of the proposed estimation procedure was carried
out, analyzed and compared to the open literature. The new procedure was found to
be more accurate while being easier to implement. </p> / Thesis / Doctor of Philosophy (PhD)
| Identifer | oai:union.ndltd.org:mcmaster.ca/oai:macsphere.mcmaster.ca:11375/19360 |
| Date | 04 1900 |
| Creators | Omar , Omar |
| Contributors | Elbestawi, M. A., Mechanical Engineering |
| Source Sets | McMaster University |
| Language | English |
| Detected Language | English |
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