<p>The overall focus of this thesis is the implementation of a process monitoring
system in a real manufacturing environment that utilizes multivariate analysis techniques
to assess the state of the process. The process in question was the medium-high volume
manufacturing of discrete aluminum parts using relatively simple machining processes
involving the use of two tools. This work can be broken down into three main sections.</p><p>The first section involved the modeling of temperatures and thermal expansion
measurements for real-time thermal error compensation. Thermal expansion of the Z-axis
was measured indirectly through measurement of the two quality parameters related
to this axis with a custom gage that was designed for this part. A compensation strategy
is proposed which is able to hold the variation of the parts to ±0.02mm, where the
tolerance is ±0.05mm.</p><p>The second section involved the modeling of the process data from the parts that
included vibration, current, and temperature signals from the machine. The modeling of
the process data using Principal Component Analysis (PCA), while unsuccessful in
detecting minor simulated process faults, was successful in detecting a miss-loaded part
during regular production. Simple control charts using Hotelling's T^2 statistic and
Squared Prediction Error are illustrated. The modeling of quality data from the process
data of good parts using Projection to Latent Structures by Partial Least Squares (PLS)
data did not provide very accurate fits to the data; however, all of the predictions are
within the tolerance specifications.</p><p>The final section discusses the implementation of a process monitoring system
in both manual and automatic production environments. A method for the integration
and storage of process data with Mitutoyo software MCOSMOS and MeasurLink® is
described. All of the codes to perform multivariate analysis and process monitoring were
written using Matlab.</p> / Thesis / Master of Applied Science (MASc)
| Identifer | oai:union.ndltd.org:mcmaster.ca/oai:macsphere.mcmaster.ca:11375/21848 |
| Date | 09 1900 |
| Creators | Wallace, Darryl |
| Contributors | Veldhuis, S. C., Mechanical Engineering |
| Source Sets | McMaster University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis |
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