Date of Award

Summer 2014

Degree Type


Degree Name

Master of Science in Mechanical Engineering (MSME)


Mechanical Engineering

First Advisor

Monika Ivantysynova

Committee Chair

Monika Ivantysynova

Committee Member 1

Andrea Vacca

Committee Member 2

Qingyan Chen


Although robust models of fluid film behavior between the slipper / swashplate lubricating interface in positive displacement machines have been developed, measuring this same fluid film thickness to a highly accurate degree inside a relatively unaltered axial piston unit has never been accomplished until now. A test method was created to close this gap in available data by measuring fluid film thickness between the slipper and swashplate in a 130cc axial piston pump. Precise knowledge of the gap height between the slipper and swashplate at various shaft angle locations during operation provides critical insight into machine behavior. The design, validation, creation, and implementation of this novel measurement method will be discussed in detail. Additionally, sample results from various operating settings taken at steady state conditions will be presented to provide confidence in the design methodology and recorded data. Finally, a preliminary comparison is also presented between test rig results and a precise slipper / swashplate interface prediction model previously developed at the Maha Fluid Power Center.