Oil debris and viscosity monitoring using optical measurement based on Response Surface Methodology

Abstract

This paper aims at the development of a method for monitoring oil debris as well as oil viscosity, using the optical measurement. An on-line optical oil debris sensor is designed firstly, then a multi-target tracking algorithm based on Gaussian Mixture Model is custom-developed to compute the properties (velocity, diameter) of wear debris in micro-flow channel through images captured by sensor. A mathematical relationship between debris velocity and debris diameter, debris density, oil flow, oil viscosity, oil temperature is statistically established using a three-level-five-factor box behnken design approach based on response surface methodology analysis. Then the analysis of variance is used to confirm the significance of the variables and their interactions. Finally, to validate the mathematical model, an experiment is carried out to compare its performance to that of results obtained using a pin disc test rig. The results demonstrate the measurement error of debris density and oil viscosity is 6.07% and 7.97%, respectively. The proposed approach has excellent suitability to monitor the oil condition.