Current Maintenance Regimen

Motivation Predictive Maintenance

ECE 495 VIP Lab:Bearing Telemetry with Temperature Sensitive Paint

Andrew Kovacs, Dimitrios PeroulisSchool of Mechanical Engineering, Purdue University, West Lafayette, IN-47907

Maintenance of military aircraft consumes a large amount of time and resources

• F-16 requires approximately 25 hours of maintenance / hour of flight time

• CH-53 helicopter requires 44 hours of maintenance /hour of flight time

Current methods use preventive maintenance

Normal Bearing

Replacement

Wait for ServiceAppointment

Damage or Failure

Service appointments are scheduled ahead of time based on predicted component lifetime

Smart Bearing

Service

Real-time monitoring and damage detection through the temperature of the bearing cage

Conclusion and Future Work• Setup a real working environment to paint’s usage under dynamic conditions.

• To develop a minimal error calibration curve to correlate intensity ratios to temperatures.

• Seek and develop alternate data analysis and measurement techniques.

• Characterize performance of EuTTA paint under prolonged exposure to heat

Photosensitive AnalysisTeam Members: Steven Streeter & Hersh Lalwani

Light Sensor with High Speed Operational Amplifier1

620nm

1. HAMATSU - Si Photodiode Circuit Examples2. Acroname Robotics – “Connecting a Photoresistor”

Photoresistor Test Circuit2

Photoresistor

TSP Applied to SiliconTeam Members: Brian BellDynamic and Real Environment

Team Members: Michael Green & Arjun Bajaj

Data Acquisition Image

Dynamic Test Rig

Data Acquisition while Bearing is in Rotation

CAGE TEMPERATURE BEST INDICATOR OFINTERNAL BEARING CONDITIONS

If the data image is at a different phase angle the analysis box is at different data points. Investigate

impact and workarounds.

Bearing rotated at 90º

Analysis box

Localized heating in operation

Analysis and Correlation Curve

Chemical Bond Structureof EuTTA

0 20 40 60 80 100 120 1400

0.2

0.4

0.6

0.8

1

1.2 Intensity Ratio Curve

Temperature (C)

Inte

nsity

Rat

io (I

/ I r

ef)

UV light excites the EuTTA which then fluorescence red

light.

The fluorescence intensity varies due to temperature.

T (deg. C)

-150 -100 -50 0 50 100 150

I/Ire

f

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1 23

4

5

67

8

Calibration Curves for various paints.

1.

Sullivan, John and Liu, Tianshu. “Pressure and Temperature Sensitive Paints.” Springer

Bearing

Temperature Sensitive Paint (TSP)

UV Li

Intensity and Long-Term PerformanceTeam Members: Ndu Osonwanne & Mohammed Khan

Surrounding dark box shields from outside light

Bearing is heated to particular temperature and intensity measured

UV LightSource

CCD Capture

Hotplate

48˚C 83˚C30˚C

Light-Proof Box

TSP on Silicon FluorescingUnder UV Light

UV Light and Silicon Setup for Measurements Inside Light-

Proof box

MEMS Cavity Resonator

Electric Current through the Silicon is Detectable Due to the Heating

Future Work: Precisely Monitor Current Flow and Heat Loss on the Silicon

Heating visibly detected using TSP

Test Apparatus