1. November 14, 2013 Mechanical Engineering Tribology Laboratory (METL) David Arseneau Research Assistant Sensor Development for a Wind Turbine Bearing Cage

2. 2 November 14, 2013 Mechanical Engineering Tribology Laboratory (METL) Outline Motivation Schematic of a Wireless Strain Telemeter Circuit Diagram Placement of Wireless Strain Telemeter on a Wind Turbine Bearing Cage Future Work

3. 3 November 14, 2013 Mechanical Engineering Tribology Laboratory (METL) Motivation Costs ~$500,000 to replace each bearing in a wind turbine Current wind turbine bearing cage under investigation deforms 74mm

4. 4 November 14, 2013 Mechanical Engineering Tribology Laboratory (METL) Abaqus Results Deformed shape plotted with the undeformed shape Undeformed cage Deformed cage (74mm at max point)

5. 5 November 14, 2013 Mechanical Engineering Tribology Laboratory (METL) Placement of Wireless Strain Telemeters Wireless strain telemeters will be mounted on the bearing cage –Strain gauge in the axial direction –Strain gauge in the tangential direction Printed Circuit Board (PCB) or Kapton will be used to populate the sensor

6. 6 November 14, 2013 Mechanical Engineering Tribology Laboratory (METL) Schematic of Wireless Strain Telemeter Circuit Diagram R2= 1.5kΩ C2= 8.2pF Strain Gauge C=8.2pF R4= 1.5kΩ R5= 1.0kΩ R6= 1.0kΩ R3= 5.0kΩ Antenna Transistors Battery

7. 7 November 14, 2013 Mechanical Engineering Tribology Laboratory (METL) Strain Telemeter on a Wind Turbine Bearing Cage Battery Axial Strain Gauge Circuit components on PCB or Kapton Tangential Strain Gauge

8. 8 November 14, 2013 Mechanical Engineering Tribology Laboratory (METL) Future Work Develop new custom wireless strain telemeter Install on wind turbine bearing cage –Test under static condition –Evaluate in actual wind turbine