Predictive Maintenanece

Bearing Diagnostics

  • 50% of rotating machinery failures related to bearings failure

  • Why are they hard to diagnose? Nonlinearity

  • The objective is to develop an algorithm that can monitor bearings health and generalize it for various operating conditions ( load and speed)

  • Bearings with various conditions and various severities were investigated

  • A comparison with Envelope Analysis, wavelet and FFT was performed

  • 99% accuracy achieved in classifying the bearing fault then determining the fault severity

Publications: CSNDD | JVA | JVC | CSNDD | ND (book) | TN (book)

Gear Diagnostics of Sikorsky Helicopter Engine

  • A project in collaboration with UTRC

  • The objective is to build an algorithm that can identify faults in one of the gear-boxes using noisey vibration signals

  • Configuration: healthy, root crack on 1 tooth, root crack on 5 teeth, missing tooth

  • 6 DOF model was built and various root tooth crack cases were modeled

  • 99% accuracy achieved in identifying the defect in the gear-train

Publications: PHM | JSEA

Crack Detection in Rotating Shaft

  • A project in collaboration with University of Uberlandia, Brazil

  • Two cracks with different severities were introduced using crack propagator

  • Mutual information was used to rank features

  • Only three features were required to distinguish between the faults

  • 100% accuracy was achieved

Publications: IFTOMM (book)

Fault Detection in Electric Motors

  • A project in collaboration with Western Michigan University

  • Detect inter-turn short circuit (ITSC)

  • Early diagnosis is critical (1 second data)

  • ITSC fault causes overheating result in catastrophic failure

  • Noise in sensor reading

  • 100% accuracy was achieved

Electro-hydrulic Servo Actuator Diagnostics

  • 11th order dynamical model of a two-stage servo actuator system

  • Two parametric faults were studied

      • Increased friction between spool and sleeve

      • Degradation of the armature permanent magnet

  • Single and simultaneous faults

  • High noise

Publications: PHM

Modeling and Control of KUKA iiwa 7 R800

  • 7 DOF manipulator

  • This project is divided into three parts: 1) Kinematic and dynamic modeling 2) Trajectory planning 3) Control

  • A sliding controller is used to achieve the desired motion