Hardware and software facilities Computational Mechanics and Reliability Group

The PHM Laboratory at the University of Greenwich consists of National Instrument PXI System and Data Acquisition Modules.

The PXI System (NI PXI-1042Q) includes NI PXI-8110 Embedded Controller, NI PXI-7851R Multifunction R Series Intelligent data acquisition (DAQ) module with a user-programmable FPGA chip (Virtex-5) for onboard processing and various C Series modules for multipurpose testing. The PHM Lab also has facilities to develop, prototype and test microcontroller and sensor based real-time PHM systems.

LabVIEW Software is used to program the FPGA and Embedded Controller. LabVIEW can also be used to develop very advanced Graphical Unser Interface (GUI) which can control the Embedded Controller or FPGA. MPLAB is used to program the PIC microcontroller.

Capabilities

The PXI System and tools allow the group to perform automated tests on the product or system and can be used to collect data from the tests. Available various C Series modules allow the group to integrate and measure different parameters such as voltage, current, resistance, temperature, acceleration, light and strain. The Developed PHM approach can be programmed into FPGA or Embedded Controller using LabVIEW Software for testing and validation. As the FPGA and Embedded Controller of the PXI System can run as standalone systems, developed PHM can be deployed very easily.

LabVIEW MathScript Software module adds math-oriented, textual programming capabilities to the LabVIEW graphical development environment. Hence, developed mathematical models for PHM can be directly imported into the embedded controller or FPGA for testing or deployment.

Applications

PHM for Historical Marine Structure

The PXI System in the PHM Lab was used to measure the corrosion in iron wires with different diameters and under different environmental conditions. Iron wires with different diameters were placed in the desiccator containers with different environmental conditions. The PXI System was programmed to automatically collect resistance measurement at a regular interval for two months. Collected test data was then used for the developed PHM model for historical marine structure.

Real-Time PHM for High Power LEDs

The PXI System was used to test the high power LEDs under accelerated voltage conditions and collect the data. Elevated voltage was applied to the high power LEDs, and voltage, current, temperature and light output were measured and recorded for individual LEDs. These data was then used to develop the real-time PHM approach. The PXI System was also used to program the real-time PHM approach into Embedded Controller and FPGA.

Health and Location Monitoring System for Subsea Power Cable

The developed abrasion wear model for the subsea power cable, based on accelerometer and gyroscope sensors, was performance tested in the LabVIEW FPGA and PIC18F8722. PIC18F8722 was selected for final deployment based on the power consumption, cost, performance and integration. The developed health and location monitoring approach was programmed into the PIC18F8722 and tested for simulated data from the PC and output from the approach was sent back to the PC for visualisation using a GUI.

Combined environmental chamber

  • Size of chamber: 110cm W x 90cm H x 80cm D
  • Thermal shocking and cycling
  • Temperature range: -70°C to +180°C
  • Vibration testing: up to 54grms, 5-5000 Hz
  • Highly accelerated life testing (HALT)
  • High accelerated stress screening (HASS)
  • Environmental stress screening (ESS)
  • Combination of specialist testing as required.

HALT/HAAS testing facility

Our advanced accelerated product reliability testing facility is capable of highly accelerated life testing and stress screening of electronic components. This facility enables discovery of points of failure and the identification of material and design flaws. The facility can be used in conjunction with a multi-axis vibration table.

Multi-axis vibration table

Accelerated life-cycle reliability testing equipment is used to determine points of failure when the PCB, electronic components and solder joints are subjected to vibrations. The equipment can be used in conjunction with the HALT/HAAS testing facility to simulate high temperature, high stress and high vibration environments.

DEK 260 stencil printer

Used in electronics manufacturing for surface-mounted PCB designs, the stencil printer prints solder paste with a high degree of precision onto the PCB. Components are then surface-mounted using the reflow process.

Six zone convection reflow oven

This advanced convection oven for surface-mounted PCB technology lends precise control to the reflow manufacturing process of stencil printed solder paste on the PCB.

X-ray analysis

This facility allows for defect analysis of a PCB and can locate faults that have occurred in electronic products during the manufacturing process, or defects and points of failure that have occurred through environmental factors. The machine can detect a far greater range of production faults than optical inspection alone, including BGA shorts, BGA open circuits and solder quality fluctuations.

Microscopes

To further examine and analyse the inter-metallic composition, manufacturing defects and points of failure of electronic joints and components, an array of scientific microscopes can be employed.

Computational Mechanics and Reliability Group is part of the Faculty of Liberal Arts and Sciences, University of Greenwich.