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SA R&D Catalogue » Innovative Design and Manufacturing » UJ
UJ is situated in Johannesburg, Gauteng Province. The Engineering Faculty is constituted of various
departments. The research activities are multi-disciplinary and include Electrical, Electronic and
Mechanical Engineering.
UJ has a well established infrastructure for research on optical fibre sensors and optical fibre
communication and has published extensively in these fields, both at local and international
conferences and in accredited journals over a period of several years. A number of patents have
been registered.
Currently, research is focused also on the application of fibre optics to transducers for various
applications including inertial measurement units for aerospace applications.
| Capabilities/Skills/Expertise |
Transducers based on optical fibre sensors: The measurement of force, moment, pressure,
acceleration, temperature and torque has been achieved, with particular emphasis on the
reduction of electromagnetic interference (EMI) and thermal effects where it is particularly
negative to measurement accuracy or ability. The measurements can be carried out in rotating
or stationary scenarios without the loss of accuracy or introduction of significant noise on the
measured signal (no slip rings or telemetry involved). A large number (100 or more) of different
parameters can be measured and transmitted through a single fibre. The sensors measure strain to
a sensitivity of 1 micro-strain and frequency up to 250 Hz. The application of optical fibre sensors
in wind tunnel balances with improved accuracy, stiff ness and reduced temperature effects has
been studied and demonstrated. Temperature changes can be tracked to 4000oC per second at
temperatures below 200oC. Optical fibre sensors can be imbedded in composite materials and
composite thermo-plastics for use in structural testing, operational testing and health monitoring.
The applications include aerostructures on engines and engine components.
Smart material activators: Developmental research has been conducted in this field for the past
five years particularly aimed at small deflections of small components (MEMS) at high frequencies.
This work can be applied in flight control, excitation of vibration (flutter testing) and active
flutter damping. The actuators can be linear or rotational. Piezoelectric actuation is employed.
The research activities currently also focus on the use of electroactive polymers for actuation.
The sensors/transducers and actuators together offer a wide spectrum of potential applications
in high frequency measuring/control systems for safety, health monitoring and performance in
aeronautics.
Machining of titanium alloys: Light weight metallic materials such as titanium, aluminium
and magnesium are used extensively in the aerospace industry. They are usually subjected to
stringent design and operational requirements, which are usually a function of the manufacturing
process followed. The effect of high performance machining (including high speed machining)
on the surface integrity of certain titanium alloys is currently being investigated. Thermodynamic
and mechanical aspects relating to these high performance machining processes are also being
evaluated. The studies involve experimental testing and numerical modelling of the influence of
various parameters on the machinability of titanium alloys.
Smart composites
Contact person: Professor Japie van Wyk
Tel: +27(0)11 559 2109 / +27(0)11 489 2424
Email: japievw@uj.ac.za
Website: www.uj.ac.za
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