Research • Research Areas

Although greater than 95% of all computers in use today are embedded computers, people are generally unaware of their presence. Main lines of research today in embedded systems are in validation of performance, enhancing processor architecture to meet real-time requirements, research in real-time operating systems, real-time networked systems, and enhancing security. Research is being conducted on most of these areas at Sabanci University. Most embedded systems are in control of a physical plant, hence they must complete their decisions within a time limit. In some applications such as auomotive brakes, these time limits must never be missed, making the validation and testing of real-time systems an important research area at SU.

The performance of embedded systems differ from general purpose computer systems where the time required to make decisions based on current inputs (latency) is more important than number of operations per second (throughput). Embedded hardware design focuses on such areas as multi-threaded processors and decreasing latency while keeping the operation of the processor deterministic.

Real-time operating systems schedule many tasks on the processor while making sure that none miss their deadlines. Researchers work to discover new algorithms which meet these goals, aided by hardware designers who produce processors according to their specifications.

Modern manufacturing systems are becoming extremely complex. A single but complex computer system to control them is not very practical because the amount of computation required would be too great. Use of several network controlled smaller computers offers an efficient solution. To meet the real-time requirements, however, all of the computers and the network must have time bounds to complete calculations and the data transfers. This area of networked control systems is new and thriving; seen by most researchers as the future of embedded systems. Such systems will also infiltrate our life under such names as ambient intelligence.

Sensitive data should be protected from being monitored and modified by third parties. This can be done using crypto algorithms. However, since the real-time requirements put a bound on the amount of computation we can perform before decisions must be made, sufficiently secure crypto algorithms that do not load the processor must be discovered. Overall, the research on embedded systems is paving the way to a society which uses resources efficiently. It is one of the key research areas that is both challenging and one that has direct applications, and results which are urgently needed.

Advanced Turbine Seals and Leakage Control Systems

Controlling parasitic leakage and secondary flows holds the key to achieve higher power and efficiency in modern gas turbine engines. Sealing and clearance control is a major issue in turbomachinery design and operational life. Interface sealing controls turbomachine leakages, coolant flows, and dynamics. Sealing is the most cost-effective method of enhancing engine performance. These seals are subjected to abrasion, erosion, oxidation, incursive rubs, foreign object damage, and deposits. They are also exposed to extremes in thermal, mechanical, and aerodynamic loadings including positive and negative strain ranges, large case distortions and impact loadings. With proper sealing improvements at critical interfaces dramatic efficiency improvements can be possible. Advanced sealing research at SU focuses on brush and cloth seals. The research include analyses of stiffness and rotor contact loads including frictional effects, seal thermal analysis, hysteresis/hang-up or blow down, bristle stresses, fatigue life, and oil lift analysis for sump seals.

Turbine Blade Reverse Engineering

Turbine blades constitute some of the most challenging components in gas turbine design and fabrication. Research on turbine blade technology at SU has started as reverse engineering of existing gas and steam turbine blades. Activities include CMM, surface modeling, 3-D solid modeling and analysis.

Micro Hydro Turbines

As we near the end of petroleum age, hydro-power receives enthusiastic attention as a clean and renewable power source. Since most of the hydro-power capacity remains untapped in many small streams, micro-hydro turbines hold the key to utilize this distributed energy which freely discharge to sea. Research at SU involves complete system development for micro hydro-power plants, including design and development of the turbine and the power control units.