The techniques used nowadays in a lot of research centers processing lots of sensor data, for instance wind tunnels, are often based on traditional relational databases. In some cases, no databases are used at all. No care is taken to deliver data under real time constraints. This does not have a negative effect in case data is merely stored for analysis after the measurement process has completed, but it can have disastrous effects when the data is needed for control of critical elements in the measurement process itself.
This report discusses a possible solution to real time delivery storage of data. It does not focus on sensor data. Instead, it should be flexible enough to suit any situation in which it is desirable to distribute data under real time constraints. The newly created solution, carrying the name “SQLbusRT”, is based on the blackboard architecture pattern, which will be explained in this report. A comparison is made on how the architecture of the new solution matches with the blackboard architecture. The choice for the blackboard pattern is mainly for its flexibility in the addition and removal of components to and from the system. System components will be able to work on a shared storage. This shared storage is called the blackboard, giving the name to the architecture pattern. A prototype is developed by combining readily available open source products and creating new interfaces. The open source products which are used in this project are MySQL and ORTE. MySQL is a database management system which is known for its high performance and is used on a large scale worldwide. ORTE is an implementation of the RTPS protocol, which serves as a data communication channel over Ethernet, using a publish subscribe mechanism. An explanation of ORTE and the publish subscribe mechanism is given in this report. This report discusses some tests which were executed to predict the performance, reliability and scalability of SQLbusRT in a simple setup. This set of tests can be extended in future research when SQLbusRT matures.
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