Case Study - SCISYS
Software Integration Framework
Today “software” is at the heart of many engineering systems and E-ELT will be no exception. A leading UK software systems company, SCISYS, has therefore been helping ESO understand exactly what that might mean.
E-ELT will be operated using the Telescope Control System (TCS) that will be responsible for controlling the telescope subsystems, many of which will be developed by subcontractors located in various parts of Europe. To support this a software integration framework will be necessary.
The challenges for such a framework will be to support the integration of a wide variety of distributed local control systems with the TCS, while at the same time minimising risk for ESO and the suppliers alike. Furthermore, bearing in mind the ever increasing developments in software technology, the framework will have to offer a flexible upgrade path even though the precise requirements for all the subsystems are not known today. Since the TCS is likely to support changes throughout a 30 year operation, this can have real cost implications.
As part of a technology investigation, UK software experts SCISYS were awarded a contract in 2009 to consolidate requirements on the TCS Integration Infrastructure Software Framework, and provide an architectural design. SCISYS were very familiar with such issues, having already implemented a number of space telescope ground control systems for the European Space Agency. Working alongside colleagues from the UK Astronomy Technology Centre, the work was informed by the software standards activities already being performed by SCISYS in their space telescope projects. The study work for E-ELT therefore involved identifying and proposing architectural solutions to provide common functions on top of a Data Distribution Service layer that would be used for messaging and communications within the E-ELT system itself. The SCISYS approach allows all the disparate sub-systems within the E-ELT to communicate and perform common activities in a consistent manner whilst ensuring that the underlying infrastructure can be made in a way that it is scalable and supportable over the lifetime of the telescope.
Common functions identified and explored included:
- Messaging
- Commanding
- Interaction
- Logging
- Alarms
- Errors
- Configuration
As a result of this work, key aspects have now been taken forward as part of ESO’s E-ELT system design. Head of Ground Segment Technology at SCISYS, Roger Thompson remarked “complex software systems for programmes such as E-ELT are operated for decades and often outlive the technologies on which they were built. Using a standards approach from the space industry, we were able to show how telescope monitoring and control services could be made technology independent – protecting against future obsolescence. We were particularly pleased with the close relationship with the domain experts at ATC who offered very valuable insights into the specific requirements for telescope control. We now look forward to the chance of implementing such a system”