Engineering the Semantic Plant

Engineering complex close fitting encapsulated control systems for plants requires the incorporation of a number of data capture and review processes to eliminate the post start up operational risk as early as possible in the project time frame.

While the 'semantic web' continues to take shape with SPARQL and RDP/OWL databases and their definition taking shape in ISO 15926 construction communities, Invensys is building up the core tools, templates, rules bases and workbench processes to take on larger and larger plant designs in collaboration with it's customers.

Reflected Doyle Spirals - F Decomite [Flickr] [ CC ]

The Doyle Spiral as depicted in Reflected Doyle Spirals beautifully traces the packing of ever increasing circle size in sets of interlocking coloured spirals. These sets have aspects of encapsulation, increasing scale, close fitting components and simple recursive rules to define their behaviour. It is my view that engineering highly scalar control and safety systems follows similar structures, and as such, we might keep in mind how best to frame the close fitting data exchanges between different companies and engineering teams in order to make them equally elegant.

Fig  2  A simple timeline showing the impact of the late arrival of new requirements

When a project is conceived, the design starts off as a concept, probably well understood from prior projects, with a small amount of real data.  As the project moves ahead, it gathers information as soon as possible to determine the main shape of the design.  Questions, knowledge, and missing data abound. Where does the control system fit ?  Where does the safety system fit ? What about the instrument lists ? What instruments will be used ? Where is appropriate to make a join to a SCADA datasource ?  What about the timing ? What bridging elements are required ?

The argument for trying to get a handle on managing the increasing volume of requirements, which come into play as construction designs are finalized, is developed on the basis of managing the late breaking new requirements and their consequent scope changes on the IO schedules and overall control and safety design for the plant. [See figure 2]

Invensys Operations Management has to provide consistent workable control and safety designs delivered over a large range of project sizes and time frames. With the interlocking design of operations control and safety shutdown, with different tools in use, Invensys has developed an engineering workbench practice to help capture the components of the design for later re-work and re-use. The key components and storage artifacts in the workbench are:-

Fig 3 Managing the Engineering Artifacts in a General Purpose Workbench

Control and Safety Systems engineering  is required to make beautiful designs better, safer, and easy to implement on larger and larger projects.  Like the increasing packing of circles in a Doyle Spiral for example, you will find the scale and complexity of larger and larger plants requires stronger and more computerized discipline to get the engineering design and construction done on time. Keeping a consistent set of semantics, rules, templates and exchange capability is important to help reduce the gap on even the next big project.

As experience in the delivery of plant systems grows, encapsulated designs start to populate the drawing offices and engineering spaces of all the contractors and automation vendors associated with a project.  Each of these then has to start to use a common language to have their designs 'fit' together correctly.

The Semantic Web had it's initial description in the May 2001 - Scientific American. Therein find an article entitled "The Semantic Web" by Tim Berners-Lee, James Hendra, and Ora Lassilla. The good news since then is, that the ISO 15926 standard has taken the concept of the Semantic Web to heart, and the engineering group have organised to at least have descriptions and the exchange of data within the construction industry a step closer to being actionable by computing machines.  The group FIATECH have a very good site and membership which best describes the state of the art in development of The Semantic Web as it might apply in the process plant construction industries.

Of course one of the important points about web data which might be converted to knowledge, is that the schema's should apply for small, medium, large, and very large plants.

Invensys, although not directly involved in construction, is very involved in the application of control and safety to the plant and is very involved in the careful design to help minimize any operational risk post startup.  To this end, Invensys is working with key customers to help build workbench tools which not only combine Invensys systems product level engineering tools, templates and rules, but also incorporate the key open interchange components of ISO 15926 in this tools as they go forward.

It is still an evolving landscape, The Semantic Web, but it seems sure that with the groundwork done in ISO 15926 there is the beginning of actual usage of the RDF / OWL technologies that overlay the XML schemas in such a way as to benefit the rapid and accurate interchange of data in the construction of large process plant systems.

Now for those of you that would really like to experience the semantic web, you know, like play with the blocks... I recommend you go to the Visual Data Web and play around with the relfinder demo.  In this demo, you will get a good overview of how relationships, objects, and subjects [the RDF triple] are put together.