I have long wondered how we are going to bring building control systems into the wider world. How are we going to use energy models to instrument actual building performance? How are we going to provide the confusing mass of sensors and actuators as surface that is meaningful to Enterprise systems and functions?
I have long favored buildingSmart as a source of the structure and meaning (or semantics as we call them in dweeb-speak). BuildingSmart is the National Building Information Model Standard (NBIMS) rebranded to be more user friendly and international in scope. Building Information Models (BIMs) are data models to track all information about the design, construction, acquisition, and operation of a building. A good BIM starts with the earliest design intents and continues through the final destruction of the building.
I have long known that the fundamental glue of NBIMS is the IDM. Until today, I had no good idea what an IDM was, or how I might go about constructing one for a control system.
It was clear that fitting building controls into BIM would complete many parts of the model while lending coherence to and standard descriptions to control systems. BIM defines energy models during design, models that are not much use during operations. BIM describes assets and provides a framework for defining the interaction between those assets. This sounds quite close to defining the surfaces used in Service Oriented Architecture (SOA).
Today, Dianne Davis, NBIM IDM Technical Chair from AEC InfoSystems was gracious enough to make things clearer for me. IDM stands for Information Delivery Manual. The IDM is a plain English description of the information exchanges needed between two adjacent systems. In buildingSmart, there is an IDM for the exchange between design intents and massing studies, and between massing studies and structural design, and so on.
An IDM for building systems could be added in to the BIM very early on, perhaps right after massing. “I need 3,000 sf of animal quarters which will considered regulated space. The rules for regulated space are that the temperature, humidity, and ventilation be at a defined level, and that information be tracked and reported at an interval not to exceed a certain time. The regulated space requirements for Animal Quarters must meet standard A, while the regulated space requirements for stogie of labile chemicals (such as drug storage) must meet standard B” This approach defines the performance standard required of systems based upon the programmed use of space at a very early stage.
When expressed like this, IDM standards become significant information for energy models. Both standards above, for animal quarters and for drug storage hare similar in that they may have requirements that temperature and humidity be kept in tight, albeit different, ranges. The animal quarters, however, have quite different ventilation requirements, and thereby a different energy cost.
The same IDM defines the performance standards to be tested during commissioning. It should be straightforward to add this IDM information to the COBIE (Common Operations Building Information Exchange) commissioning information. COBIE is that portion of buildingSmart that defines the handover at the end of construction of building information to operations. COBIE also includes a framework for tying commissioning reports to the underlying systems from the design.
It is easy to imagine that an IDM standard for building systems becomes the basis for bidding and construction as well. It is not hard to imagine that IDMs could be defined for each of the 48 types of systems in the original list of vertical markets compiled at the founding of oBIX, whether Intrusion Detection or Medical Gas Distribution.
Who is willing to help me define IDMs for building systems so controls can find a home in the BIM?