Virtual Cybernetic Building Testbed

Objective:

To develop a real-time, distributed cybernetic building emulator called the Virtual Cybernetic Building Testbed (VCBT). The VCBT consists of a variety of simulation models combined with commercial and prototype BACnet controllers that create a hybrid software/hardware environment suitable for testing various integrated control system components for cybernetic buildings. The VCBT provides a way to simulate fault conditions, fires, and other hazardous events. It can be used to reproducibly test commissioning tools, fault detection and diagnostics (FDD) technology, emergency decision support tools, new building integration and control strategies, and building information models. It is a unique resource for conducting research that would be impossible to safely carry out in a real building. An additional objective is to improve the state-of-the-art for building simulation tools by integrating traditionally stand-alone simulation tools.

Problem:

The dynamic interactions of integrated control systems in a cybernetic building are not well understood. Building owners and operators are increasingly demanding integration of historically separate building automation systems in order to reduce operating costs and better manage their facilities. They need standards, performance metrics, and best practice guidelines to achieve their goals. Ideas are emerging about new ways to make use of the information rich environment that cybernetic building systems can offer. Research to advance these ideas to the stage of commercialization depends upon tools that can reliably and reproducibly test and evaluate alternatives. Building automation system manufacturers and service providers need assistance in developing, testing, and certifying new products.

The problem is hard because real buildings cannot be used. In a real building it is necessary to maintain a comfortable and safe environment for the occupants at all times, weather cannot be controlled or reproduced, and hazardous events like fires cannot be introduced and repeated under controlled conditions. There are no simulation tools that can realistically capture all of the necessary details of a complex cybernetic building system.

The solution is to combine the advantages of simulations with real and prototype building automation products in a Cybernetic Building Testbed that can support research needs, assist manufacturers in testing and evaluating the performance of prototype products, and perform interoperability tests with multiple manufacturers’ products.

Approach:

NIST has already built an operational VCBT with assistance and cooperation from industry partners through cooperative research and development agreements. Both the simulation capabilities and the real building automation system components will be expanded to enable realistic emulation of larger and more complex buildings and a greater variety of normal and abnormal operating conditions. New types of building automation systems will be added to the virtual building and the ability to reconfigure the building design and operational details will be improved. The nature of the improvements will be driven by the research objectives of the users of the facility and by the needs of collaborating industry partners. The eventual goal is to have a facility that can emulate a wide variety of commercial buildings in any climate under both normal operating conditions and a wide range of fault or hazardous conditions. It will become a key tool for developing commissioning tools, fault detection tools, decision support tools for emergency responders, enhancements to the BACnet standard, performance metrics for commercial products, and best practice guidelines for building owners and operators.

In FY 08, the VCBT capabilities will be enhanced to include the capability to emulate central plant systems needed to support research on central plant and system level FDD. Improvements will be made to the ZFM-HVAC model in order to emulate fire spreading in large buildings such as schools, apartment buildings, and office buildings. Refinements will continue to be made to improve integration of HVAC, fire detection, lighting, and access control systems in the virtual building.
Emulations runs will be conducted to test commissioning software for variable air volume HVAC systems, system level strategies for fault detection in HVAC systems, and refinements to the sensor driven fire model. Emulation runs will also be conducted to explore methods to provide time critical information to first responders in an emergency, and to investigate the completeness and utility of building information models.

Potential Impact: The impact of the VCBT will be to speed the adoption and use of cybernetic building technology in commercial buildings around the world. Based on a NIST prospective economic impact study (NISTIR 6303), the economic benefit for U.S. office buildings alone will be $1.5 billion. This research will enable the development of a range of new products and product features that automate the proper commissioning of building systems, detect operational faults, and optimize system performance. It will also speed the development and commercialization of a completely new family of products that provide decision support assistance to emergency responders. Finally, it will be used to develop insights and test ideas that will be incorporated into enhanced standards for communication protocols and building information models. The first commercial products for HVAC system fault detection developed using the VCBT are beginning to enter the marketplace.