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|buildingSMART alliance COBieLite: A lightweight XML format for COBie data|
COBieLite: A lightweight XML format for COBie data
by Chris Bogen, PhD and Bill East, PhD, PE, F.ASCE
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The National Building Information Model (BIM) Standard - United States™ is a standard comprised of several different types of content. One of these content types is an "information exchange" standard. Information exchange standards are non-proprietary specifications for the delivery of building information. Such specifications have the potential to integrate information found in typical contract deliverables used.
One of the most widely used NBIMS-US information exchange standards is the Construction-Operations Building information exchange (COBie). The purpose of COBie is to identify and exchange information regarding managed facility assets, starting at the planning of a project, and continuing through the entire project life-cycle. During this life-cycle, the most obvious application of COBie is as a replacement to the current paper-based construction handover documents.
Many of the parties that create information that feeds COBie perform their work using business processes and software that does not require the full weight of building information found in a complete construction handover dataset. As a result a sub-specification of COBie is required to enable such software to deliver just that needed portion of information without the overhead of the entire COBie or BIM framework. The Life-Cycle information exchange (LCie) project demonstrates where, through the entire life-cycle of a generic project, COBie information is created. Central to understanding COBie, and as defined in LCie, is understanding that most exchanges of COBie information do not require the entire set of COBie data found at the construction handover.
COBie files are formatted to support two distinct types of work flows. The first work flow is the exchange of COBie information by software systems that could produce and consume COBie data in its underlying standard format, the Industry Foundation Class Model. The second work flow is one which would have the widest possible visibility to practitioners in the planning, design, construction, and operations fields. This second format, a spreadsheet format, has also been widely adopted in software focusing on the needs of builders and operators.
A new workflow for COBie data has emerged since publication of the two original COBie formats, STEP Physical File Format (i.e. IFC) and COBie Spreadsheet, in 2007. Since 2007 there has been a revolution in information technology related to hand-held and remote sensing devices. These innovative devices do not need access to an entire set of COBie data, but need only to interact with one of the small parts of the data set for purposes that may have nothing directly to do with the delivery of the construction handover data set. Furthermore, spreadsheet XML COBie files contain non-relevant information such as text style, row height, column width that is only meaningful to spreadsheet applications. As a result, there is a need for a more generic specification for the exchange of COBie information between software applications.
COBieLite is designed as a National Information Exchange Model (NIEM) compliant XML specification for COBie that simplifies the delivery and use of facility asset information for application programmers outside the typical architects, engineers, builders, and managers who already use COBie in IFC or SpreadsheetML formats. In short, the COBieLite XML Schema is for programmers what the COBie spreadsheet format is for architects, engineers, builders, and managers.
The "Lite" term is included in the name of this new COBie XML deliverable format because its underlying schema is:
At its core, COBieLite is a NIEM-conformant XML document schema, and it is supported by an integrated development, documentation, and testing tool freely available through Creative Commons License from the OASIS Content Assembly Mechanism (CAM) project. Additionally, COBieLite is supported by numerous other applications and programming libraries that process XML schemas, e.g., Microsoft Visual Studio, Altova XML, SAXON XML Parser, and Apache XML Beans for Java.
COBieLite is mapped to and from both the Facility Management Handover Model View Definition specification of the Industry Foundation Class Model (for IFC 2x3 and 2x4) and the COBie SpreadsheetML format (2.4) as a result COBie is simply another format in which the NBIMS-US standard COBie data maybe delivered.
COBieLite import, export, and checking tools will also be provided as an option in the open source bimServer.org to demonstrate the use of lightweight XML packets in the context of the LCie project. A COBieLite Export is already available in the free COBie Toolkit.
Software vendors may also wish to use the tools freely provided through the OASIS Content Assembly Mechanism (CAM) project to validate import and export of COBieLite files.
The artifacts presented in this page are designated as Release Candidate Four, and future releases will be provided through updates to this page. The Version will be promoted from "Release Candidate" after the publication of the US National Building Information Modeling Standard (NBIMS) v03 where COBieLite appears in the COBie 2.4 ballot.
You may download a .zip of all COBieLite RC2 resources (COBieLiteRC2 All Resources)or download individual components listed below:
The following COBieLite materials, provided in advance of the official release, are for evaluation and planning purposes only.
COBieLite RC4 XML Document Examples With Errors (ZIP) – These error examples were generated by CAM and are provided to provide examples for testing and validation.
Business rules for COBieLite are implemented at the specific LCie exchange specification level. The dictionary for COBie and all Product Type related LCie business rules is included in the XML Schema Resources file listed below. Since there are could potentially be hundreds of example create, read, update and delete transactions, a limited set of examples on one LCie data exchange (Product Installation Report) are provided.
LCie Example: Product Installation Report XML Document Examples (With Errors) (ZIP) – These error examples were generated by CAM and are provided to provide examples for testing and validation.
Common BIM File Examples
Release Candidate 4:
Release Candidate 3:
Release Candidate 2:
Release Candidate 1:
All specifications, documentation, examples, and ancillary materials provided here by buildingSMART alliance are licensed under a Creative Commons Attribution-NoDerivs 3.0 Unported License.