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What is LandXML?The ambition to exchange data throughout a civil engineering/surveying project has long been on the mind of surveying technicians, engineering draftsmen and women and project engineers—often while working with the myriad of file types and software applications and countless versions and patches. These thoughts have been quite often more frustrating than fantasy or wishful thinking.
Enter LandXML. Yet another ‘XML’? No, LandXML is specifically developed and tuned for exchanging design data used in the design/build process for land development and transportation projects. LandXML has evolved from previous efforts and is the cooperative work of representatives from all aspects of our industry.
LandXML offers a standard way for software applications to exchange design and surveying data for the benefit of users in our industry. For end users, frustration is replaced by a few import/export menu clicks; for software application vendors, there is more time to focus on features and new functionality; for government agencies, there is a way to get data delivered in an open, non-proprietary format that can be read and used many years from now.
True data interoperability enables positive workflow changes and improved efficiencies that will ripple through all aspects of our industry. This may indeed be an ambitious aspiration, but given the right technology and open cooperative efforts from members throughout the industry, it is very possible.
The Evolution of a StandardSteve Brown, PE, from the Nebraska Department of Roads, was a key driver of the Engineering and Survey – Exchange, or EAS-E, the predecessor of data exchange to LandXML. Brown did a great job encouraging several U.S. state DOTs (Departments of Transportation) and private software vendors such as Intergraph Corporation (Huntsville, Ala.), Tripod Data Systems (TDS, Corvallis, Ore.), Trimble (Sunnyvale, Calif.), Autodesk Inc. (San Rafael, Calif.) and Bentley Systems Incorporated (Exton, Pa.) to work together to provide a data exchange solution for the entire industry. But in 1999, another ASCII text file standard seemed like a dated solution to a modern problem. The American Association of State Highway and Transportation Officials (AASHTO), a nonprofit, nonpartisan association representing highway and transportation departments in the 50 U.S. states, the District of Columbia and Puerto Rico, and the first organization to test a data exchange solution, declined accepting EAS-E as a standard.
Since XML is the modern form of ASCII text data, it made sense to convert EAS-E into XML and choose a new name for the land development industry, LandXML. LandXML version 0.01 started with a direct translation of the last draft of the EAS-E standard containing ASCII text data, such as COGO points and horizontal alignments. Many revisions and three years later, LandXML version 1.0 is a very comprehensive data model, including raw and reduced surveying data, hydraulics, parcels, surface data and a 3D road model.
In January 2000, the industry consortium LandXML.org was formed from previous EAS-E participants and newly interested parties to total 22 members. Today LandXML.org has more than 200 participants from more than 80 organizations around the world.
Who comprises the LandXML.org industry consortium? Why, you and I; that is, surveyors, technicians, civil engineers, software engineers, professors and government officials from around the world. LandXML.org is an open, no-cost organization that manages the LandXML schema standard, documentation and software development kit.
The LandXML.org industry consortium ratified LandXML version 1.0 as an acceptable standard on July 17, 2002. There are now more than a dozen commercial applications that support LandXML 1.0.
The new open data exchange has evolved to a usable and practical standard through cooperative work of representatives from all aspects of our industry. Experts interested in that type of data defined specific sections of the LandXML schema. For example, a small working group comprised of Trimble, TDS, Leica Geosystems (Norcross, Ga.), GEOPAK (a Bentley affiliate), Autodesk, Bentley and the SDMS (Survey Data Management System) AASHTO task force defined the survey data portion. The roadway model was contributed by the U.S. Federal Highway Administration Office of Geometric Research to ensure LandXML supported the requirement for its Interactive Highway Safety Design Model (IHSDM) project and software.
Another key contributor to the creation of LandXML is Land Information New Zealand (LINZ) and Office of the Surveyor General. LandXML.org began working with LINZ about two years ago to ensure that LandXML could be used as the primary data format for digital lodgment of surveys for an ambitious project call Landonline. LINZ representatives chose to work with LandXML.org to ensure the schema would provide the necessary data for official electronic survey submission, rather than defining its own. The benefit now is the LandXML schema will work for electronic data submittal and LINZ Landonline can be used by any application that supports LandXML 1.0.
What Can You Do With LandXML Today?A visit to www.landxml.org/landxml apps.htm displays a growing number of software applications that support or use LandXML. Typically civil design/ surveying software uses LandXML to exchange COGO points, alignment, parcel and surface data. This is a great start for universal data exchange… but there is more.
It turns out that design data in a LandXML file is also useful for generating all types of reports and for 2D and 3D visualization. Better yet, there are three software applications available that provide customizable report generation using LandXML: Bentley Inroads 8.x, Autodesk LandXML Report Generator and Autodesk Land Desktop 3.
As for 2D and 3D visualization, Autodesk Onsite Desktop 7 will produce 3D renderings of LandXML surface models while providing useful analysis tools.
Also, as of January 2003, surveyors can work with Landonline in New Zealand to extract and submit electronic surveys of record using LandXML data.
The U.S. Federal Highway Administration’s IHSDM program uses LandXML data to provide five different safety and design consistency checks for rural two-lane highway designs. By standardizing on LandXML, the Federal Highway Administration (FHWA) has immediate access to design data from over a dozen design applications that already support the standard.
Another newfound benefit of LandXML is that larger software vendors with multiple products can use LandXML for data migration from current products into new products and are now also able to provide “sideways” data compatibility. “Sideways” data compatibility allows an older and newer application version to shuttle design data back and forth during software upgrade transitions. This provides greater data interoperability across an entire product suite and smoothes the software upgrade process.
What is Next for LandXML?LandXML is a practical data standard designed to solve specific problems and does so in a variety of ways. Work is underway to import design data and then produce raw survey data directly to and from field instruments.
There is ongoing work with U.S. government officials as well as international interest to further extend the usefulness of LandXML. There is also a strong interest in a closer working relationship with other standards efforts such as the International Organization for Standardization (ISO) and the OpenGIS Consortium Inc. to further extend the reach of “open data.”
Of course, if you have any ideas or comments regarding the schema, you are very welcome to join the effort at www.landxml.org/joinnow.htm. The future is open data, and together we share the work and reap the benefits.