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Steve Brown	Geometric design info exchange Posted: Friday, July 23, 2004 4:52 PM (EST) Exchanging Surface Modeling Data (DTM) through Trans-Xml should not be under estimated: The exchange of Surface Modeling data (DTM) with site design packages, hydraulics design packages and with computer/GPS controlled earth moving equipment is a huge industry gain. I believe that finish paving machines can now the controlled by  computer/GPS technology which means they could also benefit from importing surface model XML data.
Al Butler	Scope of Geometric design schema Posted: Thursday, December 16, 2004 6:10 PM (EST) One continuing issue for recording proposed design and as-built information is its migration to more abstract representations used in GIS databases employed by planning, traffic operations, and maintenance staffs.  For example, inventory staff need to generate point and linear events--perhaps even a completely new section of road--following construction.  While GIS software can read CAD design documents, they do not have the automated capability of taking the detailed set of lines and point symbols and automatically generating the required point and linear events in the agency's database.  There are, however, some successes in identifying useful elements in the CAD drawing that may be utilized for the process; e.g., survey centerline and sign symbols.  For example, one Florida county developed a translation mechanism that allowed Florida DOT-compatible design plans to be moved into a GIS platform by selecting the commonly identified elements.  I would like to see something in the project scope that would at least explore useful options for automating the process of moving design data into highway inventory databases.
Michael Manore	Scope of Geometric design schema Posted: Friday, December 17, 2004 6:10 PM (EST) On behalf of theTRB Visualization Task Force, I would simply like to stress that the project consider the “EVOLVABILITY” of the 2D schema that look to be developed as part of this project.  We understand the funding limits of this project, so only ask that as you make considerations for this need.  As an example, you will be developing: 2D SCHEMA TO DESCRIBE A HORIZONTAL ALIGNMENT 2D SCHEMA TO DESCRIBE A VERTICAL ALIGNMENT Consider how eventually you might effectively combine these into a future 3-Dimensional Trans-XML Schema of a roadway alignment representing it's way through 3D space. Th callenges in sharing 3D and 4D data in the transportation community could be greatly improved, and considerable benefits realize if these data had a more effective standard.  If the team requires further imput on this subject, we would be pleased to provide more specifics. Thank you.
Gary Sanderson	Scope of Geometric design schema Posted: Tuesday, December 21, 2004 11:17 AM (EST) Who knows the building better than the builder?  Who knows the roadway better than the contractor? At the Idaho Transportation Department, we are beginning to get excited about the possibility of creating a database of roadway inventory at the time of construction, rather than our current method of inventorying roadway items by videolog or in the field as requested. I hope we can create a contractor pay item to perform and submit a roadway feature inventory.  We will need some sort of format for this electronic inventory; perhaps this TrnasXML will be useful. Do any of you conduct a roadway feature inventory at the time of construction using an Access-ible database?
Sum Lin	Scope of Geometric design schema Posted: Monday, January 10, 2005 1:36 AM (EST) The TransXML Survey/Design schema will include the elements that form the design model of the roadway. This information may be easily processed into GIS systems and does not have the problem of CAD documents where a significant percentage of the data is not design information but graphics to symbolize, tabulate, label and annotate the design data. The consideration of area features will also allow TransXML to faciliate transfer of relevant GIS information such as environmental areas, soils, wetlands, land use, flood plains, site improvement areas, right of way and cadastral information.
Sum Lin	Scope of Geometric design schema Posted: Monday, January 10, 2005 1:53 AM (EST) Good point.  The current scope of the project is to develop schema for the design control elements, namely the horizontal, vertical, cross sections etc...We need to present information in this fashion since the design controls are experessed in 2D (well us Civil folks work in 3D, but 2D at a time - plan, profile, cross sections).  In most cases, the horizontal and vertical alignments may be “stroke” into a 3D representation for visualization purposes.  Of course, this 3D representation is not useful for any design purposes as the original design parameters will be lost.  This is something I believe most Civil design software packages already do today.  Are you proposing for us to include into the schema a 3D alignment element or something else? There are cases where the horizontal and vertical alignments do not convey adequately the information for 3D visualization.  One example is a special design ditch profile where the profile may be only along a short stretch of the roadway, and is along an uneven edge of the roadway which is not known, yet it it associated with the horizontal alignment for the purpose of stationing.  In this case the true horizontal track of the ditch is undefined even with the horizontal and vertical alignment.  It should be a logical next step for TransXML to include definition of these additional control elements.
Steve Brown	Scope of Geometric design schema Posted: Thursday, January 20, 2005 11:27 AM (EST) I maybe incorrect, but my impression of the geometric design schema scope was summed up in the following statement.  Create a schema capable of containing the necessary geometric design MODEL information necessary to construct a surface transportation project.  This schema could then be feed to intelligent machines or human construction professionals using software to layout the design model.  Please let me know if I am off base. Steve Brown P.E.NDOR
Steve Brown	Scope of Geometric design schema Posted: Thursday, January 20, 2005 11:36 AM (EST) Micheal, Question: are you truly wanting the horizontal and vertical alignments 2D, are you interested in the resulting geometrically correct finished design model 3D.?
George Cassles	Scope of Geometric design schema Posted: Wednesday, January 26, 2005 8:26 AM (EST) It would seem that the 2D design elements must be defined and kept in the schema since the roadway design feeds bridge design. The structures require both the terrain model and the roadway surface design. If TransXML is to provide a basis for the sharing of data by design software then the 2D designs must be provided for and kept. The design elements must be chosen to preserve the design accuracy and usefulness, not because they are useful for geographical queries or  3D pictures.
Sum Lin	Scope of Geometric design schema Posted: Wednesday, January 26, 2005 3:04 PM (EST) George: I agree that it is essential to have schema for design control elements which contain not only the accuracy but also necessary design parameters for the purpose of design revisions or data exchange.
Sum Lin	Scope of Geometric design schema Posted: Wednesday, January 26, 2005 3:10 PM (EST) Steve - When you say "design model" are you referring to a 3d model representing the design surfacce, or are you referring to a "model" of the design elements, composing of alignments, roadway geometrics, cross sections, superelevation etc... that when combined produces snap shots of the model at various critical locations?   Our propsoed scope is limited to the following areas: horizontal alignment, vertical alignment, cross sections, superelevation and roadway geometrics.  We have a limited budget to develop UML schematic models and LandXML schema enhancement recommendations for some of the areas.  Assuming Steve is referring to surface models (design DTMs and breaklines etc...) than the relevant areas will be:   ·  horizontal alignment ·   vertical alignment ·   cross sections ·  superelevation ·  roadway geometrics ·  existing and design surfaces.   We can certain reprioritize this list and work on some areas instead of others.  In my opinion we need to do at least horizontal and vertical alignments, but we may have time to do another one or two areas,  the panel need to decide?
Steve Brown	Scope of Geometric design schema Posted: Thursday, January 27, 2005 9:40 AM (EST) Sum, Actually when I use the term design model, I mean it from the perspective of the consumer of the data or(model).  If the data is consumed by a traditional surveyor for the purpose the construction staking, then the model would consist of horizontal, alignment, vertical alignment,   cross sections, roadway geometrics and existing and design surfaces. Superelevation should be reflected in the cross sections and may not be needed as a separate element. If the consumer of the design model is an intelligent machine, ie GPS controlled scrape or dozer …, then the design model is a DTM surface model representing all the design components mentioned above. The Geometric design schema needs to be able to contain both model definitions.   Hope that helps clarify my statement   Steve Brown NDOR
Sum Lin	Scope of Geometric design schema Posted: Thursday, January 27, 2005 11:27 AM (EST) Steve, That helps.  From that perspective the areas to consider will be horizontal alignment, vertical alignment, cross sections, roadway geometrics and DTM.  A DTM may reflect an existing terrain or a design surface.  It will be up to individual civil products to create a DTM faithfully representing the design control elements (in terms of having the proper break line controls, with sufficient granularity of the data). Regarding superelevation surfaces, our experience has been that cross sections are typically poor represenation of superelevation transitions for a variety of reasons - cross sections taken too far apart, cross section not taken at transition locations, non-linear superelevation transitions make the surface as interpolated from cross sections inadaquate.  I know for example in some of the Bentley products we had to provide tools to create reports or interpolated points from the design superelevation surfaces to feed into paving machines, or to create superelevation transition diagrams to supplement cross section data for that reason.  But for the purpose of TransXML, may be we can leave out superelevation for now with the assumption that the producer of the surface will produce the data in sufficient accuracy to represent superelevation transitions. Given that, we still need to prioritize the areas for investigation: horizontal alignment, vertical alignment, cross sections, roadway geometrics, superelevation and DTM, as given the budget there may not be enough time to invetsigate them all. Regards, Sum
George Cassles	Scope of Geometric design schema Posted: Thursday, January 27, 2005 11:41 AM (EST) The design model described above and the DTM will also be needed if the consumer is a bridge designer. So the elements defined here need to flow through to the other business areas.
Sum Lin	Scope of Geometric design schema Posted: Friday, February 11, 2005 2:04 AM (EST) Seems there is significant interest in including DTM into our analysis.  One possibility is to look at that instead of Superelevation.  We need to finalize our scope for UML modeling in the next day or two so if DTM is important enough to exclude another area please weigh in as your earliest convenience. Thanks, Sum Lin
Carlos Rivera	Scope of Geometric design schema Posted: Tuesday, September 20, 2005 10:17 AM (EST) Tuesday, September 20, 2005 I hope I'm not to late....Superelevation is an important parameter for the the IHSDM (Safety). Where does utility work fall under?  Drainage Structures (Catch basins, pipes, Manholes, etc) & other utilities (underground gas, electric, water, etc) created using Bentley's Inroads Storm & Sanitary.  Bentley currently offers a LandXML translator that is limited to DTM and hor. & vert. alignments.  Will utilities be part of a “feature-based“ DTM model that can be translated to LandXML?
Sum Lin	Scope of Geometric design schema Posted: Wednesday, September 21, 2005 11:33 PM (EST) Carlos: What we posted as a result of our analysis were a series of UML models covering the following areas: Horizontal Alignments, Vertical Alignments, Superelevation, Cross Sections and Plan Featurss. Instead of developing a new schema, semantic models were developed and documented as interpretation and schema change recommendations to LandXML 1.0 and LandXML1.1. You can review the UML models from: http://www.transxml.org/Survey/Group+Documents/Downloads_GetFile.aspx?id=533 One of the difficulties was there are many ways to model the same data in LandXML. This can be a two edge sword. We evaluated the Superelevation element in LandXML and found it limiting.  As a result we proposed a new model to support superelevation data. However, it is my understanding that IHSDM does not use the Superelevation element in LandXML to model superelevation information, but instead they use the Roadway Grade Model element or the Cross Section element for this purpose, so even though we have extended the Superelevation element to the point that it is consistent and   it can model complex superelevation transition data, it will require (1) LandXML.org to accept and adopt our recommendations and (2) IHSDM to take advantage of this new element into their data model. As far as drainage structures, LandXML today has a PipeNetwork element that models structures and pipes. It may be suitable for your needs. We did not cover drainage structures in this part of TransXML studies. As far as DTM, LandXML supports both triangulated or grided surfaces. Even though surface points, edges or faces may be featurized, I do believe non-surface elements like utilities are not part of the surface definitions. Valid LandXML surface definition data are points and faces, and valid LandXML surface source data are points, breaklines, boundaries and contours. I believe the PlanFeature element is intended for non-surface linear features. Sum Lin
Nathan Crews	Scope of Geometric design schema Posted: Tuesday, December 13, 2005 4:19 PM (EST) Sum, I have reviewed the UML model in more detail and comments regarding the LandXML schema. There are many useful comments and suggestions for LandXML-1.1 and future revisions. We will addressing the ambiguity issue by providing new documention with 1.1. The comments on superelevation and the new 3D road model will be proposed for inclusion into LandXML-1.1. Nathan Crews www.landxml.org
Nathan Crews	Scope of Geometric design schema Posted: Wednesday, December 21, 2005 8:19 PM (EST) We just posted 10 new LandXML-1.1 that contain examples of all the new data types in 1.1: Railway cant, 3D Road, design cross sections, curved pipes TIN surface edge visibilty and neighbor optimization, and PI based alignments. http://www.landxml.org/LandXMLSampleFilesDemos.asp Also image files of the samples are provided for most of the files.
Nathan Crews	Scope of Geometric design schema Posted: Thursday, December 29, 2005 10:30 AM (EST) LandXML-1.1 Schema Draft Posted December 23, 2005 Change Detail: http://www.landxml.org/schema/LandXML-1.1/Cumulative%20LandXML-1.1%20Changes.doc Schema Diagram: http://www.landxml.org/schema/LandXML-1.1/documentation/LandXML-1.1Doc.html Updated sample files: http://www.landxml.org/LandXMLSampleFilesDemos.asp Beta LandXML SDK 1.1: http://www.landxml.org/schema/SDK/LandXMLSDK_1.1.zip LandXML SDK 1.1 Highlights: - C++ classes to read and write LandXML files. - Uses the XML DOM parser from the XERCES C parser (version 2.6) from Apache.org. - The entire LandXML-1.1 and LandXML-1.0 schema is supported. - Will read LandXML-0.88, 1.0 and 1.1 files. - Will write LandXML-1.1 files. - Minor porting tasks from 1.0 SDK code. Regards, Nathan Crews www.landxml.org