Model Setup IDM Vol 3: Case Studies. Gateway to Melbourne, Australia. Source: Fender Katsalidis, Architects

Transcription

1 Model Setup IDM Vol 3: Case Studies Gateway to Melbourne, Australia. Source: Fender Katsalidis, Architects Version June 2017

2 Contents 1 Case Study Outline The Objective Your Project Context and Team A Representative Survey Document Example 1: 2D Helmert Transformation Example 2: 2D Helmert Transformation Linear Assets - Alignment Appendix 1: National Land Boundary Australia - AU CA CH DE ES FI HU JP NO?? NZ UK US... 4 Appendix 2: Helmert Transformation... 6 Figures Figure 1: Site in the map grid coordinate system (grid north is up the page)... 1 Figure 2: Site in the local grid coordinate system (Y is up the page)... 2 Figure 3: The resultant converted data tested in a Map Figure 4: A New South Wales (NSW), Australia state Cadastral Title document... 4 Figure : Norwegian Jun 2017 buildingsmart Australasia page i

3 Version History Version 0.1 Date May 2017 Scope First draft By JMi May 2017 General amendments JMi June 2017 Revised title Vol 3: Case Studies JMi 7 Jun 2017 buildingsmart Australasia page ii

4 1 Case Study Outline Case Studies 1.1 The Objective In the presentation (BuildingSMART Model Setup-ISG Mar 2107.pdf) you ll see at the end an example of a geo-referenced model. This example is elaborated in detail below. What we are asking case studies to do is to either verify the procedure for an existing project, or undertake the procedure for a new project. In ISG the vendors are starting to implement this (ifcmapconversion etc) subject to some tweaking as outlined in the Mtg 24 notes. The key task is to check the geo-referencing procedure and in your (their) application. Does the vendor need to augment the IFC interface etc or additional attributes displayed for location etc? 1.2 Your Project Context and Team What is the nature of the development, asset type, BIM scope etc. Who are your project team members: Client, Designers, Surveyor, Engineers, Builders etc. and how is the survey/map data used (or could be used). Is this an existing project or a new one? 1.3 A Representative Survey Document In essence can you give an example for your location (Helsinki, Montreal, Tokyo, Madrid )? And if there is an infrastructure example - excellent! What are your national protocols for Land Ownership? In Appendix 2 we are collecting national land boundary methods 1.4 Example 1: 2D Helmert Transformation Based on a similar survey document to that above, in this example two reference points (Ref1 and Ref2) have been defined at opposite ends of the site. The points have been connected to local survey control by a Land Surveyor. The resulting coordinates of the reference points in the national map grid coordinate system (MGA -Map Grid of Australia, Zone 6) are: Ref1 E = 333, N = 6,246, H = Ref2 E = 333, N = 6,246, H = where E is Easting, N is Northing and H is the orthometric height (AHD - Australian Height Datum). All values in metres. Figure 1: Site in the map grid coordinate system (grid north is up the page) 7 Jun 2017 buildingsmart Australasia page 1

5 A local grid coordinate system has been made for the site to reduce the size of the coordinates and to align the site to better fit on paper plans. The resulting coordinates (in metres) of the reference points in the local grid coordinate system are: Ref1 X = Y = Z = Ref2 X = Y = Z = where X, Y, Z represent a right handed Cartesian coordinate system with Z equivalent to up. All values are in metres. Figure 2: Site in the local grid coordinate system (Y is up the page) A Helmert transformation can be computed from the coordinates of the two reference points. The parameters of such a transformation are: X Shift = 333, Y Shift = 6,246, Z Rotation = -7 8'28" Scale = The corresponding ifcmapconversion parameters are: Eastings = 333, Northings = 6,246, OrthogonalHeight = XAxisAbscissa = XAxisOrdinate = Scale = IfcCoordinateReferenceSystem Attribute Name Description GeodeticDatum VerticalDatum Example 1 Map Grid Australia Zone 6 GDA 94 AHD IFC Result #21=IFCCOORDINATEREFERENCESYSTEM('EPSG:2836','Zone 6','GDA94','AHD'); #22=IFCMAPCONVERSION(#nn,#21, ,6,246,77.891,97.47, , , ); 1. Example 2: 2D Helmert Transformation. This example is provided by Andreas Geiger of KHH Forschuungszentrum Karlsruhe. 7 Jun 2017 buildingsmart Australasia page 2

6 The test file AC20-FZK-Haus_GeoRef.zip is available here WNetz?art=Folder.show&id=3281). /* IfcMapConversion */ /* EPSG: ETRS89 / UTM Zone 32N */ /* E */ /* N */ #62= IFCGEOMETRICREPRESENTATIONCONTEXT($,'Model',3, E-,#9,#60); #66= IFCPROJECT('0lY6PUr90TAQnnnI6wtnb',#12,'Projekt-FZK-Haus','Projekt FZK-House create by KHH Forschuungszentrum Karlsruhe',$,$,$,(#62,#374),#49); #100001=IFCCOORDINATEREFERENCESYSTEM('EPSG:2832','UTM Zone 32N','ETRS89',$); #100002=IFCMAPCONVERSION(#62,#100001, , ,113.7, , ,$); Figure 3: The resultant converted data tested in a Map. 2 Linear Assets - Alignment If your project is a linear asset, or has implemented ifcalignment, then add its context, and describe the master GIS setout. 7 Jun 2017 buildingsmart Australasia page 3

7 Case Studies 3 Appendix 1: National Land Boundary 3.1 Australia - AU Figure 4: A New South Wales (NSW), Australia state Cadastral Title document 7 Jun 2017 buildingsmart Australasia page 4

8 3.2 CA 3.3 CH 3.4 DE 3. ES 3.6 FI 3.7 HU 3.8 JP 3.9 NO?? Figure : Norwegian example (tbc) 3.10 NZ 3.11 UK 3.12 US 7 Jun 2017 buildingsmart Australasia page

9 4 Appendix 2: Helmert Transformation The transformation is applied as follows to convert coordinates from local to map grid: where E = (A * X) - (B * Y) + Eastings N = (B * X) + (A * Y) + Northings H = Z + OrthogonalHeight A = Scale * cos(rotation), B = Scale * sin(rotation), and Rotation = atan2(xaxisabscissa, XAxisOrdinate) 7 Jun 2017 buildingsmart Australasia page 6