3D PRINTING FOR URBAN PLANNING: A PHYSICAL ENHANCEMENT OF SPATIAL PERSPECTIVE Tarun Ghawana Integrated Spatial Analytics Consultants, India Sisi Zlatanova Delft University of Technology, GIS Technology Section, Delft, Netherlands Delft University of Technology Challenge the future • BACKGROUND • 3D PRINTING • COMPARING 3D PRINTING and 3D VISUALIZATION • 3D PRINTING AND GIS • CHALLENGES IN 3D PRINTING OF GIS LAYERS • 3D PRINTING AND CITYGML • CASE STUDY OF DWARKA SUBCITY OF DELHI, INDIA 2 Background • 3D Models are more commonly used now for various planning sectors • 3D visualization enhances spatial aspects in an interacting thematic concerns environment • 3D physical models have been largely used for urban planning for presenting new developments 3 Skepticism • 2007, TUDelft • Wind simulation 4 3D Printing • Additive manufacturing or 3D printing is a process of making 3D solid objects from a digital model. • 3D Printing technique deposits material layer by layer. No waste of material • Numerous 3D printing technologies out there; stereo lithography (SLA), selective laser sintering (SLS) and fuse depositing modelling (FDM) 5 Examples 6 Comparing 3D Printing and 3D Visualization Criteria 3D Digital Visualization texturing, rotating 3D printed models Visual Perception Shading, zooming and Shading, texturing and rotating Scale and Resolution Variation Depending on input data Depending on input data Large Group Discussions Digital display system requirement as inhibitor Detailed enabler Ease to Explore Minimum expertise level required for 3D rendering Easy to handle and explore by inexperienced users Object Selection Single query based multiple object selection Need to tag manually different objects Editing Relatively easier feature editing Limited editing Analyzing Objects Objects analysis requires 3D expertise Objects analysis by non-expert users printed model 7 as 3D Printing and GIS (1/2) • Virtual scenes generated in 3D GIS environment enhance user understanding • Visualization process has passed many stages towards realistic scenes 2D Paper / Other Material Maps (Colour/ B & W) Colour / B & W Scanned 2D Images (noninteractive) GIS 2D Data (Interactive & Attributes Attached) GIS 3D Data (Interactive & Attributes Attached, Virtual Models) Fly-thru 3D Simulation Tours, recorded as motion video Handmade 3D Models of 3D Data (Physical Models) Digital 3D printing of 3D Data with Z properties (Physical Models) 8 3D Printing and GIS (2/2) • single piece objects creation unless impossible by other means of production • possible to print objects within objects, hollow parts, interconnected parts 9 Challenges in 3D Printing of GIS Layers • Translation of various GIS data formats into STL file format • Reducing data loss while translating DEM data into STL file format • 3D printing is not necessarily a cheap process • High level resolution and accuracy of a 3D print but for depending on the size of the model • Work with valid 3D digital models, i.e. closed volume • GIS data varies on compression and projections so it needs to be put back in its original shape 10 3D Printing and CityGML (1/2) • CityGML is currently the only standard for 3D vector data along with semantics, topology and appearance associated with the data Detail Levels Implementation Scale Buildings Details Positional and Height Accuracy Minimum Object Size LOD0 Regional, Landscape Footprint or roof edge polygons LOD1 City, Region Blocks model comprising prismatic buildings with flat roof structures 5 m or less 6x6m LOD2 City Districts, Projects Differentiated roof structures and thematically differentiated boundary surfaces 2 m or less 4x4m LOD3 Architectural Models (Outside), Landmarks Architectural models with detailed wall and roof structures potentially including doors and windows 0.5 m 2x2m LOD4 Architectural Models (Interior) Buildings composed of rooms, interior doors, stairs and furniture 0.2 m or less 11 3D Printing and CITYGML (2/2) • 3D printing characteristics matched with relevant CityGML characteristics (Zprint, Zcorp) Printer Resolution and Minimum Object Type Layer Thickness Size for Printing Build Size for Printing for Printing Vertical Build Minimum Speed for Object Size Printing in CityGML LOD 250 350 650 Resolution: 300 x 450 dpi; Layer Thickness 0.1 mm 0.4 mm Resolution: 300 x 450 dpi; Layer Thickness 0.089- 0.102 mm 0.15 mm Resolution: 600 x 540 dpi; Layer Thickness 0.089- 0.102 mm 0.1 mm (236 x 185 x 127 mm) 20 mm / hour 6x6m 20 mm / hour 4x4m 23 mm/ hour 2x2m (0.236 x 0.185 x 0.127 m) (203 x 254 x 203 mm) (0.203 x 0.254 x 0.203 m) (254 x 381 x 203 mm) (0.254 x 0.381 x 0.203 m) http://www.zcorp.com/en/Products/3D-Printers/spage.aspx 12 Case Study of Dwarka Subcity, Delhi (1/5) • Dwarka sub-city developed recently for approximately 1 million people in Delhi • 29 sectors planned covering around 5,650 hectares • Dwarka landuse distribution follows a distinct hierarchical pattern from sub-city level to sector level Landuse Area (%) Gross Residential 48.54 Commercial 7.05 Government 0.94 Public/Semi-Public 6.20 Recreational 19.94 Transport 14.33 Utilities 3.00 13 Case Study of Dwarka Subcity, Delhi (2/5) • one sample of sector 6 in Dwarka with total area of 93 hectares • Allocated Residential landuse: 41 hectares /410,000 sq. mtrs approx. 14 Case Study of Dwarka Subcity, Delhi (3/5) • Some residential apartment’s society premises are marked on both sides of a road in sector 6 • The covering areas of societies measured as: Maximum: 170 m x 125 m x 40 m Minimum: 80 m x 80 m x 40 m • Disconnected blocks or connected through only a viaduct. • On average, the dimensions of these blocks are around 30 m x 30 m x 40 m in X, Y, Z terms 15 Case Study of Dwarka Subcity, Delhi (4/5) • Single Block Printing Size and Scaling Requirements Single piece maximum printing object size 250 mm x 380 mm x 200 mm Actual Object Size 30 m x 30 m (X,Y) x 40 m (Z) Scale Required 1:120 x 1:78 (X,Y) x 1:200 (Z) • Average scale of 1:160 for the building block, allows printing of a window 2 x 2 m (200 cm/2000 mm) in 12 x 12 mm • 3-4 such building blocks exists in each society, allowing 3D printing in manageable units • Vertical speed of 0.9 inch/hour (23 mm/hour), allows printing a window of 2 x 2 m in a few minutes 16 Case Study of Dwarka Subcity, Delhi (5/5) • Feasible Level of Detail (LOD) as per CityGML, references to 3D print the area of interests on different scales: Area of Interest CityGML: Level of Detail (LOD) Single Block Building (30 m x 30 m x 40 m) LOD 3 With doors and windows A society complex of 3 or 4 building blocks and green / cemented open space in between (100 m x 50 m x 40 m) LOD 3 with doors and windows, trees, open parking spaces and green patches A neighborhood of individual society complexes along a road of 300-500 m in length (300 m x 100 / 150 m x 40 m) LOD 2 with thematically differentiated surfaces and buildings without detailed facades An entire sector of a subcity in 100 hectares LOD1 with blocks model comprising prismatic buildings with flat roof structures 17 Conclusions and Recommendations • Physical enhancement of spatial perspective for the users. • More realistic interfaces for stakeholders negotiations and presenting new development • Detailed 3D model printing possible of landscape, buildings, road furniture etc. for street level planning • Value addition for planners due to the ability to print subsurface utilities, terrain and groundwater variations • 3D printed models can be used in Delhi by various planning agencies • 3D printed model can expedite the negotiations process in city development and planning 18 Thank you for your attention Tarun Ghawana: tarungh@gmail.com 19