RSCy2017March 20 – 23, 2017 - Cyprus

GEOSPATIAL DATA AND GEOINFORMATICS TECHNOLOGIES SUPPORTING SMART CITY STRATEGIES –

THE SENECA PROJECTE. Nocerino a, I. Toschi a, F. Remondino a

A. Revolti b, G. Soria b, S. Piffer b

a 3D Optical Metrology (3DOM), Bruno Kessler Foundation (FBK), Trento, Italy

b Trilogis Srl, Trento, Italy

“Smart cities”: future trend

• According to the UN World Urbanization Trend (http://esa.un.org/), in 2050 about66% of the world population will live in urban areas.

• By 2030, the world is projected to have 41 mega-cities with more than 10 millioninhabitants.

• It is clear that a more efficient mapping, understanding and management of theurban ecosystem is required → “Smart City” concept

All these numbers and future trend encourage the rapidly growing sector of

3D GEOSPATIAL DATA AND GEOINFORMATICS TECHNOLOGIES

SUPPORTING SMART CITY STRATEGIES

www.eureka-smart-cities.org

“Smart cities”: 3D City Modelling

The need for a realistic 3D modelling for cities is evident and an increasing spectrum of potential applications urgently demands advanced methods

for efficient and automated urban reconstruction.

3D City Modelling: open issues

The potential of 3D data is mainly confined to visualization purposes, although the geometry and the appearance of 3D building models are just the tip of the iceberg.

Significant manual editing and unrealistic assumptions are still required, although the geometry of historic city centres is far away from the “Manhattan-world”.

Oblique airborne photogrammetry is rapidly maturing, although its potential is still underexploited especially when it comes to the use of oblique views for façade modelling.

The SENECA project

Therefore, the major challenge today is to create automatic procedures that make best use of available technologies and data.

Geospatial data modelling

Geoinformatics technologies development

3DOM = 3D Optical Metrology

Bruno Kessler Foundation

High-tech SME for innovative GIS solutions

Smart and SustaiNablE City from Above

seneca.fbk.eu

The SENECA project

In this framework, the project aims to support the actual exploitation and valorisation of urban 3D reconstruction by developing innovative solutions that

GEOMETRY CAPTURE: 3D POINT CLOUD

GEOMETRY MODELLING: 3D BUILDING MODELS

GEOMETRY ENRICHMENT:3D GEO-DATABASE

MANAGEMENT SYSTEM

(i) efficiently exploit the aerial photogrammetric workflow (aerial triangulation and dense image matching)

(ii) derive topologically and geometrically accurate 3D geo-objects with a multi-scale approach

(ii) link geometries with ancillary information within a scalable and expandable 3D environment

Case studies

The developed methodology is tested on two test sites, that vary in urban characteristics and pose different reconstruction challenges.

Google Earth

Trento (Italy)

Population: 117.000 inhabitantsTest area: 3.5 x 1.5 kmGeography: it lies on the banks of the river Adige, in the homonymous valley. It is surrounded by the Alps.Urban characteristics: it presents older buildings with complex shapes (Romanesque, Medieval and Renaissance style), located in a densely built city centre. The outskirts contains residential and commercial buildings.

Graz (Austria)

Population: 280.000 inhabitantsTest area: 3.0 x 1.5 km

Geography: it is situated on the banks of the river Mur. It lies in a basin, southeast of

the Alps.Urban characteristics: it presents a

medieval main square surrounded by narrow streets, with Renaissance and Baroque architectures. The outskirts

features single houses in a residential area.

Input: spatial data

1. VIS airborne oblique and/or nadir images

UltraCamX Prime (Trento – flown by AVT)

UltraCam Osprey I(Graz – flown by Vexcel)

Nadir Nadir Oblique 45°

Sensor size (mm) 103.86 x 67.86 70 x 45 23.5 x 36 (L/R)

71.5 x 23.5 (F/B)

Focal length (mm) 100.5 51 80

GSD (m) ~0.10 ~0.12(*)

Y/X Overlap (%) 80/60 75/65(*)

# Images Nadir/Oblique 397 20/160

# GCP/CP 14/6 4/3

(*) Computed on nadir images

Source: Vexcel Imaging

Input: spatial data

2. Thermal orthophoto

0.0 km 3.4 km

10

5

0

-5

-10

-15

-20

[C°]

TABI-1800(Graz– flown by AVT)

Date and time20 Dec. 2011

19:38 – 22:02 CET

Processing

• Raw thermal data processed by ITRES Research

• Orthorectification based on LiDAR DSM

Orthophoto spatial resolution [m]

0.60

Source: AVT and ITRES

3. Land cadastre map with building footprints (and land parcel IDs)

Input: non-spatial data

3. Energy Performance Certificates incl. • energy consumptions• carbon dioxide emissions• energy efficiency indexes• etc.

4. Sources of artificial light (single spots)• streetlights• advertising• etc.

5. Data from the register of buildings• owner• number of rooms• surface• property category• etc.

Collaboration with local public

authorities, SMES and private

organizations

Geometry capture: 3D point cloud

Trento Graz

TrentoAT (Nadir images, 6 CPs)

RMSE X [m] 0.08

RMSE Y [m] 0.05

RMSE Z [m] 0.09

GNSS and GCPs observations includedin the BBA as observed unknowns

2.5D DSM CLOUD5.5 billion points,

10 cm spatial resolution

Geometry capture: 3D point cloud

Trento

Geometry capture: 3D point cloud

Graz AT (Nadir and Oblique images, 3 CPs)

RMSE X [m] 0.05

RMSE Y [m] 0.04

RMSE Z [m] 0.02 (0.08 only N)

• The BBA is supported by the calibrated relative orientation parameters

3D POINT CLOUD60 million points

(subset), 10 cm spatial

resolution

• GNSS and GCPs observations included in the BBA as observed unknowns

Geometry capture: 3D point cloud

Graz

Geometry capture: 3D point cloud

Geometry modelling: 3D building models

Trento

Graz

Graz

(*) According to the OGC standard CityGML

(*)

Geometry modelling: 3D building models

Trento At urban scale: LOD1 building models• polyhedral models;• input: Digital Terrain Model and cadastral

footprints;• Footprints are extruded to a uniform average

building height.

At neighbourhood scale: LOD2 building models• models composed by complex roofs and vertical

walls connecting them;• input: DMS cloud, Digital Terrain Model and

cadastral footprints;• segmentation process: the result is a partition of

the points, where all points in one segment belong to the same shape.

• building generation: the detection of building objects is performed by searching for selected types of internal- (or user-) defined roof types.

At building scale: LOD3 building models• architectural models with detailed wall and roof

structures;• input: cadastral footprints and data from the

register of buildings;• building models are generated using CAAD-based tools

Geometry modelling: 3D building models

Graz 10

5

0

-5

-10

-15

-20

[C°]

3D MESHtextured with VIS images

3D MESHtextured with THERMAL ortho

Work in progress:• orthophoto classification;• semantic labelling transfer from 2D to 3D

data;• urban geometric reconstruction

supported by semantic knowledge• semantically-enriched 3D city modelling

BUILDING GRASS TREES STREET

GEOMETRY ENRICHMENT: 3D GEO-DATABASE SYSTEM

Platform architecture

Data access layer:• it provides access to the DB, PostgreSQL with PostGIS, in-house customized • DB stores geometry at different LODs, each building is associated to a unique ID;• queries are performed on spatial data to retrieve ancillary info, and vice versa.

Raw data management layer:• it allows to manipulate raw geo-data and import them in the data access layer.

Business logic layer:• it allows to manage permissions and filters for a proper handle of sensitive and

confidential data.

Service layer:• it manages data exchange with the other layers and provides public APIs for

data import and integration with third-party sw.

Presentation layer:• it is the web application that makes data available to the end-users.• it manages 3D view of geometries, texture projection and render of map layers. • 3D navigation and rendering are performed using the virtual globe Web World

Wind (Nasa), in-house customized.

Multi-scale navigation and queryFrom LOD1 models at urban scale, to LOD2

photo-textured models at neighborhood scale

From LOD2 models, to LOD3architectural models with

associated ancillary information

GEOMETRY ENRICHMENT: 3D GEO-DATABASE SYSTEM

Conclusions and future works

Future works within the SENECA framework will be aimed to:

Extend the platform content

• open data issued by public administrations (harmonisation strongly required);• further environmental pollution sources (e.g. CO2 emission and noise pollution);• direct links to publicly-available DBs.

Further support the “Smart” exploitation of the system

• improvement of the multi-scale rendering performance;• space management in “true” 3D space;• simulations (energy heating demand, PV-suitability of the roofs, noise pollution).

Encourage an active involvement of the public

• from “nice-to-have” to “need-to-have”;• organization of public events to show results and receive feedbacks;• create dialogue among potential users (PA, real estate companies, security

companies, private owners, general public, etc.).

Conclusions and future works

The need for a realistic 3D modelling for cities is evident and an increasing spectrum of potential applications urgently demands advanced methods

for efficient and automated urban reconstruction.

SENECA demonstrated a step forward

towards:

The actual exploitation of 3D data potential:• 3D city modelling is far more then the 3D realistic

visualization of urban environment;• semantic modelling is the future key issue.

The urban reconstruction of complex scenarios:• 3D modelling of historic city centers requires an

improvement of traditional reconstruction methods;• cadastral registration needs to progress to a 3D

approach.

The use of oblique views to support 3D city modelling:• the inclusion of obliques asks for an adjustment of

traditional photogrammetric pipeline;• slanted views can provide detailed info on building facades,

however integration with terrestrial data is still required.

GEOSPATIAL DATA AND GEOINFORMATICS TECHNOLOGIES SUPPORTING SMART CITY STRATEGIES –

THE SENECA PROJECT

Isabella ToschiFBK - Fondazione Bruno Kessler

3DOM – 3D Optical Metrology UnitTrento, Italy

web: http://3dom.fbk.eu email: toschi@fbk.eu

http://seneca.fbk.eu/

RSCy2017March 20 – 23, 2017 - Cyprus