30 / 05 / 14
Quality criteria for architectural 3D data in usage and preservation processes
Michelle Lindlar (LUH / TIB)Martin Tamke, Morten Myrup Jensen, Henrik Leander Evers (CITA)
QQML 2014Istanbul, May 27th – 30th 2014
30 / 05 / 14
Brief introduction to DURAARK• to 3D scans• to 3D plans (BIM)
Brief introduction todigital preservation
Quality factors• A digital preservation view• A 3D plan / BIM view• A 3D scan view• A stakeholder view
Conclusion and Outlook
Overview
30 / 05 / 14
30 / 05 / 14
DURAARK (DURAble Architectural Knowledge)FP7 – ICT – Digital Preservation (STReP)February 2013 – January 2016
GoalDevelop methods and tools for digital preservationand curation of 3D building data, metadata, related knowledge & web data
Scope• interlinked curation and preservation workflows• focus on two open file formats:
IFC and E57• incorporate existing OAIS compliant
digital preservation system
Project overview
30 / 05 / 14
DURAARK – an interdisciplinary project
30 / 05 / 14
3D building data – scans
ScanCoptor by FaroLabs
Point clouds (E57 – ASTM E2907-11 Standard)
Point clouds are a set of points in a 3D (X, Y, Z) coordinate system which describe the externalsurfaces of a scanned object.
They document a building or structure „as-is“ / „descriptive representations“ and are inevitablytied to temporal and spatial aspects.
Zebedee by CSIRO
http://archive.cyark.org/exterior-cathedral-of-beauvais-3dviewer
30 / 05 / 14
3D building data – models / plans
Building Information Modelling (BIM) (IFC – ISO16739:2013, based on STEP standardsISO 10303)
Moves beyond CAD by covering the entire design-to-construction process (including: project planning, cost, partspecifications, construction time, …). They traditionallydocument a building or structure „as-planned“ / „perscriptiverepresentations“ which may deviate from the as-is state move towards „as-is“ state for facility maintenance.
3D CADGeometry along X-Y-Z axes
4D CADSchedule time
5D CADCost-related information
6D CADEnergy and sustainability
7D CADFacility management
30 / 05 / 14
3D building data – models / plans
30 / 05 / 14
Design-to-Construction-to-Retrofit Model
30 / 05 / 14
Design-to-Construction-to-Retrofit Model
30 / 05 / 14
Why should libraries and archives care ?
3D scans and plans are the research output of respective departments and will be found in future legacy deposits of architects and engineers / current institutional repositories
BIM is already mandatory in several countries for (some) publically funded buildings, including Denmark, Finland, HongKong, Netherlands, Norway,Singapore, UK, USA. Out of those countries all but Hong Kong require IFC for BIM
Cultural heritage organizations are already scanning (and also planning) cultural heritage sitesfor documentation http://archive.cyark.org/exterior-cathedral-of-beauvais-3dviewer
30 / 05 / 14
The 3 [preservation] layers of a digital object
30 / 05 / 14
Digital Object Lifecycle Model
Based on DCC Digital Curation Lifecycle Model
30 / 05 / 14
What does „high quality“ of an object (typically) mean ?
From a digital preservation point of view:To preserve an object at the quality needed to fulfill the future usage scenariosof the stakeholder(s) – i.e., renderability, accessibility, understandability and authenticity of the digital object.
From a user point of view:To use an object in a way that all current needs are fulfilled.
What does ”high quality” mean ?
30 / 05 / 14
Disclosurewell documented and openly available specification, stable versioning
Internal characteristicsfree from encryption and DRM, complexity adequate for intended use
External characteristicsindependent of hardware, physical medium, specific software / OS, external
information
Format acceptancesupport through different vendors / available tools, used by several domains, standardized
Patentfree from patent / licensing costs
Logical Strucuture / TransparencySelf-documented format, standard or simple representation of data at logical structure, transparent to „simple“ tools
Quality criteria for digital preservation:File format sustainability factors
30 / 05 / 14
„Environments“ can be hw, sw, community, institutional/organisationalcharacteristics – such as rendering, editing, storagecost.
Farquhar, Dappert (2009):
„Objects“ includebitstream, representationand intellectual entitylevels – characterisiticscan be page count, resolution, font.
Quality criteria for digital preservation:Significant Characteristics
Characteristics which need to be preserved over the course
of time / over preservation action.Short defintion:
30 / 05 / 14
3D plans / BIM– possible quality descriptors
Level of detail / Level of Development:- indication how much detail is included in geometry / model element
- how much each part of the geometry is developed- e.g. CCS Informationsniveuaer or BIMForum Levelof Development
Level of Accuracy:- indication whether plan (for existing building) isaccurate representation of as-is
- indication scale can reach from „created based onmanual measurements taken from analogue 2D plan“to „created based on 3D scan“
- best practise: DTU (Danmarks Tekniske Universitet)
Level of self-containment:- indiciation of external sources the objectis depending on (e.g., vendor databases) Level of development for plumbing fixtures
taken from BIMForumLevel of Development
30 / 05 / 14
3D scans – possible quality descriptors
30 / 05 / 14
Stakeholder factors
Scanning companies / land surveyors:- high level of detail and accuracy in scans- use detailed parameters to describe deviations (e.g. drift of registration, amount of noise, point to scanner distance, etc.)
Architects and Engineers- focus on lean and uncomplicated collaboration/data to the benefit of the client- level of information should match the purpose
Construction companies- exact and detailed information in plans necessary(highest degree for BIM amongst stakeholders)
Faciliaty maintenance- mid-level of detail required (to lesserdegree than construction companies)
- high focus on correct models(long-term sustainability)
30 / 05 / 14
Conclusion and outlook
Findings- first quality factors which can serve as significant characteristics have been identified- quality expectations differ greatly between thestakeholder groups for architectural data- long-term archives need processes to assess thequality for the respective stakeholders- first tool for E57 quality assessment has beendeveloped in DURAARK project
Outlook- development of IFC quality assessment toolis currently underway- workshops to test tools and processes withstakeholders will take place in the fall
Interested in further information?Deliverables are available on the websitewww.duraark.eu
21 / 10 / 13
Thank you. Questions? Suggestions?
Do you have architectural3D data? Contact us!
