The document summarizes Wessex Archaeology's use of 3D data capture techniques like laser scanning, photogrammetry, and GNSS in heritage contexts. It discusses the toolbox approach of using multiple techniques, provides examples of projects using different methods like laser scanning at Tamworth Castle and Sandsfoot Castle, and photogrammetry at Wakehurst Place. It also discusses practical considerations for each technique and integrating the data in GIS for analysis and visualization.
Capturing & working with 3D data in heritage contexts
1. Wessex Archaeology
Capturing & working with 3D
data in heritage contexts
A view from the coalface
Paul Cripps
•Geomatics Manager, Wessex Archaeology
•Archaeological Computing Research Group, University of Southampton
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
2. Wessex Archaeology
Overview
• Toolbox
– Laser scanners
– GNSS
– Photogrammetry
– Aerial systems
• How?
– How do we use the tools
available?
– Advantages/disadvantages
– Workflows
• Case studies
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
3. Wessex Archaeology
The toolbox approach
• Many tools/techniques now available
• Each have strengths/weaknesses
• Need to apply right tools for the job in hand
• Right people for the job:
– Survey specialists may not fully appreciated needs of
heritage projects
– Heritage specialists may not fully appreciate survey
techniques
– Team effort!
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
4. Wessex Archaeology
Laser Scanning
• Terrestrial Laser Scanners (TLS), Close Range Laser
Scanners, Airborne Laser Scanners (ALS) provide
additional survey/recording tools
– Not universal panacea
– Ideal for capturing large amounts of 3D surface measurements
– Part of an armoury which includes traditional measured drawing,
photogrammetry, (rectified) photography, TST, GPS and laser
scanners
• Complementary not replacement
– Typically used as part of an overall survey methodology
– Typically used in conjunction with other equipment/techniques/
methods
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
5. Wessex Archaeology
Practicalities (TLS)
• Costs of ownership
– Expensive hardware and software
– Hire vs purchase
– Partnerships
• Skills
– Survey design; how to structure a
survey
– Field survey; how to undertake a
survey
– Data processing; how to prepare
& handle the data
– Visualisation, Analysis &
Interpretation; working with &
producing outputs from the data
• Data
– Massive datasets
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
6. Wessex Archaeology
Practicalities (ALS)
• Costs of data
– Relatively inexpensive to
purchase off the shelf
– Expensive to capture new data
• Skills
– Data processing; how to prepare
& handle the data
– Visualisation, Analysis &
Interpretation; working with &
producing outputs from the data
– Using the data as 3D data vs
static imagery
• Data
– Massive datasets
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
7. Wessex Archaeology
Global Navigation Satellite Systems
• Useful in a range of situations
– Topographic survey / RCHME style earthwork survey
– Geolocating other surveys eg TLS
• Rapid setup
– Smartnet; dGPS but without the base station
– Corrections received over mobile network
(GPRS/GSM)
• Easy to use
– Nearly all Wessex Archaeology archaeologists trained
to use Leica Viva systems
– Shared interfaces with TS
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
8. Wessex Archaeology
Photogrammetry
• A very old & respected technique
• Used to great effect on many projects
– eg original English Heritage / IBM 3D model of
Stonehenge
• Costly in terms of manual processing
• Was seen by many as superceded by laser-
scanning
– Wrong! Laser scanning just another tool
• New life thanks to automated systems
– 123D Catch, Bundler
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
9. Wessex Archaeology
Unmanned Aerial Vehicles
• Range of types
– Gyrocopters
– Fixed wing
• Range of payloads
– RGB HD cameras
– Multi-spectral imaging sensors
• Can be used to provide
imagery for photogrammetry
– Wide area, high resolution
topographic survey
– Very cost effective
– 3cm resolution DSM or better
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
10. Wessex Archaeology
Workflows
• New techniques, new workflows
– Traditional/specified approaches may not be best
suited
– Traditional/specified outputs may be not be what is
required
• Clients may not know how to achieve what they
want
– Consultation in advance
– Recommend appropriate techniques to achieve
outcomes
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
11. Wessex Archaeology
Case studies
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
12. Wessex Archaeology
Tamworth Castle
• Original spec for
photogrammetry
– Way too expensive!!
• Existing laser scan dataset
(recycle award…?)
• New photographic survey
– Ground & aerial
• Combined to produce
stone by stone elevation
drawings
• No need for resurvey
– Cost effective
• High quality product
– Prepared to EH Metric
Survey specifications
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
13. Wessex Archaeology
Tamworth Castle
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
14. Wessex Archaeology
Tamworth Castle
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
15. Wessex Archaeology
Sandsfoot Castle
• Requirements:
– topographic survey of interior & immediate environs including earthworks
– Stone by stone elevation drawings as record
– Panoramic photography
• Restricted access: dangerous structure (crumbly castle on cliff edge!)
• TLSCAD+GIS
– Drawn elevations
– DSM & contours
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
16. Wessex Archaeology
Sandsfoot Castle
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
17. Wessex Archaeology
Sandsfoot Castle
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
18. Wessex Archaeology
Wakehurst Place
• National Trust property
• Complex external elevations
• Drawn elevations, floor plans, etc
– Traditional products
• Combination approach
– Direct & Indirect survey techniques
– image based methods (rectified photography, images+scan
data)
• Survey control network
– Closed loop traverse
• Located using GNSS
– OS map a little out…
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
19. Wessex Archaeology
Wakehurst Place
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
20. Wessex Archaeology
Salisbury Plain
• Monitoring of earthworks
– Topographic survey using
TLS
• Restricted access
– Short fieldwork duration
required
– Weeks for GNSS vs days for
TLS
• GIS based analysis
– DSMs
– Derived products; slope
– Models of change
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
21. Wessex Archaeology
South Wales
• 19 airborne LiDAR
datasets
• 40km2
• 133.5 million data
points
• 2 surface models Elevation component Intensity component
– Unfiltered elevation
– Intensity
• Transcription of
features
– NMP style
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
22. Wessex Archaeology
Tree graffiti
• Record and enhance tree graffiti
– Historical WWI and WWII graffiti warped
by tree growth
• Unwrapping & regression
– Challenging!
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
23. Wessex Archaeology
Stonehenge carvings
Left: (top to bottom) stone 3, stone 3 with ‘axes’ highlighted, stone 53 and stone 4
Above: stone 3 lit from below
Right: accessibility shading
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
24. Wessex Archaeology
Integration & Analysis: GIS
• Stonehenge Visitor Centre
• Environmental Impact
Assessment
– Modelled proposed structures &
tree planting
– LiDAR DSM @ 1m resolution
– Analysed potential visual impact
on >500 archaeological sites
– Probablistic viewshed model
– As built + 5,10,15yr models
– Many many viewsheds!
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
25. Wessex Archaeology
Hamdon Hill
• Topographic survey of earthworks
• Hillfort containing quarry
• Combination approach: Laser scanner
+ GPS
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
26. Wessex Archaeology
Tidworth garrison
• Record garrison in
advance of
redevelopment
• Visualisation of
existing buildings
and their context
• Used to target
further recording
works
– Direct Survey
using (TST)
• 0.75 km2 surveyed
• 37 buildings
• 25 billion
measurements
• 18Gb data file
• 10-25mm effective
resolution
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
27. Wessex Archaeology
Amesbury Archer bones
• Morphological
analysis of skull
– Cross-sections
– Measurements
– Profiles
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
28. Wessex Archaeology
Salisbury Plain
• R&D in collaboration with Leica
• Effectiveness as topographic survey tool
where vegetation is present
– Automated vegetation removal
– Manual workflows
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.
29. Wessex Archaeology
Thanks!
• Thanks to:
– English Heritage
– Archaeoptics For more info:
– 3D Laser Mapping www.wessexarch.co.uk/geomatics
– Kubit www.archaeogeomancy.net
– LatimerCAD p.cripps@wessexarch.co.uk
– Environment Agency
– Warner Land Surveys
– Leica
– Tamworth Borough Council
– Weymouth & Portland Borough Council
– National Trust
– Aspire Defence
– Defence Estates
http://www.wessexarch.co.uk/geomatics Computer Applications & Quantitative Methods in Archaeology. Southampton. March 2012.