Post on 13-Jul-2015
Forensic Laser ScanningEugene Liscio, P. Eng.
Present and Future
o AI2-3D, Established 2005, Documentation, Analysis and Visualization…
o Professional Engineers Ontario, October 1997
o President of International Association of Forensic & Security Metrology, (IAFSM, www.iafsm.org)
o Adjunct Professor, 3D Forensic Reconstruction Course at the University of Toronto, Mississauga, January 2013
o Research & Validation in “3D Forensics”
o Co-Developer of Clouds2Max plugin for 3ds Max
o FARO Certified Trainer, January 2014
o AI2-3D, Established 2005, Documentation, Analysis and Visualization…
o Professional Engineers Ontario, October 1997
o President of International Association of Forensic & Security Metrology, (IAFSM, www.iafsm.org)
o Adjunct Professor, 3D Forensic Reconstruction Course at the University of Toronto, Mississauga, January 2013
o Research & Validation in “3D Forensics”
o Co-Developer of Clouds2Max plugin for 3ds Max
o FARO Certified Trainer, January 2014
o 3D Forensic Reconstructions
o Documentation Technologies
o Laser Scanner Accuracy Issues
o Multi-Modal Approach & Analysis
o Visualization
o Cases
o Admissibility
Use of computer graphics to accurately represent an
o Object
o Environment
o Process
o Data
o Event.
Big and Small objects
A Reconstruction is based on available physical evidence and can be used for analysis or for substantive purposes.
A Recreation is mostly a demonstrative or “creative” work (although it may be based in part on physical data), it may rely on witness testimony or other non-physical sources of data.
A Reconstruction is based on available physical evidence and can be used for analysis or for substantive purposes.
A Recreation is mostly a demonstrative or “creative” work (although it may be based in part on physical data), it may rely on witness testimony or other non-physical sources of data.
Measurement/DocumentationDefines the equipment, technology and methods of capture
AnalysisIs the study of captured data and how it can be explored to reveal information that would otherwise be obscure
VisualizationPresentation and delivery of the documentation or analysis in a form that is easily understood
Typeso Bullet Trajectorieso Suspect Heighto Bloodstainso Comparison Analysiso 3D Deviation Analysiso Time-distance relationshipso Angular measurementso Field of view
Types
o Plan Drawings/Sketches
o Still Images/Renders
o Animations
o Real-Time Models
o Virtual Tours/Panoramas
o Virtual Environments
o 3D Prints
Photogrammetry
o Uses a digital camera to capture photographs from varying angles and creates a textured 3D model
Handheld Scanners
o Several companies are offering low cost scanners capable of documenting objects the size of a human body or larger
Laser Scanning
o Uses active source of light energy to “bounce” off a surface and return to a receiver where distance is calculated.
3D scanners are not so versatile that they can be used on all types of surfaces and in all conditions. Like any piece of equipment, there are applications for which they may not be well suited.
Dark surfaces absorb light and make it difficult to get a strong reading to the receiver.
http://hirise.lpl.arizona.edu/HiBlog/tag/spectrum/
Partial hits on a surface provide multiple returns that are difficult to discern from one another. The result on edges and sharp corners is noise
Source: http://www.cmlab.csie.ntu.edu.tw/~liubiti/Merge/
Retexture for better or alternate light spectra
Photos are high resolution
Temperature may indicate time of death.
May also indicate other evidence at a crime scene
Use total station as a control to position scans
Use laser scanner on evidence that requires greater detail
Video records over time
Positions and changes are able to be documented accurately
Use photogrammetry in hard to reach areas or in places where higher accuracy is required
Photogrammetry & Laser Scanner
Photogrammetry Examples
Photogrammetry Examples
Photogrammetry Examples
Use to fill in gaps where scanner cannot reach
Handheld & Laser Scanner
New Uses for Handheld Devices
Fill In Gaps
Use to compare changes in point clouds over time
Point Cloud Comparison
Point Cloud Comparison
Point Cloud Comparison
Point Cloud Comparison
Point Cloud Comparison
Visualization
Plan Drawings
3D Renders
Animations
3D Prints
Webshare2Go
Virtual Environments
Cases
Stabbing Reconstruction
Stabbing Reconstruction
Stabbing Reconstruction
Stabbing Reconstruction
Stabbing Reconstruction
Stabbing Reconstruction
Stabbing Reconstruction
Stabbing Reconstruction
Stabbing Reconstruction
Stabbing Reconstruction
http://gulliblestravelsdma.wordpress.com/2014/04/25/put-that-gavel-down/
How are you using the data? o Detailed Analysiso Visualizationo Plan Drawing
Accuracy - Always have reference measurements!
Training and Certification
There are no known cases where laser scanner data has been inadmissible
FARO scanner data has been accepted at trial on many occasions
IAFSM is looking to develop laser scanning guidelines
Scanner data has been used and demonstrated at trial!
State of Indiana vs. David R. Camm, 74C01-1210-MR-000184Spencer Country Circuit Court, Indiana, USAJudge Name: Johnathan DarttSeptember-October 2013Expert Witness: Eugene Liscio
State of Georgia vs Anthony Johnathan Donald, Criminal Case Number: 13903669 – 42Clerk Superior Court – Cobb County Georgia: Rebecca KeatonJudge Name: GrubbsAugust 2014Expert Witness: David Dustin
http://ethicsalarms.com/2011/04/07/the-saga-of-the-racist-juror-and-the-angry-judge-chapter-two-never-mind/
Thank You!
Eugene Liscioeliscio@ai2-3d.com
www.ai2-3d.com