Provide SI-traceable measurements and standards for ballistic and toolmark identification and surface texture and microform calibrations. Enable innovations in forensic science and manufacturing by developing and implementing state of the art optical and contact surface metrology techniques, algorithms and SRMs. Develop a statistical foundation and a practical procedure to estimate error rates for firearm and toolmark evidence identifications in forensic science.
The Forensic Topography and Surface Metrology Project develops measurement methods, reference artifacts, and objective identification criteria to support forensic toolmark and firearm identifications and surface metrology. The research team has developed NIST Standard Reference Material (SRM) sinusoidal roughness specimens and SRM standard bullets and cartridge cases. The team also developed a 2D/3D ballistic signature acquisition system and applied unambiguous surface similarity metrics to improve the accuracy of ballistics identifications in the course of research in support of the 2008 National Academies Report. In 2008, NIST and the Bureau of Alcohol Tobacco, Firearms and Explosives (ATF) initiated the National Ballistics Imaging Comparison, which introduced procedures for using its bullet and cartridge case SRMs for quality control of automated identification systems widely used in crime labs. A significant advancement at NIST is the recent development of an analytical approach, known as the Congruent Matching Cells (CMC) method, to improve further the accuracy of ballistic identifications, and to estimate the error rate for firearm evidence identifications in forensic science. The research team led ISO standard committees in developing and revising ISO standards in surface metrology and Rockwell hardness standardization.
A. Develop the next generation ballistics identification system characterized by high correlation accuracy, high correlation speed and error rate report to support firearms and toolmark identifications in the U.S.
B. Conduct the National Ballistics Imaging Comparison (NBIC) Project to develop a traceability and quality system for ballistics identifications within the National Integrated Ballistics Information Network (NIBIN).
C. Investigated topography measurement instruments to be used for NIST Ballistics Identification System (NBIS).
D.Invented a “Congruent Matching” theory for accurate ballistics identifications.
-Completed three programs using the CMC method for breech face correlations.
-Completed validation tests using topography and optical images to support the CMC method.
E.Developed an error rate procedure, completed initial error rate calculations with breakthrough results.
F.NIST is the only NMI conducting forensic topography measurements. Team members held 22 presentations include invited talks at PTB (Germany) NPL (UK) and European Network of Forensic Science Institutes (ENFSI) Expert Working Group (EWG); received a “Most Outstanding Presentation Award” at California Association of Criminalists (CAC) 2013 Spring Meeting.
G.The NIST Ballistics Identification System (NBIS) provides a model for developing the next generation ballistics identification system.A U.S. manufacturer is developing their next generation systems based on NBIS.A US manufacturer send an email to NIST in September 2013: “We feel, the Error Rate Software based on the (NIST developed) Congruent Matching Cell theory, could revolutionize the science of firearms comparison, and we wanted a license to sell it…”
Major Activity in Surface and Microform Metrology
A. Surface Metrology:
B. Microform Metrology:
C. ISO and ASME standardization works:
The research team led ISO standard committees in developing and revising ISO standards is surface metrology and Rockwell hardness standardization that include:
Vorburger led the development of two ISO working draft standard “ISO WD 25178-600 Geometrical product specifications (GPS) — Surface texture: Areal — Part 600: Metrological characteristics for areal-topography measuring methods” and the “ISO WD 25178-607 Geometrical product specification (GPS) — Surface texture: Areal — Part 607: Nominal characteristics of non-contact (confocal microscopy) instruments.”
Since 1990’s, Song led research and publications and proposed a revision for microform geometrical specification of Rockwell diamond indenters specified inthe old ISO 6508 standard.In March 2004, the new ISO/FDIS 6508-3:2014(E) standard entitled “Metallic materials — Rockwell hardness test — Part 3: Calibration of reference blocks” has made as suggested by NIST to relax the tolerance range for cone flank straightness from “0.5 μm for maximum” to “0.5 μm for average and 0.7 μm for maximum”, that makes it possible to develop NIST SRM Rockwell diamond indenters in conformance with the revised ISO standard to support U.S. manufacturers.
T.B. Renegar led the ASME B46 standard committee to revise the ASME B46-2009 standard entitled “Surface texture—roughness, waviness and lay”.
· Complete the NIST FMC project: designed a scheme for NIST Ballistics Identification System (NBIS); investigated topography measurement instruments to be used for NBIS; Invented a “Congruent Matching” theory for accurate ballistics identifications; completed three programs using the CMC method for breech face correlations; completed validation tests using topography and optical images to support the CMC method.
· Developed an error rate excel program, completed initial error rate calculations with breakthrough results, drafted a report, passed ERB review and submitted to Science.
· Developed two ISO WD 25178 standards in surface metrology, and revised an ISO 6506 standard in Rockwell hardness tests.
3 major journal papers, 3 drafts, 12 presentations.
Lead Organizational Unit:pml
Source of Extramural Funding:
Industry, Markets and Applications: Surface metrology affects the function of a variety of industrial products ranging over roadways, ship hulls and propellers, automobile and aerospace components, microelectronics, and optics.
Customers: U.S. manufacturers, such as, GM, Ford, GE, Army, Navy, Air Force, Boeing, Intel, Cummins, Lockheed, Los Alamos, VEECO, Pratt and Whitney, Hughes… Collaborators include ATF and NIJ (external) Metallurgy and former SED (internal).
Why are they interested?
Related Programs and Projects:
Physical Measurement Laboratory (PML)