title: Development of a Mobile Toolmark Characterization/Comparison System.
abstract: Since the development of the striagraph, various attempts have been made to enhance forensic investigation through the use of measuring and imaging equipment. This study describes the development of a prototype system employing an easy-to-use software interface designed to provide forensic examiners with the ability to measure topography of a toolmarked surface and then conduct various comparisons using a statistical algorithm. Acquisition of the data is carried out using a portable 3D optical profilometer, and comparison of the resulting data files is made using software named "MANTIS" (Mark and Tool Inspection Suite). The system has been tested on laboratory-produced markings that include fully striated marks (e.g., screwdriver markings), quasistriated markings produced by shear-cut pliers, impression marks left by chisels, rifling marks on bullets, and cut marks produced by knives. Using the system, an examiner has the potential to (i) visually compare two toolmarked surfaces in a manner similar to a comparison microscope and (ii) use the quantitative information embedded within the acquired data to obtain an objective statistical comparison of the data files. This study shows that, based on the results from laboratory samples, the system has great potential for aiding examiners in conducting comparisons of toolmarks.
authors.affiliation: Ames Laboratory, Iowa State University, 2220 Hoover, Ames, IA, 50011.
authors.forename: Scott
authors.initials: S
authors.lastname: Chumbley
authors.affiliation: Ames Laboratory, Iowa State University, 2220 Hoover, Ames, IA, 50011.
authors.forename: Song
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Ames Laboratory, Iowa State University, 2220 Hoover, Ames, IA, 50011.
authors.forename: Max
authors.initials: M
authors.lastname: Morris
authors.affiliation: Ames Laboratory, Iowa State University, 2220 Hoover, Ames, IA, 50011.
authors.forename: Ryan
authors.initials: R
authors.lastname: Spotts
authors.affiliation: Ames Laboratory, Iowa State University, 2220 Hoover, Ames, IA, 50011.
authors.forename: Chad
authors.initials: C
authors.lastname: Macziewski
keywords: forensic science; optical profilometer; portable prototype; quantitative measurements; statistical comparisons; toolmarks