This report describes the development of methods and reference artifacts that facilitate the introduction and quality assurance of three-dimensional (3D) toolmark topography measurement in forensic labs.
The two key research components of this project are 1) the development of prototype physical reference artifacts for key metrological characteristics of 3D surface topography microscopes and 2) providing guidance on how to implement a quality assurance system to monitor and ensure the quality of topography data acquired for firearm and toolmark (FATM) analysis. The 2-year project began with a landscape survey to assess the state-of-the-art of 3D surface topography instruments. Then major commercial vendors were identified that offered instruments capable of being used in FATM analysis. This effort addressed both general-purpose optical surface topography microscopes and systems designed for FATM examination. Next, various documentary standards were reviewed that offer guidance to practitioners on implementing these types of technology. The project then conducted a survey of commercial physical reference artifacts available for performance evaluation, calibration, and quality control of 3D surface topography measurement instruments and methods. The research conducted in this project provides key building blocks for establishing a strong foundation for metrology needed in the effective implementation of 3D optical surface topography methodologies in the FATM forensic discipline. 27 figures and 45 references