An Impact Velocity Device Design for Blood Spatter Pattern Generation with Considerations for High-Speed Video Analysis
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[1] Trent University
Trent University
Canadá
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- Localización: Journal of forensic sciences, ISSN-e 1556-4029, ISSN 0022-1198, Vol. 61, Nº. 2, 2016, págs. 501-508
- Idioma: inglés
- Texto completo no disponible (Saber más ...)
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Resumen
A mechanical device that uses gravitational and spring compression forces to create spatter patterns of known impact velocities is presented and discussed. The custom-made device uses either two or four springs (k1= 267.8 N/m, k2= 535.5 N/m) in parallel to create sev- enteen reproducible impact velocities between 2.1 and 4.0 m/s. The impactor is held at several known spring extensions using an electromagnet. Trigger inputs to the high-speed video camera allow the user to control the magnet’ s release while capturing video footage simultaneously. A polycarbonate base is used to allow for simultaneous monitoring of the side and bottom views of the impact event. Twenty-four patterns were created across the impact velocity range and analyzed using HemoSpat. Area of origin estimations fell within an acceptable range (DXav=+- 5.5+- 1.9 cm, DYav =+-.6+- 2.8 cm, DZav=+5.5+- 3.8 cm), supporting distribution analysis for the use in research or bloodstain pattern training. This work provides a framework for those interested in developing a robust impact device.
