The Virtual Goniometer: A new method for measuring angles on 3D models of fragmentary bone and lithics
This provides a more efficient and reproducible tool for researchers in archaeology and anthropology, though it is incremental as it improves upon existing measurement methods.
The paper tackles the problem of measuring angles on fragmentary bone and lithics by introducing a virtual goniometer method on 3D models, which is found to be far more consistent and reliable than manual goniometers, with reduced intra-observer variability.
The contact goniometer is a commonly used tool in lithic and zooarchaeological analysis, despite suffering from a number of shortcomings due to the physical interaction between the measuring implement, the object being measured, and the individual taking the measurements. However, lacking a simple and efficient alternative, researchers in a variety of fields continue to use the contact goniometer to this day. In this paper, we present a new goniometric method that we call the virtual goniometer, which takes angle measurements virtually on a 3D model of an object. The virtual goniometer allows for rapid data collection, and for the measurement of many angles that cannot be physically accessed by a manual goniometer. We compare the intra-observer variability of the manual and virtual goniometers, and find that the virtual goniometer is far more consistent and reliable. Furthermore, the virtual goniometer allows for precise replication of angle measurements, even among multiple users, which is important for reproducibility of goniometric-based research. The virtual goniometer is available as a plug-in in the open source mesh processing packages Meshlab and Blender, making it easily accessible to researchers exploring the potential for goniometry to improve archaeological methods and address anthropological questions.