The authors explored two methods in this study: digital photogrammetry, where researchers strategically photograph an object in order to derive measurements; and optical laser scanning, where light is used to measure the object’s physical properties. To begin, the authors filled trays with mixtures of sand, cement, and plaster and instructed a participant to walk through these samples. Four wooden 1 cm cubes were then placed beside a select number of footprints and photographs were taken. A laser scanner was then used to measure the same footprints. This simple procedure was also replicated outside of the lab, at a beach in North West England.
Story: Souri Somphanith, PLOS | Photo: PLOS