Current tomography-based devices tend to be bulky and expensive. What’s worse, they can only be used in a safe, customized environment because they use X-rays or ultrasound.
Researchers at Ben-Gurion University of the Negev in Israel have developed a new 3D scanning technique for reconstructing complex objects that is both safe and inexpensive using robotics and water.
The 3D scanning method involves a robotic arm that immerses an object on an axis at various angles and then measures the volume of water displaced by each dip. This sequence is used to create a volumetric shape representation of an object.
"The key feature of our method is that it employs fluid displacements as the shape sensor," said Professor Andrei Scharf, of Ben-Gurion University of the Negev, Department of Computer Science. "Unlike optical sensors, the liquid has no line-of-sight requirements. It penetrates cavities and hidden parts of the object, as well as transparent and glossy materials, thus bypassing all visibility and optical limitations of conventional scanning devices."
Researchers used Archimedes’ theory of fluid displacement — the volume of displaced fluid is equal to the volume of a submerged object — to turn the modeling of surface reconstruction into a volume measurement problem. That served as the foundation for the new method for 3D shape reconstruction.
The research team was able to use the technique on 3D shapes, including an elephant sculpture, a mother and child hugging and a DNA double helix. The results show the dip method was nearly as accurate as the original 3D model.
The new scanning development could have a wide impact on anything from healthcare, to science, to physics or oceanography.
Researchers will present their findings at the upcoming SIGGRAPH conference next week; however, the complete research can be found at the ACM Digital Library.