Credit: ACM SIGGRAPH 2017
Israel research 3D scan water robotics
3-D scanning using Dip Transform. The object is dipped in water (left) using a robot arm, acquiring a dip transform by which the object is reconstructed (right). The team's method produces a complete reconstruction of the complex shape, including its hidden and inner regions.
A group of researchers from Ben-Gurion University in Israel have combined nature with the product of human intelligence to develop a high-accuracy 3D scanning technique.
Bringing together water and robotics, the team believe their method enables the 3D scanning of reconstructing complex objects to be done more accurately than any other existing technique.
The researchers used Archimedes’ theory of fluid displacement, to turn the modelling of surface reconstruction into a volume measurement problem. Here, the volume of displaced fluid is equal to the volume of a submerged object. By adhering to this theory, the researchers have developed ‘a modern, innovative solution for the challenges in current 3D shape reconstruction.
“Using a robotic are to immerse an object on an axis at various angles, and measuring the volume displacement of each dip, we combine each sequence and create a volumetric shape representation of an object,” explains Prof. Andrei Sharf, of Ben-Gurion University of the Negev, Department of Computer Science. “The key feature of our methods is that it employs fluid displacements as the shape sensor. 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.”
The technique is related to an imaging method, called computed tomography, that uses optical systems for accurate scanning. Typically, however, tomography-based devices are bulky, expensive, and can only be used in safe, customised environments. But Prof. Sharf assures their approach is both safe to use and inexpensive.
Prof. Sharf is affiliated with the Advanced Innovation Center for Future Visual Entertainment (AICFVE) in Beijing, China. For this research project, he was joined by Kfir Aberman, Oren Katzir and Daniel Cohen-Or of Tel Aviv University and AICFVE; Baoquan Chen, Qiang Zhou and Zegang Luo of Shandong University; and Chen Greif of The University of British Columbia.
The researchers will present their paper, titled ‘Dip Transform for 3D Shape Reconstruction’, during SIGGRAPH 2017, the world’s largest computer graphics and interactive techniques conference, in Los Angeles next week. It has also been published in the July 2017 issue of ACM Transactions on Graphics.
