DURI: giving robotic arms a "sense of touch" through ultrasound
Imagine the sense of touch, but through a robotic arm. An important milestone, not only for prosthetics applications but for a range of industrial processes where precision and delicacy are critical to a successful outcome. This is the result achieved with DURI – Distributed Ultrasound Robotic Imaging, a patented technology developed by a research group spanning three departments at Politecnico, now working on an advanced prototype.
"Robotic arms fitted with external sensors already exist, but they only provide localized tactile perception at the sensor's exact location," explains Marco Carofiglio, researcher at the Department of Applied Science and Technology-DISAT. "Our work has focused on building a device capable of delivering sensitivity across the entire surface of soft robots." The idea behind the research was to use ultrasound. By integrating a set of sensors and building a distributed network of ultrasound transducers, the team expanded tactile perception from a handful of points to the entire surface of a robot.
The DURI system is currently in the prototyping phase, with expected completion by the end of 2026. During 2027, the research group aims to develop the first demonstrators for industrial applications, while the timeline for transferring the technology to the medical field will necessarily be longer.
The potential applications are numerous. Beyond limb prosthetics, the system could be used in precision processes or procedures where a realistic sense of touch, even if indirect, is essential. Another benefit is monitoring; DURI can track the position in space of a robotic system without relying on traditional visualization systems such as cameras.
Further strength lies in costs. The sensors used are components already widely employed in other sectors, such as mobility, making them easy to source and relatively inexpensive. Only four or five sensors are needed for each robotic arm.
This result was made possible by the highly interdisciplinary make-up of Politecnico's research group, which brings together expertise in physics, materials science, biomedicine, computer science and mechanical engineering. The team, formed in 2024 at the Poli Hack Days – an event designed to spark participants' creativity, ideas and teamwork – is made up of Marco Carofiglio-DISAT, Elena Carlotta Olivetti and Riccardo Gervasi from the Department of Management and Production Engineering-DIGEP, and Fabio Carapellese and Mauro Mancini from the Department of Mechanical and Aerospace Engineering-DIMEAS.
Carofiglio concludes: "We are at a stage in our work were collaborating with companies interested in the robotic arm's applications, but also in its design, would be extremely valuable in moving from the lab to an industrial setting”.