Kinder, gentler robotic arm channels its inner elephant and octopus
In order to function safely alongside human workers, robotic arms shouldn't be hard and unyielding. An experimental new arm was designed with that fact in mind, as it mimics soft n' squishy elephant trunks and octopus tentacles.
The prototype device is being developed by scientists at Switzerland's EPFL research institute and the Netherlands' Delft University of Technology (TU Delft).
A series of electric actuators run in a row down its core, linked end-to-end by flexible connectors. Surrounding that core is an open-mesh structure, the polymer elements of which are arranged in a springy spiral (or "helicoid") configuration.
By strategically trimming those elements in different parts of the structure, it was possible to adjust the degree to which it bends and deforms in different directions. In this manner, the team was able to make the arm externally soft and pliable enough to not hurt people it might bump into, yet still firm enough to protect its actuators and other internal electronics from impacts.
The device is also much more flexible than traditional robotic arms that only bend at shoulder, elbow and wrist joints. For this reason, along with its human-friendliness, the scientists believe that the arm would be ideally suited to tasks such as fruit-picking and other agricultural work, caring for the elderly, or assembly line work.
"Through the invention of a new architectured structure, the trimmed helicoid, we've designed a robot arm that excels in control, range of motion, and safety," said the project leader, EPFL's Prof. Josie Hughes. "When the novel architecture is combined with distributed actuation – where multiple actuators are placed throughout a structure or device – this robot arm has a vast range of motion, high precision, and is inherently safe for human interaction."
The arm technology is now being commercialized via spinoff company Helix Robotics. A paper on the research was recently published in the journal NPJ Robotics.