Drawing inspiration from the movements of elephant trunks and octopus tentacles, researchers at the CREATE lab of t. It ishe Swiss Federal Institute of Technology Lausanne (EPFL) has developed a revolutionary robotic structure, the "trimmed helicoid."
Set to usher in greater compliance and control in robotic design, this structure ensures safer interactions between humans and robots and is a result of blending computational modeling with astute biological observations.
The research team, led by Professor Josie Hughes, collaborated with the Department of Cognitive Robotics at TU Delft, and their findings have been published in the prestigious journal npj Robotics.
"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 Professor Hughes in a statement. “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."
A softer approach.
Often hindered by their rigidity, traditional robots are unsuitable for delicate tasks or close human interactions. However, the soft robot arm created by the EPFL team has been meticulously designed to overcome these limitations.
What sets this soft robot arm apart is its remarkable ability to adapt to various shapes and surfaces. This flexibility makes it an ideal tool for intricate tasks such as picking fruits or handling fragile items.
It may become the go-to solution for delicate assembly lines in industrial settings, working alongside humans to enhance their capabilities rather than replace them. Furthermore, the agricultural industry stands to benefit from its gentle touch in crop handling, easing workload during intense harvesting periods.
The researchers creatively modified a spring-like spiral, called a 'helicoid,' by trimming certain sections. This seemingly simple act enabled them to precisely control the spiral's flexibility and stiffness in different directions.
By adjusting its shape, they made the inner part resistant to compression and the outer part flexible enough to bend easily. This unique design resulted in a soft robot capable of movements and actions previously unseen, mirroring the dexterity and soft touch found in an elephant's trunk or an octopus's tentacle.
Professor Hughes reflected on their approach: "By observing these animals and developing a novel architectured structure, we aim to mimic this range of motion and control found in nature."
The team employed advanced computer modeling to translate observations into tangible results. These models facilitated iterative testing of their innovative spiral designs, culminating in the trimmed helicoid shape.
Using computational modeling for designing and optimizing allowed them to assess the geometric structure for maximum workspace and compliance. The result is a robotic creation that draws inspiration from nature but is refined with precise human ingenuity and computer modeling.
"In the end, our computer models were accurate to the point where we only had to build one version of the arm," proudly remarked Professor Hughes.
Shaping the future of robotics.
The achievements at EPFL's CREATE lab signify a paradigm shift in robotics. Traditional robotic applications, often dominated by rigid mechanics, may soon witness a transition towards softer, more human-friendly counterparts. A patent has been filed for this pioneering soft manipulator, and a joint start-up named "Helix Robotics" has been launched, a collaboration between EPFL and TU Delft.
Professor Hughes aptly summarized the significance of this milestone, saying, "Merging keen observations from nature with precise computational modeling has unveiled the potential of soft robotics for future commercial applications. Our aim is to bring robots closer to humans, not just in proximity but in understanding and collaboration.”
“We hope that this soft robotic arm exemplifies a future where machines assist, complement, and understand human needs more deeply than ever before."
Study Abstract
The development and use of architectured structures is changing the means by which we design and fabricate soft robots. These materials utilize their topology and geometry to control physical and mechanical structural properties. We propose an architectured structure based on trimmed helicoids that allows for independent regulation of the bending and axial stiffness which facilitates tuneability of the resulting soft robot properties. Leveraging FEA and computational analysis we select a geometry that provides an optimal trade-off between controllability, sensitivity to errors in control, and compliance. By combining these modular trimmed helicoid structures in conjunction with control methods, we demonstrate a meter-scale soft manipulator that shows control precision, large workspace, and compliant interactions with the environment. These properties enable the robot to perform complex tasks that leverage robot-human and robot-environment interactions such as human feeding and collaborative object manipulation.
Originally published on Interesting Engineering : Original article